Kembriya portlashi - Cambrian explosion - Wikipedia

Buni chalkashtirib yubormaslik kerak Kambriyen kollieri.
Serialning bir qismi
The Kembriya portlashi
Kembriyadagi portlash vazifalari logotipi logo.svg

The Kembriya portlashi yoki Kembriya radiatsiyasi[1] taxminan voqea bo'ldi 541 million yil oldin ichida Kembriy davri deyarli barcha asosiy hayvonlar bo'lganda fitna fotoalbomlarda paydo bo'lishni boshladi.[2][3] Taxminan 13gacha davom etdi[4][5][6] – 25[7][8] million yil va natijada kelishmovchilik eng zamonaviy metazoan fitna.[9] Tadbir boshqa organizmlarning katta diversifikatsiyasi bilan birga o'tdi.[a]

Kembriya portlashidan oldin,[b] aksariyat organizmlar oddiy, alohida hujayralardan yoki mayda ko'p hujayrali organizmlardan tashkil topgan bo'lib, ular vaqti-vaqti bilan birlashtirilgan koloniyalar. Keyinchalik diversifikatsiya tezligi tezlashganda, hayotning xilma-xilligi bugungi kunga o'xshay boshladi.[11] Ushbu davrda deyarli barcha mavjud bo'lgan hayvon phyla paydo bo'ldi.[12][13]

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Minerallashgan birinchi artropodlar karapas (Trilobitlar )
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Birinchidan Cloudina & Namakalat naychali mineral qoldiqlar
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Mollyuska o'xshash Kimberella va uning izlari qoldiqlari
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Arxeonassa- izlarning qoldiqlari

Tarixi va ahamiyati

Asosiy maqola: Hayotning evolyutsion tarixi

"Ibtidoiy qatlamlar" da toshqinlarning tez ko'rinadigan ko'rinishi qayd etilgan Uilyam Baklend 1840-yillarda,[14] va uning 1859 yilgi kitobida Turlarning kelib chiqishi to'g'risida, Charlz Darvin avvalgi qoldiqlarning o'sha paytdagi tushunarsiz etishmasligini uning asta-sekin o'zgarishi bilan kelib chiqish nazariyasining asosiy qiyinchiliklaridan biri sifatida muhokama qildi. tabiiy selektsiya.[15] Kambriyenning paydo bo'lishi haqidagi uzoq vaqtdan beri jumboq fauna aftidan, to'satdan, kashshofsiz uchta asosiy nuqtaga asoslanadi: haqiqatan ham erta Kembriy davrida nisbatan qisqa vaqt ichida murakkab organizmlarning ommaviy diversifikatsiyasi bo'lganmi; bunday tez o'zgarishga nima sabab bo'lishi mumkin; va bu hayvonlar hayotining kelib chiqishi haqida nimani anglatishini. Tafsir etish cheklangan dalillar bilan ta'minlanganligi sababli, asosan to'liq bo'lmagan qazilma yozuvlari va Kembriy jinslarida qolgan kimyoviy imzolarga asoslangan.

Birinchi topilgan kembriy qoldiqlari trilobitlar tomonidan tasvirlangan Edvard Lxuyd, kuratori Oksford muzeyi, 1698 yilda.[16] Ularning evolyutsion ahamiyati noma'lum bo'lsa-da, keksa yoshlariga qarab Uilyam Baklend (1784–1856) toshbaqa toshlaridagi qadam bosimi keskin o'zgarishi biz hozirda kembriy deb ataydigan joy atrofida sodir bo'lganligini tushundi.[14] Kabi XIX asr geologlari Adam Sedgvik va Roderik Merchison fotoalbomlardan tosh qatlamlari bilan tanishish uchun, xususan Kembriy va Siluriya davrlar.[17] 1859 yilga kelib, etakchi geologlar, shu jumladan Roderik Murchison, eng past Silur qatlami deb ataladigan narsa Yerdagi hayotning kelib chiqishini ko'rsatganiga amin bo'lishdi, boshqalari, shu jumladan Charlz Layl, farq qildi. Yilda Turlarning kelib chiqishi to'g'risida, Charlz Darvin trilobitlarning yolg'iz guruhining to'satdan paydo bo'lishini, ilgari ko'rinmaydigan va boshqa qoldiqlarning yo'qligini "shubhasiz eng jiddiy tabiat" deb hisoblagan, bu uning tabiiy tanlanish nazariyasidagi qiyinchiliklar orasida. U avvalgi dengizlar tirik jonzotlar bilan to'lib toshgan, ammo ularning qoldiqlari fotoalbomlar nomukammalligi tufayli topilmagan deb o'ylardi.[15] Kitobining oltinchi nashrida u o'zining muammosini quyidagicha ta'kidladi:[18]

Kambriyen tuzumidan oldingi bu taxmin qilingan dastlabki davrlarga tegishli bo'lgan nega biz qazib olinadigan boy konlarni topa olmayapmiz degan savolga men qoniqarli javob berolmayman.

Amerikalik paleontolog Charlz Uolkott, kim o'qigan Burgess slanets faunasi, "Lipalian" vaqt oralig'i, fotoalbomlarda mavjud emasligini yoki qoldiqlarni saqlamaganligini va bu davrda Kembriya hayvonlarining ajdodlari evolyutsiyasini taklif qildi.[19]

Oldingi qazilma dalillar keyinchalik topilgan. Dastlabki da'vo shundaki, er yuzidagi hayot tarixi orqaga qaytadi 3,850 million yil:[20] O'sha yoshdagi toshlar Warrawoona, Avstraliya, qoldiqlarni o'z ichiga olganligi da'vo qilingan stromatolitlar koloniyalari tomonidan hosil qilingan pog'onali ustunlar mikroorganizmlar. Qoldiqlar (Gripaniya ) ancha murakkab ökaryotik barcha hayvonlar, o'simliklar va zamburug'lar qurilgan hujayralar toshlardan topilgan 1,400 million yil oldin, yilda Xitoy va Montana. Tanishuv jinslar 580 dan 543 gacha million yil oldin ning qoldiqlarini o'z ichiga oladi Ediakara biota, juda katta miqdordagi organizmlar, ehtimol ular ko'p hujayrali, ammo hech qanday zamonaviy organizmga o'xshamaydi.[21] 1948 yilda, Preston buluti Kembriyaning dastlabki davrida "portlash" evolyutsiyasi davri bo'lgan,[22] ammo o'tgan asrning 70-yillarida, O'rta va Oxirgi "nisbatan" zamonaviy ko'rinishga ega bo'lgan organizmlar to'g'risida hech qanday belgi ko'rilmadi. Kembriy paydo bo'ldi.[21]

Opabiniya Kembriyadagi portlashga zamonaviy qiziqish uchun eng katta yagona hissa qo'shdi.

Ushbu "kembriy portlashi" ga bo'lgan zamonaviy zamonaviy qiziqish Garri B. Uittington va hamkasblari, 1970-yillarda Burgess Slanetsdagi ko'plab qoldiqlarni qayta tahlil qilib, bir nechtasi har qanday tirik hayvonlar singari murakkab, ammo ulardan farq qiladi degan xulosaga kelishdi.[23][24] Eng keng tarqalgan organizm, Marrella, aniq edi artropod, ammo ma'lum bir artropod a'zosi emas sinf. Besh ko'zli kabi organizmlar Opabiniya va tikanoqqa o'xshash Wiwaxia Uttington jamoasi ma'lum bo'lgan har qanday narsadan shunchalik farq qilardiki, ular bugungi kunda ma'lum bo'lgan narsalarga aloqasi yo'qdek tuyulgan turli xil filalarni ifodalashlari kerak deb taxmin qilishdi. Stiven Jey Guld ushbu asarning 1989 yilgi mashhur hisoboti, Ajoyib hayot,[25] bu masalani jamoatchilik e'tiboriga havola etdi va portlash nimani anglatishi haqida savollar tug'dirdi. Uittington ham, Gould ham tafsilotlari jihatidan bir-biridan juda farq qilar edilar, barcha zamonaviy hayvonlar filasi deyarli bir vaqtning o'zida geologik davrda paydo bo'lgan deb taxmin qilishdi. Ushbu qarash Darvinning hayot daraxti va nazariyasini modernizatsiya qilishga olib keldi punktuatsiyalangan muvozanat, qaysi Eldredj va Guld 1970-yillarning boshlarida rivojlanib, evolyutsiyani qisqa vaqt ichida tez o'zgarib turadigan "to'xtab qolgan" staziyaga o'xshash uzoq vaqt oralig'ida ko'rib chiqadi.[26]

Boshqa tahlillar, ba'zilari yaqinroq va ba'zilari 1970-yillarga tegishli bo'lib, zamonaviy turlarga o'xshash murakkab hayvonlar kembriy boshlanishidan ancha oldin rivojlangan deb ta'kidlaydilar.[27][28][29]

Kembriy bilan uchrashish

Radiometrik jinslar tarkibidagi radioaktiv elementlarni tahlil qilish natijasida olingan Kembriyning katta qismi uchun sanalar yaqinda va faqat bir nechta mintaqalar uchun mavjud bo'ldi.

Nisbatan tanishish (A oldin bo'lgan B) ko'pincha evolyutsiya jarayonlarini o'rganish uchun etarli deb taxmin qilinadi, ammo bu ham qiyin bo'lgan, chunki bir xil yoshdagi jinslarni har xil bo'ylab moslashtirish bilan bog'liq muammolar mavjud qit'alar.[30]

Shu sababli, voqealar ketma-ketligi sanalari yoki tavsiflari yaxshilangan ma'lumotlarga ega bo'lguncha ehtiyotkorlik bilan ko'rib chiqilishi kerak.

Tana qoldiqlari

Organizmlarning tanalari qoldiqlari, odatda, ma'lumotlarning eng ma'lumotli turi hisoblanadi. Fosilizatsiya kamdan-kam uchraydigan hodisa bo'lib, aksariyat qoldiqlar ularni yo'q qiladi eroziya yoki metamorfizm ularni kuzatishdan oldin. Demak, fotoalbomlar juda to'liq emas, tobora oldingi davrlar ko'rib chiqilmoqda. Shunga qaramay, ular ko'pincha hayot tarixining kengroq namunalarini tasvirlash uchun etarli.[31] Fosil qoldiqlarida yonma-yonliklar mavjud: turli xil muhitlar har xil turdagi organizm yoki organizm qismlarini saqlab qolish uchun qulayroqdir.[32] Bundan tashqari, allaqachon mavjud bo'lgan organizmlarning faqat qismlari mineralizatsiyalangan kabukları kabi odatda saqlanib qoladi mollyuskalar. Hayvonlarning aksariyat turlari yumshoq tanaga ega bo'lganligi sababli, ular toshbo'ron bo'lishidan oldin parchalanadi. Natijada, tirik hayvonlarning 30 plyus filasi ma'lum bo'lsa-da, uchdan ikki qismi hech qachon qazilma sifatida topilmagan.[21]

Bu Marrella namunasi toshqotgan toshlar qanchalik aniq va batafsil tasvirlangan Burgess slanetsi Lagerstätte bor.

Kambriyenning qoldiqlari juda ko'p sonlarni o'z ichiga oladi lagerstätten, yumshoq to'qimalarni saqlaydigan. Bu imkon beradi paleontologlar boshqa cho'kindilarda faqat qobiq, tikanlar, tirnoqlar va boshqalar bilan ifodalanadigan hayvonlarning ichki anatomiyasini o'rganish - agar ular umuman saqlanib qolsa. Kembriyning eng muhim lagerstättenlari erta kembriylardir Maotianshan slanetsi Chenzzyan yotoqlari (Yunnan, Xitoy ) va Sirius Passet (Grenlandiya );[33] o'rta kembriy Burgess slanetsi (Britaniya Kolumbiyasi, Kanada );[34] va kech Kembriy Orsten (Shvetsiya ) fotoalbom yotoqlari.

Lagerstätten an'anaviy qoldiqlardan ancha ko'proq narsani saqlasa-da, ular hali tugallanmagan. Lagerstätten tor doirada cheklanganligi sababli (bu erda yumshoq tanali organizmlar juda tez saqlanib qolishi mumkin, masalan, loy toshqini bilan), aksariyat hayvonlar vakili emas; bundan tashqari, lagerstättenni yaratadigan istisno sharoitlar, ehtimol, normal yashash sharoitlarini anglatmaydi.[35] Bundan tashqari, ma'lum bo'lgan Kambriyen lagerstätten kamdan-kam uchraydi va hozirgi kungacha qiyin, prekambriyen lagerstätten esa hali batafsil o'rganilmagan.

Fosil qoldiqlarining siyrakligi shuni anglatadiki, organizmlar odatda toshqotganlikda topilishidan ancha oldin mavjud bo'lishadi - bu Signor-Lipps effekti.[36]

2019 yilda lagerstättenning "hayratlanarli" topilmasi Qingjiang biota, xabar qilindi Danshui daryosi yilda Xubey viloyat, Xitoy. 20 mingdan ortiq fotoalbom namunalari, shu jumladan meduzalar, dengiz anemonlari va qurtlar kabi ko'plab yumshoq tanali hayvonlar, shuningdek gubkalar, artropodlar va suv o'tlari to'plandi. Ba'zi namunalarda tana ichki tuzilmalari etarlicha saqlanib qolgan, ular yumshoq to'qimalarni, shu jumladan mushaklar, gillalar, og'izlar, ichak va ko'zlarni ko'rish mumkin. Qoldiqlar 518 Mya atrofida bo'lgan va xabar berish paytida aniqlangan turlarning yarmi ilgari noma'lum edi.[37][38][39]

Qoldiqlarning izi

Rusofik va boshqa iz qoldiqlari Gog guruhi, O'rta kembriy, Luiza ko'li, Alberta, Kanada

Qoldiqlarning izi asosan izlar va buruqlardan iborat, shuningdek, ularga kiradi koprolitlar (fotoalbom) najas ) va ovqatlanish paytida qoldirilgan belgilar.[40][41] Iz qoldiqlari ayniqsa ahamiyatlidir, chunki ular faqat qattiq qismlarga ega bo'lgan hayvonlar bilan chegaralanmagan va organizmlarning xatti-harakatlarini aks ettiradigan ma'lumotlar manbasini anglatadi. Bundan tashqari, ko'plab izlar, ularni yaratishga qodir deb hisoblangan hayvonlarning tana qoldiqlaridan ancha oldinroq bo'lgan.[42] Iz qoldiqlarini ularni ishlab chiqaruvchilariga aniq topshirish umuman imkonsiz bo'lsa-da, izlar, masalan, o'rtacha darajada murakkab hayvonlar paydo bo'lishining eng dastlabki ashyoviy dalillarini keltirishi mumkin (bilan taqqoslanadigan) yomg'ir qurtlari ).[41]

Geokimyoviy kuzatishlar

Asosiy maqola: Kembriyaning dastlabki geokimyoviy tebranishlari

Bir nechta kimyoviy belgilar Kembriy boshlanishi atrofidagi muhitning keskin o'zgarishini ko'rsatadi. Markerlar ommaviy yo'q bo'lib ketishga mos keladi,[43][44] yoki chiqarilishidan kelib chiqadigan katta issiqlik bilan metan muzi.[45]Bunday o'zgarishlar Kembriya portlashining sababini aks ettirishi mumkin, garchi ular biologik faollik darajasining ko'tarilishi natijasida yuzaga kelgan bo'lsa ham - portlashning mumkin bo'lgan natijasi.[45] Ushbu noaniqliklarga qaramay, geokimyoviy dalillar, olimlarning atrof-muhitdagi o'zgarishlarning kamida bittasiga mos keladigan nazariyalarga e'tibor qaratishlariga yordam beradi.

Filogenetik metodlar

Kladistika organizmlar to'plamining "nasl-nasab shajarasini" ishlab chiqish texnikasi. Bu mantiq asosida ishlaydi, agar B va C guruhlari bir-biriga o'xshash bo'lsa yoki A guruhiga ega bo'lsa, u holda B va C bir-birlari bilan emas, balki A bilan taqqoslanadi, taqqoslanadigan xususiyatlar anatomik, masalan, a notoxord, yoki molekulyar, ketma-ketliklarini taqqoslash orqali DNK yoki oqsil. Muvaffaqiyatli tahlil natijasi - bu ierarxiya qoplamalar - a'zolari umumiy ajdodlarga ega deb hisoblanadigan guruhlar. Kladistik texnika ba'zan muammoli bo'ladi, chunki ba'zi xususiyatlar, masalan qanotlar yoki kamera ko'zlari, bir necha bor rivojlangan, yaqinlashuvchi - bu tahlillarda hisobga olinishi kerak.

O'zaro munosabatlardan nasablar birinchi marta paydo bo'lgan sanani cheklash mumkin. Masalan, agar B yoki C qoldiqlari X million yil avval paydo bo'lgan bo'lsa va hisoblangan "nasl-nasab shajarasi" da A B va C ning ajdodi ekanligi aytilgan bo'lsa, unda A X million yildan ko'proq oldin rivojlangan bo'lishi kerak.

Bundan tashqari, DNKni taxmin qilib, ikki tirik to'qnashuv qancha vaqt oldin ajralib chiqqanligini, ya'ni ularning so'nggi umumiy ajdodi qancha yil yashagan bo'lishi mumkinligini taxmin qilish mumkin. mutatsiyalar doimiy tezlikda to'planadi. Bular "molekulyar soatlar "ammo, bu xato va faqat taxminiy vaqtni taqdim etadi: ular Kambriyadagi portlashda ishtirok etgan guruhlar qachon rivojlanganligini taxmin qilish uchun etarlicha aniq va ishonchli emas,"[46] va turli xil texnikalar asosida ishlab chiqarilgan taxminlar ikki baravar farq qiladi.[47] Shu bilan birga, soatlar dallanish tezligini ko'rsatishi mumkin va fotoalbomlar cheklovlari bilan birlashganda, so'nggi soatlar Ediakaran va Kembriy orqali diversifikatsiyaning barqaror davrini taklif qiladi.[48]

Asosiy ilmiy atamalarni tushuntirish

Ildiz guruhlari[49]
  • — = Chiqish chiziqlari
  •   = Bazal tugun
  •   = Crown tuguni
  •   = Jami guruh
  •   = Crown guruhi
  •   = Poyasi guruh

Filum

A filum ning eng yuqori darajasi Organizmlarni tasniflash uchun Linn sistemasi. Filani umumiy tana rejasi asosida hayvonlarni guruhlashi deb qarash mumkin.[50] Organizmlarning tashqi ko'rinishidan farqli o'laroq, ular ichki va rivojlanish tashkilotlariga qarab fitolarga bo'linadi.[51] Masalan, ularning aniq farqlariga qaramay, o'rgimchaklar va barnaklar ikkalasi ham Arthropoda filimiga tegishli, ammo yomg'ir qurtlari va lenta qurtlari shakli jihatidan o'xshash bo'lsa-da, har xil filaga tegishli. Kimyoviy va genetik tekshiruv yanada aniqroq bo'lganligi sababli, ilgari faraz qilingan fitol ko'pincha butunlay qayta ishlanadi.

Filum tabiatning asosiy bo'linishi emas, masalan, orasidagi farq elektronlar va protonlar. Bu shunchaki a-da juda yuqori darajadagi guruhlash tasniflash tizimi hozirgi barcha tirik organizmlarni tavsiflash uchun yaratilgan. Ushbu tizim, hatto zamonaviy hayvonlar uchun ham nomukammal: turli xil kitoblarda turli xil fillar keltirilgan, asosan, ular juda ko'p sonli qurtlarga o'xshash turlarning tasnifi to'g'risida kelishmovchiliklar mavjud. U tirik organizmlarga asoslanganligi sababli, yo'q bo'lib ketgan organizmlarni yomon joylashtiradi, agar umuman bo'lmasa.[21][52]

Ildiz guruhi

Tushunchasi ildiz guruhlari tirik guruhlarning evolyutsion "xolalari" va "amakivachchalari" ni qamrab olish uchun kiritilgan va ushbu ilmiy nazariya asosida faraz qilingan. A toj guruhi bir-biriga yaqin tirik hayvonlar guruhi va ularning so'nggi umumiy ajdodi va uning barcha avlodlari. Ildiz guruhi - bu toj guruhining so'nggi umumiy ajdodidan oldinroq bir nuqtada nasldan nasldan naslga o'tishlar to'plami; masalan, nisbiy tushuncha tardigradlar o'z-o'zidan toj guruhini tashkil etuvchi tirik hayvonlardir, ammo Budd (1996) ularni artropodlarga nisbatan ildiz guruhi deb hisoblagan.[49][53]

Celomat hayvon asosan ichak va tashqi naychalar orasidagi bo'shliqqa ega bo'lgan kontsentrik naychalar to'plamidir.

Triploblastik

Atama Triploblastik tarkibida hosil bo'lgan uchta qatlamdan iborat bo'lgan vositalar embrion, hayvonning rivojlanishida juda erta, bir hujayrali tuxumdan lichinka yoki balog'atga etmagan shaklgacha. Ichki qatlam oshqozon-ichak trakti (ichak); tashqi tomondan terini hosil qiladi; va o'rtasi mushaklarni va ovqat hazm qilish tizimidan tashqari barcha ichki organlarni hosil qiladi. Tirik hayvonlarning aksariyat turlari triploblastikdir - eng taniqli istisnolar Porifera (gubkalar) va Knidariya (meduzalar, dengiz anemonlari va boshqalar).

Bilaterian

The bilateriyaliklar hayot tarixida biron bir nuqtada o'ng va chap tomonlari bo'lgan hayvonlardir. Bu ularning yuqori va pastki yuzalariga va eng muhimi, old va orqa uchlari aniq bo'lishini anglatadi. Ma'lum bo'lgan ikki tomonlama hayvonlar triploblastik va ma'lum bo'lgan barcha triploblastik hayvonlar bilaterian. Yashash echinodermalar (dengiz yulduzlari, dengiz kirpi, dengiz bodringlari va hokazo.) "qarash" radikal nosimmetrik (g'ildiraklar kabi) emas, balki ikki tomonlama, ammo ularning lichinkalari ikki tomonlama simmetriyani namoyish etadi va ba'zi dastlabki echinodermalar ikki tomonlama nosimmetrik bo'lishi mumkin.[54] Porifera va Cnidaria radial nosimmetrikdir, bilaterian emas va triploblastik emas.

Coelomate

Atama Coelomate ichki organlarni o'z ichiga olgan tana bo'shlig'iga (koelom) ega bo'lishni anglatadi. Kambriyadagi portlash haqidagi munozarada aks etgan fitoning aksariyati[tushuntirish kerak ] kelomatlar: artropodlar, annelid qurtlar, mollyuskalar, echinodermalar va akkordatlar - nonkoelomat priapulidlar muhim istisno. Ma'lumki, barcha selomat hayvonlar triploblastik bilaterianlardir, ammo ba'zi triploblastik bilaterian hayvonlar koelomga ega emaslar - masalan yassi qurtlar, uning organlari bilan o'ralgan ixtisoslashtirilmagan to'qimalar.

Prekambriyalik hayot

Filogenetik tahlil Kembriyadagi portlash paytida metazoanlar (ko'p hujayrali hayvonlar) rivojlangan degan qarashni qo'llab-quvvatlash uchun foydalanilgan monofitik jihatdan bitta umumiy ajdoddan: bayroqlangan mustamlaka protistlar zamonaviyga o'xshash xanoflagellatlar.[iqtibos kerak ]

Taxminan 1 milliard yil oldin hayvonlarning dalillari

Qo'shimcha ma'lumotlar: Akritarx va Stromatolit
Stromatolitlar (Pika shakllanishi, O'rta kembriy) Xelen ko'li yaqinida, Banff milliy bog'i, Kanada
Zamonaviy stromatolitlar Hamelin Pool Dengiz qo'riqxonasi, G'arbiy Avstraliya

Qoldiqlarning ayrim turlarining ko'pligi va xilma-xilligidagi o'zgarishlar hayvonlar yoki boshqa organizmlarning "hujumlari" ga dalil sifatida talqin qilingan. Stromatolitlar, mustamlakalari tomonidan qurilgan poydevor ustunlar mikroorganizmlar, taxminan, fotoalbomlarning asosiy tarkibiy qismidir 2,700 million yil oldin, ammo ularning ko'pligi va xilma-xilligi keskin pasayib ketdi 1,250 million yil oldin. Ushbu pasayish hayvonlarni boqish va ko'mish natijasida buzilish bilan bog'liq.[27][28][55]

Prekambriyadagi dengiz xilma-xilligi sifatida tanilgan kichik toshqotganliklar ustunlik qilgan akritarxlar. Ushbu atama deyarli har qanday kichik organik devorli fotoalbomlarni tasvirlaydi - mayda tuxum holatlaridan metazoanlar dam olishga kistalar turli xil turlari yashil suv o'tlari. Atrofda paydo bo'lgandan keyin 2,000 million yil oldin, akritarxlar atrofida shov-shuv ko'tarildi 1,000 million yil oldin, mo'l-ko'lligi, xilma-xilligi, hajmi, shakli murakkabligi va ayniqsa, tikanlar hajmi va soni ko'payib boradi. So'nggi 1 milliard yil ichida ularning tobora ko'payib borayotgan shakllari yirtqich hayvonlardan himoya qilish ehtiyojining oshganligini ko'rsatishi mumkin. Dan kichik organizmlarning boshqa guruhlari Neoproterozoy davrda antipredator mudofaasi belgilari ham mavjud.[55] Taksonning uzoq umr ko'rishi shu davrda yirtqichlar bosimining oshishini qo'llab-quvvatlaydi.[56]Umuman olganda, fotoalbomlar ushbu hayot shakllarining Prekambriyada juda sekin ko'rinishini ko'rsatadi, chunki ko'plab siyanobakteriyalar turlari quyi qatlamlarning ko'p qismini tashkil qiladi.[57]

Doushantuo shakllanishining qoldiqlari

Asosiy maqola: Doushantuo shakllanishi

Qatlamlari Doushantuo shakllanishi atrofdan 580 million yillik[58]erta bilaterianlarni ifodalashi mumkin bo'lgan mikroskopik qoldiqlarni saqlang. Ba'zilar hayvon embrionlari va tuxumlari deb ta'riflangan, ammo ba'zilari ulkan bakteriyalarning qoldiqlarini aks ettirishi mumkin.[59]Boshqa bir qoldiq, Vernanimalkula, deb talqin qilingan kelishuv ikki tomonlama,[60]lekin shunchaki to'ldirilgan qabariq bo'lishi mumkin.[61]

Ushbu qoldiqlar, boshqa yirtqichlardan farqli o'laroq, hayvonlarning dastlabki tezkor dalillarini hosil qiladi.[59][62]

Burrows

Asosiy maqola: Kembriy substrat inqilobi
Ediakaran izlari qoldiqlari, a mikrobial mat.

Ediakaran dengiz tubini qoplagan mikrobial paspaslar ustida va to'g'ridan-to'g'ri ostida harakatlanadigan organizmlarning izlari Ediakar davridan saqlanib qolgan. 565 million yil oldin.[c] Ular, ehtimol, o'xshash organizmlar tomonidan yaratilgan yomg'ir qurtlari shakli, o'lchami va qanday harakat qilganliklari. Burrow ishlab chiqaruvchilari hech qachon saqlanib qolmaganlar, ammo ular bosh va dumga muhtoj bo'lishlari kerakligi sababli, burrowers, ehtimol, ikki tomonlama simmetriyaga ega edi - bu ularni ehtimol ikki tomonlama hayvonlarga aylantiradi.[65] Ular cho'kindi sathidan yuqori darajada oziqlangan, ammo yirtqichlardan qochish uchun burg'ulashga majbur bo'lgan.[66]

Kembriyaning boshlanishi atrofida (taxminan 542 million yil oldin) kabi izlarning ko'plab yangi turlari, shu jumladan taniqli vertikal burmalar paydo bo'ladi Diplocraterion va Skolitos va odatda artropodlarga tegishli izlar, masalan Kruziana va Rusofik. Vertikal burmalar shuni ko'rsatadiki, qurtga o'xshash hayvonlar yangi xatti-harakatlarni va ehtimol yangi jismoniy imkoniyatlarni egallashgan. Kembriyadagi ba'zi qoldiq qoldiqlar ularning ishlab chiqaruvchilari qattiq narsalarga ega ekanliklaridan dalolat beradi ekzoskeletlar, garchi ular mineralizatsiya qilinmasa ham.[64]

Burrows murakkab organizmlarning aniq dalillarini taqdim etadi; ular iz qoldiqlarining yo'qligi katta, harakatlanuvchi, tubida yashovchi organizmlarning chinakam yo'qligini nazarda tutgan holda, ular tana qoldiqlariga qaraganda ancha osonroq saqlanib qoladi.[iqtibos kerak ] Ular Kambriyadagi portlash haqiqiy diversifikatsiyani anglatishini va himoya asari emasligini ko'rsatadigan yana bir dalillarni keltiradi.[67]

Ushbu yangi odat dengiz tubining geokimyosini o'zgartirdi va okeandagi kislorodning pasayishiga va dengiz va atmosferadagi CO2 darajasining oshishiga olib keldi, natijada o'nlab million yillar davomida global isish yuz berdi va ommaviy qirg'in uchun javobgar bo'lishi mumkin.[68] Ammo burrowing o'rnatilgandan so'ng, bu o'z-o'zidan portlashiga yo'l qo'ydi, chunki burrowers dengiz tubini bezovta qilgani sababli, ular havoni chiqarib, zaharli loyga kislorod aralashtirdilar. Bu quyi cho'kindilarni yanada mehmondo'st holga keltirdi va organizmlarning keng doiralarida yashashiga imkon berdi - yangi joylar va yuqori xilma-xillik uchun imkoniyatlar yaratildi.[67]

Ediakaran organizmlari

Dikkinsoniya kostalari, noma'lum o'xshashligi bo'lgan Ediacaran organizmi, yopiq ko'rinishga ega
Asosiy maqolalar: Ediakara biota, Cloudinid, Kimberella va Spriggina

Ediakaran davrining boshida, asosan akritarx Yuz millionlab yillar davomida nisbatan o'zgarishsiz qolgan hayvonot dunyosi yo'q bo'lib ketdi, ularning o'rniga yangi, yirikroq turlar paydo bo'ldi, ular ancha vaqtinchalik ekanligini isbotlaydilar.[57] Fotoalbomlarda birinchi bo'lgan bu nurlanish,[57] Ko'p o'tmay Ediacara biota deb nomlangan noma'lum, yirik, toshqotganliklar qatori,[69] Kembriy boshlangunga qadar 40 million yil davomida gullab-yashnagan.[70] Ushbu "Ediacara biota" ning aksariyat qismi kamida bir necha santimetr uzunlikda bo'lib, avvalgi qoldiqlardan ancha katta bo'lgan. Organizmlar vaqt o'tishi bilan hajmi va murakkabligi oshib boradigan uchta aniq birikma hosil qiladi.[71]

Ushbu organizmlarning aksariyati ilgari yoki undan keyin paydo bo'lgan narsalarga, disklarga, loyga to'ldirilgan sumkalarga yoki tikilgan matraslarga o'xshash narsalarga o'xshamas edi - palonontologlardan biri g'alati organizmlarni alohida sifatida tasniflashni taklif qildi. qirollik, Vendozoa.[72]

Qoldiqlar Kimberella, triploblastik bilaterian va ehtimol mollyuska

Hech bo'lmaganda ba'zilari "kembriy portlashi" munozarasi markazida bo'lgan filaning dastlabki shakllari bo'lishi mumkin edi,[tushuntirish kerak ] erta mollyuskalar deb talqin qilingan (Kimberella ),[29][73] echinodermlar (Arkarua );[74] va artropodlar (Spriggina,[75] Parvancorina,[76] Yilingiya ). Hali ham ushbu namunalarni tasniflash borasida munozaralar mavjud, asosan, taksonomistlarga tirik organizmlarga o'xshashlik kabi so'nggi organizmlarni tasniflashga imkon beradigan diagnostika xususiyatlari odatda ediyakaranda yo'q.[77] Biroq, bunga shubha yo'q Kimberella hech bo'lmaganda triploblastik bilaterian hayvon edi.[77] Kembriyadagi portlash qanchalik keskin bo'lganligi haqidagi bahs-munozaralarda ushbu organizmlar markaziy o'rin tutadi.[iqtibos kerak ] Agar ba'zilari bugungi kunda ko'rilgan hayvonlar filosining dastlabki a'zolari bo'lgan bo'lsa, "portlash" bu organizmlarning barchasi bir-biriga bog'liq bo'lmagan "tajriba" ni anglatishiga qaraganda ancha to'satdan kamroq ko'rinadi va keyinchalik hayvonot dunyosi bilan juda tez orada almashtirildi (40 million yil "yaqinda") evolyutsion va geologik me'yorlar bo'yicha).

Bek bahosi Dolomit

Pol Knauth, geolog Arizona shtati universiteti, suv o'tlari kabi fotosintez qiluvchi organizmlar 750-800 million yillik shakllanish jarayonida o'sgan bo'lishi mumkin, deb ta'kidlaydi. O'lim vodiysi "Beck Spring Dolomit" nomi bilan tanilgan. 1990-yillarning boshlarida ushbu dolomitning qalinligi 1000 metr bo'lgan qatlamdan olingan namunalar shuni ko'rsatdiki, bu hududda fotosintez qiluvchi, bir hujayrali hayot shakllarining gullab-yashnagan matralari joylashgan bo'lib, ular Kambriyadagi portlashni tezlashtirgan.

Dolomitning aksincha bepusht yuzasini buzadigan teshiklardan mikrofosilalar topildi. Ushbu geokimyoviy va mikrofosil topilmalar Prekambriya davrida ham murakkab hayot okeanlarda ham, quruqlikda ham rivojlangan degan fikrni tasdiqlaydi. Kautning ta'kidlashicha, hayvonlar okeanlarda emas, balki chuchuk suvli ko'llarda va soylarda paydo bo'lishi mumkin.

Taxminan 30 yil o'tgach, bir qator tadqiqotlar hayotning 2,2 milliard yil oldin qit'alarni qamrab olganligini ko'rsatadigan ko'plab geokimyoviy va mikrofosil dalillarni hujjatlashtirdi. Hozirgi kunda ko'plab paleobiologlar oddiy hayot shakllari prekambriya davrida quruqlikda bo'lgan degan fikrni qabul qilmoqdalar, ammo 600 million yildan ko'proq vaqt oldin ko'p hujayrali hayot quruqlikda rivojlangan degan yanada radikal g'oyaga qarshi.[78]

Ediakaran – Kambriyenning dastlabki skeletlari topilishi

Birinchi Ediakaran va eng past kembriy (Nemakit-Daldyan ) skelet qoldiqlari naychalar va muammoli shimgichni spikulalarni ifodalaydi.[79] Eng qadimgi shimgichni spikulalari atrofida keksa, monaksonli kremniydir 580 million yil oldin, Xitoydagi Dushantou formasidan va Mo'g'ulistondagi o'sha yoshdagi konlardan ma'lum bo'lgan, ammo bu qoldiqlarni spikulalar deb talqin qilish qiyin bo'lgan.[80] Kechki Ediakarandan past bo'lgan Kembriyda sirli organizmlarning ko'plab naychali uylari paydo bo'ldi. Bu organik devorli quvurlar edi (masalan, Saarina ) va sabelliditidlarning xitinli naychalari (masalan. Sokoloviina, Sabellidlar, Paleolina)[81][82] boshiga qadar rivojlangan Tommotian. Ning minerallashgan naychalari Cloudina, Namakalat, Sinotubulitlar va Ediakaran davrining oxiriga kelib hosil bo'lgan karbonat jinslaridan boshqa o'nlab organizmlar 549 dan 542 gacha million yil oldin, shuningdek, anabaritidlarning tradialial nosimmetrik minerallashgan naychalari (masalan, Anabaritlar, Kambrotubulus) eng yuqori Ediakarandan va pastki Kembriydan.[83] Ediakaran mineralizatsiyalangan naychalari ko'pincha stromatolit riflarining karbonatlarida va trombolitlar,[84][85] ya'ni ular hayvonlarning aksariyat qismi uchun noqulay muhitda yashashi mumkin edi.

Garchi ularni boshqa Ediakaran organizmlari singari tasniflash qiyin bo'lsa ham, ular yana ikki jihatdan muhimdir. Birinchidan, ular ma'lum bo'lgan eng qadimgi kalsifikatsiya qiluvchi organizmlar (qobiq hosil qilgan organizmlar) kaltsiy karbonat ).[85][86][87] Ikkinchidan, bu quvurlar substrat va raqobatchilar ustidan ko'tarilib, samarali ovqatlanish uchun vositadir va ozroq darajada ular yirtqichlardan va atrof-muhitning salbiy sharoitlaridan himoya qilish uchun zirh vazifasini o'taydi. Biroz Cloudina fotoalbomlarda chig'anoqlarda kichik teshiklar bor. Teshiklar, ehtimol, chig'anoqlarga kirib borish uchun etarlicha rivojlangan yirtqichlar tomonidan zerikarli.[88] Mumkin "evolyutsion qurollanish poygasi "yirtqichlar va yirtqichlar o'rtasida - bu Kambriyadagi portlashni tushuntirishga urinayotgan gipotezalardan biri.[55]

Eng past kembriyda stromatolitlar parchalanib ketgan. Bu hayvonlarga karbonat cho'kindi bilan iliq suv havzalarini kolonizatsiya qilishni boshlashga imkon berdi. Avvaliga shunday bo'ldi anabaritidlar va Protohertzina (toshbo'ron qilingan kavisli tikanlar xetognatlar ) qoldiqlar. Chig'anoqlar, skleritlar, tikanlar va plitalar kabi mineral skeletlari eng yuqori qismida paydo bo'lgan Nemakit-Daldyan; ular eng qadimgi turlari bo'lgan halkieridlar, gastropodlar, golitlar va boshqa noyob organizmlar. Ning boshlanishi Tommotian tarixiy ravishda mollyuskalarning qoldiqlari sonining va turlarining portlovchi darajada ko'payishini belgilashga tushunilgan, golitlar va gubkalar, noma'lum hayvonlarning skelet elementlarining boy kompleksi bilan birga, birinchisi arxeoatsidlar, brakiyopodlar, tommotiidlar va boshqalar.[89][90][91][92] Shuningdek yumshoq tanli kabi mavjud bo'lgan phyla taroqli jele, skalidoforalar, entoproktanlar, taqa qurtlari va lobopodiyalar zirhli shakllarga ega edi.[93] Ushbu to'satdan o'sish qisman Tommotian tipidagi yo'qolgan qatlamlarning artefaktidir va bu faunaning aksariyati aslida Nemakit-Daldinyan va Tommotianga zarbalar qatorida diversifikatsiya qila boshladi.[94]

Ediakaranda ba'zi hayvonlarda allaqachon skleritlar, tikanlar va plitalar bo'lgan bo'lishi mumkin (masalan, Kimberella qattiq skleritlari bor edi, ehtimol karbonat), ammo ingichka karbonat skeletlari toshga aylanishi mumkin emas silikiklastik depozitlar.[95] Qadimgi (~ 750 mln.) Qoldiqlar mineralizatsiyaning Kembriyadan ancha oldin bo'lganligini, ehtimol kichik fotosintetik suv o'tlarini bir hujayrali ökaryotik yirtqichlardan himoya qilganligini ko'rsatadi.[96][97]

Kembriya hayoti

Qoldiqlarning izi

Qoldiq izlari (burmalar va boshqalar) hayot qanday bo'lganining ishonchli ko'rsatkichidir va Kembriy boshlanishida hayotning xilma-xilligini ko'rsatadi, chuchuk suv sohasi okeanlar singari hayvonlar tomonidan mustamlakaga aylanadi.[98]

Kichik qobiqli fauna

Asosiy maqola: Kichik qobiqli fauna

"Qoldiqlar" nomi bilan tanilgankichik qobiqli fauna "dunyoning ko'plab joylarida topilgan va kembriydan oldingi kembriy boshlanganidan taxminan 10 million yilgacha ( Nemakit-Daldyan va Tommotian yoshi; qarang vaqt jadvali ). Bu qoldiqlarning juda aralash kollektsiyasi: tikanlar, skleritlar (zirh plitalari), naychalar, arxeoatidlar (shimgichga o'xshash hayvonlar), va ular kabi kichik chig'anoqlar brakiyopodlar va salyangozga o'xshash mollyuskalar - ammo barchasi mayda, asosan uzunligi 1 dan 2 mm gacha.[99]

Kichkina bo'lsa ham, bu qoldiqlar ularni hosil qilgan organizmlarning to'liq qoldiqlariga qaraganda ancha keng tarqalgan; eng muhimi, ular kembriyning boshlanishidan birinchi lagerstättengacha bo'lgan oynani yopib qo'yishadi: aks holda qoldiqlarda etishmayotgan vaqt. Shunday qilib, ular odatdagi fotoalbomlarni to'ldiradi va ko'plab guruhlarning qoldiqlari oralig'ini kengaytirishga imkon beradi.

Kembriyaning dastlabki trilobitlari va echinodermalari

Qadimgi turi bo'lgan toshbo'ron qilingan trilobit artropod: Burgess Shale-dan olingan ushbu namunada "yumshoq qismlar" - antennalar va oyoqlar saqlanib qolgan.

Eng qadimgi trilobit fotoalbomlarning yoshi taxminan 530 million yilni tashkil etadi, ammo bu sinf allaqachon juda xilma-xil va dunyo miqyosida bo'lgan, bu ularning ancha vaqtdan beri mavjudligini anglatadi.[100]Trilobitlarning qoldiqlari minerallar ekzoskeletlari bo'lgan trilobitlar paydo bo'lishidan boshlangan - ular paydo bo'lgan paytdan emas.

Dastlab qabul qilingan echinoderm qoldiqlari birozdan keyin, kechroq vaqtlarda paydo bo'lgan Atdabanian; zamonaviy echinodermalardan farqli o'laroq, bu dastlabki kambiyalik echinodermalar hammasi radial nosimmetrik bo'lmagan.[101]

Bular portlashning "tugashi" uchun aniq ma'lumot punktlarini yoki hech bo'lmaganda zamonaviy filaning toj guruhlari vakili bo'lganligini ko'rsatib beradi.

Burgess slanets tipidagi faunalar

Asosiy maqola: Burgess slanets turini saqlash

Burgess Slanets va shunga o'xshash lagerstätten organizmlarning yumshoq qismlarini saqlaydi, ular sirli qoldiqlarni tasniflashda juda ko'p ma'lumot beradi. U tez-tez tarqalgan qismlardan, masalan, bo'shashgan tarozi yoki ajratilgan og'iz qismlaridan boshqa ma'lum bo'lgan organizmlarning to'liq namunalarini saqlab qoldi. Bundan tashqari, ushbu ufqlardagi organizmlar va taksonlarning aksariyati butunlay yumshoq tanadir, shuning uchun qoldiq qoldiqlarida yo'q.[102] Ekotizimning katta qismi saqlanib qolganligi sababli, jamiyat ekologiyasi ham taxminiy ravishda tiklanishi mumkin.[tekshirish kerak ]Shu bilan birga, yig'ilishlar "muzey" ni anglatishi mumkin: chuqurroq ekotizim, evolyutsion ravishda sayoz suvlarning tez xilma-xil bo'lgan faunasi "orqasida".[103]

Lagerstätten saqlanish rejimi va sifatini Kembriydan tashqarida deyarli mavjud emasligi sababli, ko'plab organizmlar odatdagi fotoalbomlardan ma'lum bo'lgan narsalardan butunlay farq qiladi. Bu daladagi dastlabki ishchilarni organizmlarni oyoq osti qiladigan filaga aylantirishga urinishlariga olib keldi; Ushbu yondashuvning kamchiliklari keyinchalik ishchilarni barcha g'alati to'plarni joylashtirish uchun ko'plab yangi filalarni o'rnatishga olib keldi. O'shandan beri g'alati to'plarning aksariyati ajralib turishi aniqlandi nasablar ular bugungi kunda ma'lum bo'lgan filani o'rnatmasdan oldin[tushuntirish kerak ] - qarindoshlarining avlodlari singari, pillaga aylanib ketishdan ko'ra yo'q bo'lib ketishga mo'ljallangan bir oz boshqacha dizaynlar.

Himoyalash tartibi avvalgi Ediakaran davrida kamdan-kam uchraydi, ammo ma'lum bo'lgan ushbu birikmalar hayvonot dunyosidan hech qanday iz qoldirmaydi, ehtimol bu makroskopik metazoanlarning haqiqiy yo'qligini anglatadi.[104]

Kambriyalik qisqichbaqasimonlar

Qo'shimcha ma'lumotlar: Orsten

Artropodlarning zamonaviy to'rtta buyuk guruhlaridan biri bo'lgan qisqichbaqasimonlar butun Kembriya bo'ylab juda kam uchraydi. Ishonchli qisqichbaqasimonlar ilgari Burgess Shale tipidagi biotalarda keng tarqalgan deb o'ylashgan, ammo bu shaxslarning hech biri "haqiqiy qisqichbaqasimonlar" toj guruhiga kirishini ko'rsatib bo'lmaydi.[105] Kambriyadagi toj guruhi qisqichbaqasimonlar yozuvlari mikrofosillardan olingan. Shved Orsten ufqlarda keyinchalik Kembriya qisqichbaqasimonlar mavjud, ammo faqat 2 mm dan kichik organizmlar saqlanib qolgan. Bu voyaga etmaganlar va kichraytirilgan kattalar uchun ma'lumotlar to'plamini cheklaydi.

Ma'lumotli ma'lumot manbai - bu organik mikrofosillalar Qopqoqning shakllanishi, Makkenzi tog'lari, Kanada. Ushbu kech Kembriyning dastlabki yig'ilishi (510 dan 515 gacha million yil oldin) artropodlar kutikulasining mikroskopik bo'laklaridan tashkil topgan bo'lib, u jinslar bilan eritilganda ortda qoladi. gidroflorik kislota. Ushbu to'plamning xilma-xilligi zamonaviy qisqichbaqasimon faunalarga o'xshaydi. Formada topilgan oziqlantiruvchi texnika parchalarining tahlili shuni ko'rsatadiki, u juda aniq va tozalangan holda boqishga moslashgan. Bu boshqa Kembriy artropodlarining aksariyatiga qarama-qarshi bo'lib, ular oziqlantiruvchi qo'shimchalarini og'ziga olishlari mumkin bo'lgan har qanday narsani belkurak bilan bemalol oziqlantirgan. Ushbu murakkab va ixtisoslashtirilgan oziqlantirish texnikasi katta (taxminan 30 sm) ga tegishli edi.[106] organizm va diversifikatsiya qilish uchun katta imkoniyatlar yaratgan bo'lar edi; ixtisoslashtirilgan oziqlantirish apparati ovqatlanish va rivojlanish uchun bir qator turli xil yondashuvlarga imkon beradi va ovqatlanmaslik uchun bir qator turli xil yondashuvlarni yaratadi.[105]

Dastlabki Ordovik radiatsiyasi

Asosiy maqola: Ordovik radiatsiyasi

Keyin yo'q bo'lib ketish Kambriyen-Ordovik chegarasida paleozoyda hukmronlik qiladigan taksonlarni o'rnatgan yana bir nurlanish paydo bo'ldi.[107]

Ushbu nurlanish paytida buyurtmalarning umumiy soni ikki baravar, oilalar esa uch baravar ko'paydi,[107] dengiz xilma-xilligini paleozoyga xos darajalarga oshirish,[45] va bugungi kunga teng keladigan darajadagi nomutanosiblik.[11]

Bosqichlar

Tadbir taxminan 20 kun davom etdi[5][108]–25[109][110] million yil va evolyutsiyaning yuqori sur'atlari Kembriya seriyasi 2 tomonidan tugagan edi, 521 million yil oldin, fotoalbomlarda birinchi trilobitlarga to'g'ri keldi.[111] Turli xil mualliflar portlashni turli yo'llar bilan bosqichlarga ajratadilar.

Ed Landing uch bosqichni tan oladi: Ediakaran-Kembriya chegarasini o'z ichiga olgan 1-bosqich, biomineralizatsiya qiluvchi hayvonlar va chuqur va murakkab burmalarning diversifikatsiyasiga to'g'ri keladi; Mollyuskalar va poyalar guruhi nurlanishiga mos keladigan 2-bosqich Brakiyopodlar (golitlar va tommotiidlar ), ular intervalgacha suvlarda paydo bo'lgan; and Stage 3, seeing the Atdabanian diversification of trilobites in deeper waters, but little change in the intertidal realm.[112]

Grem Budd synthesises various schemes to produce a compatible view of the SSF record of the Cambrian explosion, divided slightly differently into four intervals: a "Tube world", lasting from 550 to 536 million yil oldin, spanning the Ediacaran-Cambrian boundary, dominated by Cloudina, Namacalathus and pseudoconodont-type elements; a "Sclerite world", seeing the rise of halkieriids, tommotiids, and hyoliths, lasting to the end of the Fortunian (c. 525 Ma); a brachiopod world, perhaps corresponding to the as yet unratified Cambrian Stage 2; and Trilobite World, kicking off in Stage 3.[113]

Complementary to the shelly fossil record, trace fossils can be divided into five subdivisions: "Flat world" (late Ediacaran), with traces restricted to the sediment surface; Protreozoic III (after Jensen), with increasing complexity; pedum world, initiated at the base of the Cambrian with the base of the T.pedum zone (see discussion at Cambrian#Dating the Cambrian ); Rusofik world, spanning 536 to 521 million yil oldin and thus corresponding exactly to the periods of Sclerite World and Brachiopod World under the SSF paradigm; va Kruziana world, with an obvious correspondence to Trilobite World.[113]

Amal qilish muddati

There is strong evidence for species of Knidariya va Porifera mavjud bo'lgan Ediakaran[114] and possible members of Porifera even before that during the Kriogen.[115] Bryozoanlar don't appear in the fossil record until after the Cambrian, in the Lower Ordovik.[116]

The fossil record as Darwin knew it seemed to suggest that the major metazoan groups appeared in a few million years of the early to mid-Cambrian, and even in the 1980s, this still appeared to be the case.[24][25]

However, evidence of Precambrian Metazoa is gradually accumulating. If the Ediacaran Kimberella was a mollusc-like protostom (one of the two main groups of coelomates ),[29][73] the protostome and deuterostom lineages must have split significantly before 550 million yil oldin (deuterostomes are the other main group of coelomates).[117] Even if it is not a protostome, it is widely accepted as a bilaterian.[77][117] Since fossils of rather modern-looking cnidarians (meduza -like organisms) have been found in the Doushantuo lagerstätte, the cnidarian and bilaterian lineages must have diverged well over 580 million yil oldin.[117]

Qoldiqlarning izi[71] and predatory borings in Cloudina shells provide further evidence of Ediacaran animals.[118] Some fossils from the Doushantuo formation have been interpreted as embryos and one (Vernanimalkula ) as a bilaterian coelomate, although these interpretations are not universally accepted.[60][61][119] Earlier still, predatory pressure has acted on stromatolites and acritarchs since around 1,250 million yil oldin.[55]

Some say that the evolutionary change was accelerated by an kattalik tartibi,[d] but the presence of Precambrian animals somewhat dampens the "bang" of the explosion; not only was the appearance of animals gradual, but their evolyutsion nurlanish ("diversification") may also not have been as rapid as once thought. Indeed, statistical analysis shows that the Cambrian explosion was no faster than any of the other radiations in animals' history.[e] However, it does seem that some innovations linked to the explosion – such as resistant armour – only evolved once in the animal lineage; this makes a lengthy Precambrian animal lineage harder to defend.[121] Further, the conventional view that all the phyla arose in the Cambrian is flawed; while the phyla may have diversified in this time period, representatives of the crown groups of many phyla do not appear until much later in the Phanerozoic.[12] Further, the mineralised phyla that form the basis of the fossil record may not be representative of other phyla, since most mineralised phyla originated in a bentik sozlash. The fossil record is consistent with a Cambrian explosion that was limited to the benthos, with pelagic phyla evolving much later.[12]

Ecological complexity among marine animals increased in the Cambrian, as well later in the Ordovician.[11] However, recent research has overthrown the once-popular idea that disparity was exceptionally high throughout the Cambrian, before subsequently decreasing.[122] In fact, disparity remains relatively low throughout the Cambrian, with modern levels of disparity only attained after the early Ordovician radiation.[11]

The diversity of many Cambrian assemblages is similar to today's,[123][105] and at a high (class/phylum) level, diversity is thought by some to have risen relatively smoothly through the Cambrian, stabilizing somewhat in the Ordovician.[124] This interpretation, however, glosses over the astonishing and fundamental pattern of basal polotomiya and phylogenetic telescoping at or near the Cambrian boundary, as seen in most major animal lineages.[125] Shunday qilib Garri Blekmor Uittington 's questions regarding the abrupt nature of the Cambrian explosion remain, and have yet to be satisfactorily answered.[126]

The Cambrian explosion as survivorship bias

Budd and Mann[127] suggested that the Cambrian explosion was the result of a type of omon qolish uchun tarafkashlik "deb nomlanganO'tmish suring ". As groups at their origin tend to go extinct, it follows that any long-lived group would have experienced an unusually rapid rate of diversification early on, creating the illusion of a general speed-up in diversification rates. However, rates of diversification could remain at background levels and still generate this sort of effect in the surviving lineages.

Mumkin sabablar

Despite the evidence that moderately complex animals (triploblastik bilateriyaliklar ) existed before and possibly long before the start of the Cambrian, it seems that the pace of evolution was exceptionally fast in the early Cambrian. Possible explanations for this fall into three broad categories: environmental, developmental, and ecological changes. Any explanation must explain both the timing and magnitude of the explosion.

Changes in the environment

Increase in oxygen levels

Earth's earliest atmosphere contained no free kislorod (O2); the oxygen that animals breathe today, both in the air and dissolved in water, is the product of billions of years of fotosintez. Cyanobacteria were the first organisms to evolve the ability to photosynthesize, introducing a steady supply of oxygen into the environment.[128] Initially, oxygen levels did not increase substantially in the atmosphere.[129] The oxygen quickly reacted with iron and other minerals in the surrounding rock and ocean water. Once a saturation point was reached for the reactions in rock and water, oxygen was able to exist as a gas in its diatomic form. Oxygen levels in the atmosphere increased substantially afterward.[130] As a general trend, the diqqat of oxygen in the atmosphere has risen gradually over about the last 2.5 billion years.[21]

Oxygen levels seem to have a positive correlation with diversity in eukaryotes well before the Cambrian period.[131] The last common ancestor of all extant eukaryotes is thought to have lived around 1.8 billion years ago. Around 800 million years ago, there was a notable increase in the complexity and number of eukaryotes species in the fossil record.[131] Before the spike in diversity, eukaryotes are thought to have lived in highly sulfuric environments. Sulfide interferes with mitochondrial function in aerobic organisms, limiting the amount of oxygen that could be used to drive metabolism. Oceanic sulfide levels decreased around 800 million years ago, which supports the importance of oxygen in eukaryotic diversity.[131]

The shortage of oxygen might well have prevented the rise of large, complex animals. The amount of oxygen an animal can absorb is largely determined by the area of its oxygen-absorbing surfaces (lungs and gills in the most complex animals; the skin in less complex ones); but, the amount needed is determined by its volume, which grows faster than the oxygen-absorbing area if an animal's size increases equally in all directions. An increase in the concentration of oxygen in air or water would increase the size to which an organism could grow without its tissues becoming starved of oxygen. However, members of the Ediacara biota reached metres in length tens of millions of years before the Cambrian explosion.[43] Other metabolic functions may have been inhibited by lack of oxygen, for example the construction of tissue such as kollagen, required for the construction of complex structures,[132] or to form molecules for the construction of a hard exoskeleton.[133] However, animals were not affected when similar oceanographic conditions occurred in the Phanerozoic; there is no convincing correlation between oxygen levels and evolution, so oxygen may have been no more a prerequisite to complex life than liquid water or primary productivity.[134]

Ozone formation

The amount of ozone (O3) required to shield Earth from biologically lethal UV radiation, wavelengths from 200 to 300 nanometers (nm), is believed to have been in existence around the Cambrian explosion.[135] Ning mavjudligi ozon qatlami may have enabled the development of complex life and life on land, as opposed to life being restricted to the water.

Snowball Earth

Asosiy maqola: Snowball Earth

Kech Neoproterozoy (extending into the early Ediakaran period), the Earth suffered massive glaciations in which most of its surface was covered by ice. This may have caused a mass extinction, creating a genetic bottleneck; the resulting diversification may have given rise to the Ediakara biota, which appears soon after the last "Snowball Earth" episode.[136]However, the snowball episodes occurred a long time before the start of the Cambrian, and it is difficult to see how so much diversity could have been caused by even a series of bottlenecks;[45] the cold periods may even have kechiktirildi the evolution of large size organisms.[55]

Increase in the calcium concentration of the Cambrian seawater

Newer research suggests that volcanically active midocean ridges caused a massive and sudden surge of the calcium concentration in the oceans, making it possible for marine organisms to build skeletons and hard body parts.[137]Alternatively a high influx of ions could have been provided by the widespread erosion that produced Powell's Katta nomuvofiqlik.[138]

An increase of calcium may also have been caused by erosion of the Transgondwanan Supermountain that existed at the time of the explosion. The roots of the mountain are preserved in present-day Sharqiy Afrika sifatida orogen.[139]

Developmental explanations

Qo'shimcha ma'lumotlar: Evolyutsion rivojlanish biologiyasi

A range of theories are based on the concept that minor modifications to animals' development as they grow from embrion to adult may have been able to cause very large changes in the final adult form. The Hox genlari, for example, control which organs individual regions of an embryo will develop into. For instance, if a certain Xox gene is expressed, a region will develop into a limb; if a different Hox gene is expressed in that region (a minor change), it could develop into an eye instead (a phenotypically major change).

Such a system allows a large range of disparity to appear from a limited set of genes, but such theories linking this with the explosion struggle to explain why the origin of such a development system should by itself lead to increased diversity or disparity. Evidence of Precambrian metazoans[45] combines with molecular data[140] to show that much of the genetic architecture that could feasibly have played a role in the explosion was already well established by the Cambrian.

This apparent paradox is addressed in a theory that focuses on the fizika rivojlanish. It is proposed that the emergence of simple multicellular forms provided a changed context and spatial scale in which novel physical processes and effects were mobilized by the products of genes that had previously evolved to serve unicellular functions. Morphological complexity (layers, segments, lumens, appendages) arose, in this view, by o'z-o'zini tashkil etish.[141]

Genlarni gorizontal ravishda uzatish has also been identified as a possible factor in the rapid acquisition of the biochemical capability of biomineralization among organisms during this period, based on evidence that the gene for a critical protein in the process was originally transferred from a bacterium into sponges.[142]

Ecological explanations

These focus on the interactions between different types of organism. Some of these hypotheses deal with changes in the Oziq ovqat zanjiri; some suggest qurol poygalari between predators and prey, and others focus on the more general mechanisms of koevolyutsiya. Such theories are well suited to explaining why there was a rapid increase in both disparity and diversity, but they do not explain why the "explosion" happened when it did.[45]

End-Ediacaran mass extinction

Asosiy maqola: Ediakaraning yo'q bo'lib ketishi

Evidence for such an extinction includes the disappearance from the fossil record of the Ediacara biota and shelly fossils such as Cloudina, and the accompanying perturbation in the δ13C yozuv. It is suspected that several global anoxic events were responsible for the extinction.[143][144]

Mass extinctions are often followed by moslashuvchan nurlanishlar as existing clades expand to occupy the ecospace emptied by the extinction. However, once the dust had settled, overall disparity and diversity returned to the pre-extinction level in each of the Phanerozoic extinctions.[45]

Anoksiya

The late Ediacaran oceans appears to have suffered from an anoksiya that covered much of the seafloor, which would have given mobile animals able to seek out more oxygen-rich environments an advantage over sessile forms of life.[145]

Evolution of eyes

Asosiy maqola: Ko'zning rivojlanishi

Endryu Parker has proposed that predator-prey relationships changed dramatically after eyesight evolved. Prior to that time, hunting and evading were both close-range affairs – smell, vibration, and touch were the only senses used. When predators could see their prey from a distance, new defensive strategies were needed. Armor, spines, and similar defenses may also have evolved in response to vision. He further observed that, where animals lose vision in unlighted environments such as caves, diversity of animal forms tends to decrease.[146] Nevertheless, many scientists doubt that vision could have caused the explosion. Eyes may well have evolved long before the start of the Cambrian.[147] It is also difficult to understand why the evolution of eyesight would have caused an explosion, since other senses, such as smell and pressure detection, can detect things at a greater distance in the sea than sight can; but the appearance of these other senses apparently did not cause an evolutionary explosion.[45]

Arms races between predators and prey

The ability to avoid or recover from yirtqichlik often makes the difference between life and death, and is therefore one of the strongest components of tabiiy selektsiya. The pressure to adapt is stronger on the prey than on the predator: if the predator fails to win a contest, it loses a meal; if the prey is the loser, it loses its life.[148]

But, there is evidence that predation was rife long before the start of the Cambrian, for example in the increasingly spiny forms of acritarchs, the holes drilled in Cloudina shells, and traces of burrowing to avoid predators. Hence, it is unlikely that the tashqi ko'rinish of predation was the trigger for the Cambrian "explosion", although it may well have exhibited a strong influence on the body forms that the "explosion" produced.[55] However, the intensity of predation does appear to have increased dramatically during the Cambrian[149] as new predatory "tactics" (such as shell-crushing) emerged.[150] This rise of predation during the Cambrian was confirmed by the temporal pattern of the median predator ratio at the scale of genus, in fossil communities covering the Cambrian and Ordovician periods, but this pattern is not correlated to diversification rate.[151] This lack of correlation between predator ratio and diversification over the Cambrian and Ordovician suggests that predators did not trigger the large evolutionary radiation of animals during this interval. Thus the role of predators as triggerers of diversification may have been limited to the very beginning of the "Cambrian explosion".[151]

Increase in size and diversity of planktonic animals

Geokimyoviy evidence strongly indicates that the total mass of plankton has been similar to modern levels since early in the Proterozoic. Before the start of the Cambrian, their corpses and droppings were too small to fall quickly towards the seabed, since their sudrab torting was about the same as their weight. This meant they were destroyed by tozalovchilar or by chemical processes before they reached the sea floor.[35]

Mesozooplankton are plankton of a larger size. Early Cambrian specimens filtrlangan microscopic plankton from the seawater. These larger organisms would have produced droppings and ultimately corpses large enough to fall fairly quickly. This provided a new supply of energy and nutrients to the mid-levels and bottoms of the seas, which opened up a new range of possible ways of life. If any of these remains sank uneaten to the sea floor they could be buried; this would have taken some uglerod tashqarida tiraj, resulting in an increase in the diqqat of breathable oxygen in the seas (carbon readily kombaynlar with oxygen).[35]

The initial herbivorous mesozooplankton were probably larvae of benthic (seafloor) animals. A larval stage was probably an evolutionary innovation driven by the increasing level of predation at the seafloor during the Ediakaran davr.[10][152]

Metazoans have an amazing ability to increase diversity through koevolyutsiya.[57] This means that an organism's traits can lead to traits evolving in other organisms; a number of responses are possible, and a different species can potentially emerge from each one. As a simple example, the evolution of predation may have caused one organism to develop a defence, while another developed motion to flee. This would cause the predator lineage to diverge into two species: one that was good at chasing prey, and another that was good at breaking through defences. Actual coevolution is somewhat more subtle, but, in this fashion, great diversity can arise: three quarters of living species are animals, and most of the rest have formed by coevolution with animals.[57]

Ecosystem engineering

Evolving organisms inevitably change the environment they evolve in. The Devoniy colonization of land had planet-wide consequences for sediment cycling and ocean nutrients, and was likely linked to the Devonian mass extinction. A similar process may have occurred on smaller scales in the oceans, with, for example, the sponges filtering particles from the water and depositing them in the mud in a more digestible form; or burrowing organisms making previously unavailable resources available for other organisms.[153]

Complexity threshold

The explosion may not have been a significant evolutionary event. It may represent a threshold being crossed: for example a threshold in genetic complexity that allowed a vast range of morphological forms to be employed.[154] This genetic threshold may have a correlation to the amount of oxygen available to organisms. Using oxygen for metabolism produces much more energy than anaerobic processes. Organisms that use more oxygen have the opportunity to produce more complex proteins, providing a template for further evolution.[129] These proteins translate into larger, more complex structures that allow organisms better to adapt to their environments.[155] With the help of oxygen, genes that code for these proteins could contribute to the expression of murakkab xususiyatlar yanada samarali. Access to a wider range of structures and functions would allow organisms to evolve in different directions, increasing the number of niches that could be inhabited. Furthermore, organisms had the opportunity to become more specialized in their own niches.[155]

Uniqueness of the explosion

The "Cambrian explosion" can be viewed as two waves of metazoan expansion into empty niches: first, a koevolyutsion rise in diversity as animals explored niches on the Ediacaran sea floor, followed by a second expansion in the early Cambrian as they became established in the water column.[57] The rate of diversification seen in the Cambrian phase of the explosion is unparalleled among marine animals: it affected all metazoan qoplamalar of which Cambrian fossils have been found. Keyinchalik nurlanish, masalan baliq ichida Siluriya va Devoniy periods, involved fewer taksonlar, mainly with very similar body plans.[21] Although the recovery from the Permian-triasning yo'q bo'lib ketishi started with about as few animal species as the Cambrian explosion, the recovery produced far fewer significantly new types of animals.[156]

Whatever triggered the early Cambrian diversification opened up an exceptionally wide range of previously unavailable ekologik uyalar. When these were all occupied, limited space existed for such wide-ranging diversifications to occur again, because strong competition existed in all niches and amaldagi rahbarlar usually had the advantage. If a wide range of empty niches had continued, clades would be able to continue diversifying and become disparate enough for us to recognise them as different fitna; when niches are filled, lineages will continue to resemble one another long after they diverge, as limited opportunity exists for them to change their life-styles and forms.[157]

There were two similar explosions in the evolution of land plants: after a cryptic history beginning about 450 million yil oldin, land plants underwent a uniquely rapid adaptive radiation during the Devonian period, about 400 million yil oldin.[21] Furthermore, angiosperms (gullarni o'simliklar ) originated and rapidly diversified during the Bo'r davr.

Shuningdek qarang

Izohlar

  1. ^ This included at least animals, fitoplankton va kaltsimikroblar.[10]
  2. ^ At 610 million years ago, Aspidella disks appeared, but it is not clear that these represented complex life forms.
  3. ^ Older marks found in billion-year-old rocks[63] have since been recognised as nonbiogenic.[12][64]
  4. ^ As defined in terms of the extinction and origination rate of species.[57]
  5. ^ The analysis considered the bioprovinciality of trilobite lineages, as well as their evolutionary rate.[120]

Adabiyotlar

  1. ^ Zhuravlev, Andrey; Riding, Robert (2000). The Ecology of the Cambrian Radiation. Kolumbiya universiteti matbuoti. ISBN  978-0-231-10613-9. The Cambrian radiation was the explosive evolution of marine life that started 550,000,000 years ago. It ranks as one of the most important episodes in Earth history. This key event in the hayot tarixi on our planet changed the marine biosphere and its sedimentary environment forever, requiring a complex interplay of wide-ranging biologic and nonbiologic processes.
  2. ^ Maloof, A. C.; Porter, S. M.; Mur, J. L .; Dudas, F. O.; Bowring, S. A.; Higgins, J. A.; Fike, D. A.; Eddy, M. P. (2010). "The earliest Cambrian record of animals and ocean geochemical change". Geologiya jamiyati Amerika byulleteni. 122 (11–12): 1731–1774. Bibcode:2010GSAB..122.1731M. doi:10.1130/B30346.1.
  3. ^ "New Timeline for Appearances of Skeletal Animals in Fossil Record Developed by UCSB Researchers". Kaliforniya Universitetining Regentslari. 2010 yil 10-noyabr. Olingan 1 sentyabr 2014.
  4. ^ Calibrating rates of early Cambrian evolution, Science 1993, 261(5126), s. 1293–1298. SA Bowring, JP Grotzinger, CE Isachsen, AH Knoll, SM Pelechaty, P Kolosov
  5. ^ a b Valentine, JW; Jablonski, D; Erwin, DH (1999). "Fossils, molecules and embryos: new perspectives on the Cambrian explosion". Rivojlanish. 126 (5): 851–9. PMID  9927587.
  6. ^ Budd, Graham (2013). "At the origin of animals: the revolutionary cambrian fossil record". Hozirgi Genomika. 14 (6): 344–354. doi:10.2174/13892029113149990011. PMC  3861885. PMID  24396267.
  7. ^ Erwin, D. H.; Laflamme, M.; Tvidt, S. M.; Sperling, E. A .; Pisani, D .; Peterson, K. J. (2011). "The Cambrian conundrum: early divergence and later ecological success in the early history of animals". Ilm-fan. 334 (6059): 1091–1097. Bibcode:2011Sci...334.1091E. doi:10.1126 / science.1206375. PMID  22116879. S2CID  7737847.
  8. ^ Kouchinskiy, A .; Bengtson, S .; Runnegar, B. N .; Skovsted, C. B.; Shtayner, M .; Vendrasco, M. J. (2012). "Chronology of early Cambrian biomineralization". Geologik jurnal. 149 (2): 221–251. Bibcode:2012GeoM..149..221K. doi:10.1017/s0016756811000720.
  9. ^ Konvey Morris, S. (2003). "The Cambrian "explosion" of metazoans and molecular biology: would Darwin be satisfied?". Rivojlanish biologiyasining xalqaro jurnali. 47 (7–8): 505–15. PMID  14756326.
  10. ^ a b Butterfield, N.J. (2001). "Ecology and evolution of Cambrian plankton" (PDF). The Ecology of the Cambrian Radiation. Nyu-York: Kolumbiya universiteti matbuoti. pp. 200–216. ISBN  978-0-231-10613-9. Olingan 2007-08-19.
  11. ^ a b v d Bambach, R.K.; Bush, A.M.; Erwin, D.H. (2007). "Autecology and the filling of Ecospace: Key metazoan radiations". Palæontology. 50 (1): 1–22. doi:10.1111/j.1475-4983.2006.00611.x.
  12. ^ a b v d Budd, G. E .; Jensen, S. (2000). "Ikki tomonlama filaning toshqotganliklarini tanqidiy qayta baholash". Kembrij falsafiy jamiyati biologik sharhlari. 75 (2): 253–95. doi:10.1111 / j.1469-185X.1999.tb00046.x. PMID  10881389. S2CID  39772232.
  13. ^ Budd, G.E. (2003). "Kambriyen qoldiqlari tarixi va filaning kelib chiqishi". Integrativ va qiyosiy biologiya. 43 (1): 157–165. doi:10.1093 / icb / 43.1.157. PMID  21680420.
  14. ^ a b Buckland, W. (1841). Tabiiy ilohiyotga asoslanib ko'rib chiqiladigan geologiya va mineralogiya. Lea va Blanchard. ISBN  978-1-147-86894-4.
  15. ^ a b Darvin, C (1859). On the Origin of Species by Natural Selection. London: Myurrey. pp.202, 306–308. ISBN  978-1-60206-144-6. OCLC  176630493.
  16. ^ Liñán, E.; Gonzalo, R (2008). "Cryptopalaeontology: Magical descriptions of trilobites about two thousand years before scientific references". In Rábano, I.; Gozalo, R.; García-Bellido, D. (eds.). Advances in Trilobite Research. Madrid: Instituto Geológico y Minero de España. p. 240. ISBN  978-84-7840-759-0.
  17. ^ Bell, Mark (2013). "Fossil Focus: Trilobites". Palaeontology Online. 3 (5): 1–9.
  18. ^ Darwin, Charles R. (1876). The origin of Species by Means of Natural Selection (6 nashr). p. 286.
  19. ^ Uolkott, Kolumbiya (1914). "Cambrian Geology and Paleontology". Smitsonning turli xil to'plamlari. 57: 14.
  20. ^ Holland, Heinrich D (January 3, 1997). "Evidence for life on earth more than 3850 million years ago". Ilm-fan. 275 (5296): 38–9. doi:10.1126/science.275.5296.38. PMID  11536783. S2CID  22731126.
  21. ^ a b v d e f g Cowen, R. (2002). Hayot tarixi. Blackwell Science. ISBN  978-1-4051-1756-2.
  22. ^ Bulut, P.E. (1948). "Evolyutsiyaning ba'zi muammolari va qonuniyatlari, fotoalbom omurgasızlar misolida". Evolyutsiya. 2 (4): 322–350. doi:10.2307/2405523. JSTOR  2405523. PMID  18122310.
  23. ^ Whittington, H. B. (1979). Early arthropods, their appendages and relationships. In M. R. House (Ed.), The origin of major invertebrate groups (pp. 253–268). The Systematics Association Special Volume, 12. London: Academic Press.
  24. ^ a b Uittington, X.B.; Geological Survey of Canada (1985). The Burgess Shale. Yel universiteti matbuoti. ISBN  978-0-660-11901-4. OCLC  15630217.
  25. ^ a b Gould, S.J. (1989). Ajoyib hayot: Burgess slanetsi va tarixning tabiati. W. W. Norton & Company. Bibcode:1989wlbs.book ..... G. ISBN  978-0-393-02705-1. OCLC  185746546.
  26. ^ Bengtson, S. (2004). "Early skeletal fossils" (PDF). In Lipps, J.H.; Vagoner, B.M. (tahr.). Neoproterozoic-Cambrian Biological Revolutions. Paleontologik jamiyat hujjatlari. 10. 67-78 betlar.
  27. ^ a b McNamara, K.J. (20 December 1996). "Dating the Origin of Animals". Ilm-fan. 274 (5295): 1993–1997. Bibcode:1996Sci...274.1993M. doi:10.1126/science.274.5295.1993f. Olingan 2008-06-28.
  28. ^ a b Awramik, S.M. (19 November 1971). "Prekambriyadagi ustunli stromatolit xilma-xilligi: metazoan ko'rinishini aks ettirish". Ilm-fan (mavhum). 174 (4011): 825–827. Bibcode:1971Sci ... 174..825A. doi:10.1126 / science.174.4011.825. PMID  17759393. S2CID  2302113.
  29. ^ a b v Fedonkin, M. A .; Waggoner, B. M. (November 1997). "Kechiktirilgan prekambriyalik qoldiq Kimberella mollyuskka o'xshash bilaterian organizmdir ". Tabiat (mavhum). 388 (6645): 868–871. Bibcode:1997 yil Natura.388..868F. doi:10.1038/42242. ISSN  0372-9311. S2CID  4395089.
  30. ^ masalan. Gehling, James; Jensen, Sören; Droser, Mary; Myrow, Paul; Narbonne, Guy (March 2001). "Burrowing below the basal Cambrian GSSP, Fortune Head, Newfoundland". Geologik jurnal. 138 (2): 213–218. Bibcode:2001GeoM..138..213G. doi:10.1017/S001675680100509X.
  31. ^ Benton MJ; Wills MA; Hitchin R (2000). "Quality of the fossil record through time". Tabiat. 403 (6769): 534–7. Bibcode:2000Natur.403..534B. doi:10.1038/35000558. PMID  10676959. S2CID  4407172.
    Non-technical xulosa Arxivlandi 2007-08-09 da Orqaga qaytish mashinasi
  32. ^ Butterfield, N.J. (2003). "Favqulodda qoldiqlarni saqlash va kembriy portlashi". Integrativ va qiyosiy biologiya. 43 (1): 166–177. doi:10.1093 / icb / 43.1.166. PMID  21680421. Olingan 2008-06-28.
  33. ^ Morris, S.C. (1979). "The Burgess Shale (Middle Cambrian) Fauna". Ekologiya va sistematikaning yillik sharhi. 10 (1): 327–349. doi:10.1146/annurev.es.10.110179.001551.
  34. ^ Yochelson, E.L. (1996). "Discovery, Collection, and Description of the Middle Cambrian Burgess Shale Biota by Charles Doolittle Walcott" [2017-01-11]. Amerika falsafiy jamiyati materiallari. 140 (4): 469–545. JSTOR  987289.
  35. ^ a b v Butterfield, N.J. (2001). Ecology and evolution of Cambrian plankton. The Ecology of the Cambrian Radiation. Columbia University Press, Nyu-York. pp. 200–216. ISBN  978-0-231-10613-9. Olingan 2007-08-19.
  36. ^ Signor, PW .; Lipps, J.H. (1982). "Sampling bias, gradual extinction patterns and catastrophes in the fossil record". In Silver, L.T.; Schulz, P.H. (tahr.). Geological implications of impacts of large asteroids and comets on the earth. Amerika Geologik Jamiyati. 291-296 betlar. ISBN  978-0813721903. A 84–25651 10–42.
  37. ^ "Xitoyning Xubey provinsiyasida katta qazilma topilmalari". BBC yangiliklari. Olingan 24 mart 2019.
  38. ^ "'Mindblowing' haul of fossils over 500m years old unearthed in China". The Guardian. Olingan 24 mart 2019.
  39. ^ Fu, Dongjing; Tong, Guanghui; Dai, Tao M.; Liu, Vey; Yang, Yuning; Zhang, Yuan; Tsyu, Linxao; Li, Lyoyang; Yun, Hao; Vu, Yu; Sun, Ao; Liu, Kong; Pei, Venrui; Gaines, Robert R.; Zhang, Xingliang (2019). "Tsitszyan biotasi - burjist slanets tipidagi toshqotgan toshlar Lagerstätte, Janubiy Xitoyning dastlabki Kambriyenidan". Ilm-fan. 363 (6433): 1338–1342. Bibcode:2019Sci...363.1338F. doi:10.1126 / science.aau8800. PMID  30898931. S2CID  85448914.
  40. ^ "What is paleontology?". Kaliforniya universiteti Paleontologiya muzeyi. Arxivlandi asl nusxasi 2008-09-16. Olingan 2008-09-18.
  41. ^ a b Fedonkin, M.A .; Gehling, J.G.; Kulrang, K .; Narbonne, G.M.; Vickers-Rich, P. (2007). Hayvonlarning ko'payishi: Evolyutsiya va hayvonot olamining diversifikatsiyasi. JHU Press. 213-216-betlar. ISBN  978-0-8018-8679-9. Olingan 2008-11-14.
  42. ^ masalan. Seilacher, A. (1994). "How valid is Cruziana Stratigraphy?". Xalqaro Yer haqidagi jurnal. 83 (4): 752–758. Bibcode:1994GeoRu..83..752S. doi:10.1007/BF00251073. S2CID  129504434.
  43. ^ a b masalan. Knoll, A.H.; Carroll, S.B. (1999-06-25). "Early Animal Evolution: Emerging Views from Comparative Biology and Geology". Ilm-fan. 284 (5423): 2129–37. doi:10.1126/science.284.5423.2129. PMID  10381872. S2CID  8908451.
  44. ^ Amthor, J.E.; Grotzinger, JP .; Schroder, S.; Bowring, S.A .; Ramezani, J .; Martin, M.V .; Matter, A. (2003). "Extinction of Cloudina va Namakalat at the Precambrian-Cambrian boundary in Oman". Geologiya. 31 (5): 431–434. Bibcode:2003Geo....31..431A. doi:10.1130/0091-7613(2003)031<0431:EOCANA>2.0.CO;2. ISSN  0091-7613.
  45. ^ a b v d e f g h Marshall, C. R. (2006). "Explaining the Cambrian "Explosion" of Animals". Annu. Yer sayyorasi. Ilmiy ish. (mavhum). 34: 355–384. Bibcode:2006 NARXALAR..34..355M. doi:10.1146 / annurev.earth.33.031504.103001. S2CID  85623607.
  46. ^ Hug, L.A.; Roger, A.J. (2007 yil avgust). "The Impact of Fossils and Taxon Sampling on Ancient Molecular Dating Analyses" (Bepul to'liq matn). Molekulyar biologiya va evolyutsiya. 24 (8): 889–1897. doi:10.1093/molbev/msm115. ISSN  0737-4038. PMID  17556757.
  47. ^ Peterson, Kevin J.; Butterfield, N.J. (2005). "Origin of the Eumetazoa: Testing ecological predictions of molecular clocks against the Proterozoic fossil record". Milliy fanlar akademiyasi materiallari. 102 (27): 9547–9552. Bibcode:2005PNAS..102.9547P. doi:10.1073/pnas.0503660102. PMC  1172262. PMID  15983372.
  48. ^ Peterson, Kevin J.; Paxta, JA; Gehling, JG; Pisani, D (April 2008). "Bilaterianlarning Ediakaran paydo bo'lishi: genetik va geologik qazilma yozuvlari o'rtasidagi muvofiqlik". Qirollik jamiyatining falsafiy operatsiyalari B: Biologiya fanlari. 363 (1496): 1435–1443. doi:10.1098 / rstb.2007.2233. ISSN  0962-8436. PMC  2614224. PMID  18192191.
  49. ^ a b Craske, A.J.; Jefferies, R.P.S. (1989). "A new mitrate from the Upper Ordovician of Norway, and a new approach to subdividing a plesion" (PDF). Paleontologiya. 32: 69–99. Arxivlandi asl nusxasi (PDF) 2011-08-24. Olingan 2010-12-25.
  50. ^ Valentin, Jeyms V. (2004). Filoning kelib chiqishi to'g'risida. Chikago: Chikago universiteti matbuoti. p. 7. ISBN  978-0-226-84548-7."Classifications of organisms in hierarchical systems were in use by the 17th and 18th centuries. Usually, organisms were grouped according to their morphological similarities as perceived by those early workers, and those groups were then grouped according to their similarities, and so on, to form a hierarchy."
  51. ^ Parker, Andrew (2003). In the blink of an eye: How vision kick-started the big bang of evolution. Sydney: Free Press. 1-4 betlar. ISBN  978-0-7432-5733-6."Evolutionary biologists often make sense of the conflicting diversity of form – not always does a relationship between internal and external parts. Early in the history of the subject, it became obvious that internal organisations were generally more important to the higher classification of animals than are external shapes. The internal organisation puts general restrictions on how an animal can exchange gases, obtain nutrients, and reproduce."
  52. ^ Jefferies, R.P.S. (1979). House, M.R. (ed.). The origin of chordates – a methodological essay. The origin of major invertebrate groups. London: Academic Press. pp. 443–477. sarhisob qilingan Budd, G.E. (2003). "Kambriyen qoldiqlari tarixi va filaning kelib chiqishi". Integrativ va qiyosiy biologiya. 43 (1): 157–165. doi:10.1093 / icb / 43.1.157. PMID  21680420.
  53. ^ Budd, G.E. (1996). "Ning morfologiyasi Opabinia regalis and the reconstruction of the arthropod stem-group". Leteya. 29 (1): 1–14. doi:10.1111 / j.1502-3931.1996.tb01831.x.
  54. ^ Dominguez, P.; Jacobson, A.G.; Jefferies, R.P.S. (Iyun 2002). "Paired gill slits in a fossil with a calcite skeleton". Tabiat. 417 (6891): 841–844. Bibcode:2002Natur.417..841D. doi:10.1038/nature00805. ISSN  0028-0836. PMID  12075349. S2CID  4388653.
  55. ^ a b v d e f Bengtson, S. (2002). "Origins and early evolution of predation". In Kowalewski, M.; Kelley, P.H. (tahr.). The fossil record of predation. The Paleontological Society Papers 8 (Bepul to'liq matn). Paleontologik jamiyat. pp. 289–317. Olingan 2007-12-01.
  56. ^ Stanley (2008). "Predation defeats competition on the seafloor" (ko'chirma). Paleobiologiya. 34 (1): 1–21. doi:10.1666/07026.1. S2CID  83713101.
  57. ^ a b v d e f g Butterfield, N. J. (2007). "Macroevolution and macroecology through deep time" (PDF). Paleontologiya. 50 (1): 41–55. doi:10.1111/j.1475-4983.2006.00613.x.
  58. ^ Condon, D.; Chju, M .; Bowring, S .; Vang, V.; Yang, A.& Jin, Y. (2005 yil 1 aprel). "Neoproterozoy Dushantuo shakllanishidan U-Pb asrlari, Xitoy". Ilm-fan (mavhum). 308 (5718): 95–98. Bibcode:2005Sci ... 308 ... 95C. doi:10.1126 / science.1107765. PMID  15731406. S2CID  11673032.
  59. ^ a b Xiao, S .; Chjan, Y .; Knoll, A. H. (1998 yil yanvar). "Neoproterozoy fosforitida suv o'tlari va hayvon embrionlarining uch o'lchovli saqlanishi". Tabiat. 391 (1): 553–558. Bibcode:1998 yil Natur.391..553X. doi:10.1038/35318. ISSN  0090-9556. S2CID  4350507.
    Xagadorn, Jeyms V.; Syao, Shuxay; Donoghue, Philip C. J.; Bengtson, Stefan; Gostling, Nil J.; va boshq. (2006 yil oktyabr). "Neoproterozoy hayvon embrionlarining hujayra va hujayradan tashqari tuzilishi". Ilm-fan. 314 (5797): 291–294. Bibcode:2006 yil ... 314..291H. doi:10.1126 / science.1133129. ISSN  0036-8075. PMID  17038620. S2CID  25112751.
    Beyli, Jeyk V.; Joy, S. B.; Kalanetra, K. M.; Flood, B. E .; Korsetti, F. A. (2007 yil yanvar). "Neoproterozoy fosforitlaridagi ulkan oltingugurt bakteriyalarining dalillari". Tabiat. 445 (7124): 198–201. Bibcode:2007 yil 4.45..198B. doi:10.1038 / nature05457. ISSN  0028-0836. PMID  17183268. S2CID  4346066.
  60. ^ a b Chen, J. Y .; Bottjer, D. J .; Oliveri, P .; Dornbos, S. Q .; Gao, F.; va boshq. (2004-07-09). "Kembriydan 40 milliondan 55 million yilgacha bo'lgan vaqtgacha bo'lgan kichik Bilateriya qoldiqlari". Ilm-fan. 305 (5681): 218–222. Bibcode:2004 yil ... 305..218C. doi:10.1126 / science.1099213. PMID  15178752. S2CID  1811682.
  61. ^ a b Bengtson, Stefan; Budd, G. (2004). "Izoh Kambriyenga qadar 40 dan 55 million yilgacha bo'lgan bilaterianning kichik qoldiqlari". Ilm-fan. 306 (5700): 1291a. doi:10.1126 / science.1101338. PMID  15550644.
  62. ^ Filipp, C. J .; Nil, J .; Jon, A .; Gostling, Nil J.; Xuldtgren, Tereza; va boshq. (2006 yil avgust). "Sinxrotron rentgenologik tomografik mikroskopiya fotoalbom embrionlari". Tabiat. 442 (7103): 680–3. Bibcode:2006 yil natur.442..680D. doi:10.1038 / nature04890. ISSN  0028-0836. PMID  16900198. S2CID  4411929.
  63. ^ Seilacher, A .; Bose, P.K .; Pflüger, F. (1998). "1 milliard yildan ko'proq vaqt oldin hayvonlar: Hindistondan qazib olingan dalillarni izlash". Ilm-fan (mavhum). 282 (5386): 80–83. Bibcode:1998Sci ... 282 ... 80S. doi:10.1126 / science.282.5386.80. PMID  9756480.
  64. ^ a b Jensen, S. (2003). "Proterozoy va qadimgi kembriy izlari qoldiqlari; naqshlari, muammolari va istiqbollari". Integrativ va qiyosiy biologiya (mavhum). 43 (1): 219–228. doi:10.1093 / icb / 43.1.219. PMID  21680425.
  65. ^ Fedonkin, MA (1992). "Vendian faunalari va Metazoaning dastlabki evolyutsiyasi". Lippsda J.; Signor, P. W. (tahrir). Metazoa paydo bo'lishi va dastlabki evolyutsiyasi. Nyu-York: Springer. 87-129 betlar. ISBN  978-0-306-44067-0. OCLC  231467647. Olingan 2007-03-08.
  66. ^ Dzik, J (2007), "Verdun sindromi: himoya zirhlari va infaunal boshpanalarning bir vaqtning o'zida kelib chiqishi prekambriyen-kembriy o'tish davrida", Vikers-Rich, Patrisiya; Komarower, Patrisiya (tahr.), Ediakaran biotasining ko'tarilishi va qulashi, Maxsus nashrlar, 286, London: Geologiya jamiyati, 405–414-betlar, doi:10.1144 / SP286.30, ISBN  9781862392335, OCLC  156823511CS1 maint: mualliflar parametridan foydalanadi (havola)
  67. ^ a b Seilacher, Adolf; Luis A. Buatoisb; M. Gabriela Mangano (2005-10-07). "Ediakaran-Kembriya o'tishidagi qoldiqlarning izlari: Xulq-atvorni diversifikatsiya qilish, ekologik aylanish va atrof-muhit o'zgarishi". Paleogeografiya, paleoklimatologiya, paleoekologiya. 227 (4): 323–356. Bibcode:2005PPP ... 227..323S. doi:10.1016 / j.palaeo.2005.06.003.
  68. ^ Dastlabki global isish kutilmaganda kichik hayot shakllarining portlashi natijasida yuzaga kelgan - teskari
  69. ^ Shen, B .; Dong, L .; Xiao, S .; Kovalevski, M. (2008 yil yanvar). "Avalon portlashi: Ediakara morfosmik fazasining rivojlanishi". Ilm-fan (mavhum). 319 (5859): 81–84. Bibcode:2008 yil ... 319 ... 81S. doi:10.1126 / science.1150279. PMID  18174439. S2CID  206509488.
  70. ^ Grajdankin (2004). "Ediakaran biotalarida tarqalish naqshlari: biogeografiya va evolyutsiyaga qarshi fatsiyalar". Paleobiologiya. 30 (2): 203–221. doi:10.1666 / 0094-8373 (2004) 030 <0203: PODITE> 2.0.CO; 2. ISSN  0094-8373.
  71. ^ a b Ervin, DH (iyun 1999). "Bodiplanlarning kelib chiqishi" (bepul to'liq matn). Amerika zoologi. 39 (3): 617–629. doi:10.1093 / icb / 39.3.617.
  72. ^ Seilacher, A. (1992). "Vendobionta va Psammocorallia: prekembriy evolyutsiyasining yo'qolgan konstruktsiyalari". Geologiya jamiyati jurnali, London (mavhum). 149 (4): 607–613. Bibcode:1992JGSoc.149..607S. doi:10.1144 / gsjgs.149.4.0607. S2CID  128681462. Olingan 2007-06-21.
  73. ^ a b Martin, M.V .; Grajdankin, D.V .; Bowring, S.A .; Evans, D.A.D .; Fedonkin, M.A .; Kirschvink, JL (2000-05-05). "Neoproterozoyik Bilaterian tanasi va izlari qoldiqlari asri, Oq dengiz, Rossiya: Metazoan evolyutsiyasi uchun ta'siri". Ilm-fan (mavhum). 288 (5467): 841–845. Bibcode:2000Sci ... 288..841M. doi:10.1126 / science.288.5467.841. PMID  10797002.
  74. ^ Mooi, R .; Bruno, D. (1999). "G'alati filum ichidagi evolyutsiya: birinchi echinodermalarning homologiyalari" (PDF). Amerika zoologi. 38 (6): 965–974. doi:10.1093 / icb / 38.6.965.
  75. ^ McMenamin, MA (2003). "Spriggina trilobitoid ekdysozoan ". Dasturlar bilan referatlar (mavhum). 35 (6): 105.
  76. ^ Lin, J. P .; Gon, S. M.; Gehling, J. G.; Babkok, L. E.; Chjao, Y. L .; Chjan, X. L .; Xu, S. X .; Yuan, J. L .; Yu, M. Y .; Peng, J. (2006). "A Parvancorina- Janubiy Xitoyning Kembriyasidan kelgan artropodga o'xshaydi. Tarixiy biologiya. 18 (1): 33–45. doi:10.1080/08912960500508689. S2CID  85821717.
  77. ^ a b v Butterfild, NJ (2006 yil dekabr). "Ba'zi guruhli" qurtlarni "bog'lash: burjess slanetsidagi toshqotgan lofotroxozoanlar". BioEssays. 28 (12): 1161–6. doi:10.1002 / bies.20507. ISSN  0265-9247. PMID  17120226. S2CID  29130876.
  78. ^ "Scientific American" 2014 yil aprel
  79. ^ Li, C .; Chen, J. Y .; Hua, T. E. (1998). "Uyali tuzilishga ega bo'lgan prekambriyalik gubkalar". Ilm-fan. 279 (5352): 879–882. Bibcode:1998 yil ... 279..879L. doi:10.1126 / science.279.5352.879. PMID  9452391.
  80. ^ Yin, L .; Xiao, S .; Yuan, X. (2001). "Guychjou provintsiyasining Vengan shahridagi Doushantuo fosforitlaridan spikulaga o'xshash tuzilmalar bo'yicha yangi kuzatuvlar". Xitoy fanlari byulleteni. 46 (21): 1828–1832. Bibcode:2001 yil ChSBu..46.1828Y. doi:10.1007 / BF02900561. S2CID  140612813.
  81. ^ Gnilovskaya, M. B. (1996). "Rossiya platformasining Vendianidan yangi saarinidlar". Dokl. Ross. Akad. Nauk. 348: 89–93.
  82. ^ Fedonkin, M. A. (2003). "Metazoa kelib chiqishi proterozoy davridagi qoldiq qoldiqlari asosida" (PDF). Paleontologik tadqiqotlar. 7 (1): 9–41. doi:10.2517 / prpsj.7.9. S2CID  55178329. Arxivlandi asl nusxasi (PDF) 2009-02-26. Olingan 2009-11-16.
  83. ^ Andrey Yu. Juravlev; va boshq. (Sentyabr 2009). "Muammoli Ediakaran qoldiqlarining dastlabki topilmalari Gaojiashoniya Sibirda va uning kelib chiqishi ". Geologik jurnal. 146 (5): 775–780. Bibcode:2009 yil GeoM..146..775Z. doi:10.1017 / S0016756809990185.
  84. ^ Hofmann, H.J .; Mountjoy, EW (2001). "Namakalat-Klodina Neoproterozoic Miette Group (Byng Formation), Britaniya Kolumbiyasida yig'ilish: Kanadadagi eng qadimgi qobiq qoldiqlari ". Geologiya. 29 (12): 1091–1094. Bibcode:2001 yil Geo .... 29.1091H. doi:10.1130 / 0091-7613 (2001) 029 <1091: NCAINM> 2.0.CO; 2. ISSN  0091-7613.
  85. ^ a b Grotzinger, JP .; Vatters, V.A .; Knoll, AH (2000). "Proterozoic Nama Group, Namibiya terminalining trombolit-stromatolit riflaridagi kaltsiylangan metazoanlar". Paleobiologiya. 26 (3): 334–359. doi:10.1666 / 0094-8373 (2000) 026 <0334: CMITSR> 2.0.CO; 2. ISSN  0094-8373.
  86. ^ Xua, X.; Chen, Z .; Yuan X.; Chjan, L .; Xiao, S. (2005). "Eng qadimgi biomineralizatsiya qilinadigan hayvonlarda skeletogenez va jinssiz ko'payish Cloudina". Geologiya. 33 (4): 277–280. Bibcode:2005 yil Geo .... 33..277H. doi:10.1130 / G21198.1.
  87. ^ Miller, A.J. (2004). "Cloudinaning ekologik va filogenetik oqibatlari bilan qayta ko'rib chiqilgan morfologiyasi" (PDF). Olingan 2007-04-24.
  88. ^ Xua, X.; Pratt, B.R .; Chjan, L.U.Y.I. (2003). "Cloudina chig'anoqlaridagi burg'ulashlar: Neoproterozoy terminalidagi murakkab yirtqich-o'lja dinamikasi". PALAY. 18 (4–5): 454–459. Bibcode:2003 yil Palay..18..454H. doi:10.1669 / 0883-1351 (2003) 018 <0454: BICSCP> 2.0.CO; 2. ISSN  0883-1351.
  89. ^ Shtayner, M .; Li, G.; Qian, Y .; Chju, M .; Erdtmann, B. D. (2007). "Neoproterozoyik davrdan Kambriyadagi mayda toshqotgan tosh birikmalar va Yangtze Platformasining qayta ko'rib chiqilgan biostratigrafik korrelyatsiyasi (Xitoy)". Paleogeografiya, paleoklimatologiya, paleoekologiya. 254 (1–2): 67–99. Bibcode:2007PPP ... 254 ... 67S. doi:10.1016 / j.palaeo.2007.03.046.
  90. ^ Rozanov AY, Khomentovskiy V.V., Shabanov YY, Karlova GA, Varlamov AI, Luchinina VA, Pegel 'TV, Demidenko YE, Parkxayev PY, Korovnikov IV, Skorlotova NA va boshq. (2008). "Quyi kembriyning bosqichga bo'linishi muammosiga". Stratigrafiya va geologik korrelyatsiya. 16 (1): 1–19. Bibcode:2008SGC .... 16 .... 1R. doi:10.1007 / s11506-008-1001-3. S2CID  128128572.
  91. ^ V. V. Xmentovskiy; G. A. Karlova (2005). "Tommotian sahna bazasi Kembriyning pastki chegarasi sifatida Sibirda". Stratigrafiya va geologik korrelyatsiya. 13 (1): 21-34. Arxivlandi asl nusxasi 2011-07-14. Olingan 2010-06-04.
  92. ^ V. V. Xmentovskiy; G. A. Karlova (2002). "Sibirning Nemakit-Doldinyan va Tommotian bosqichlari o'rtasidagi chegara (Vendian-Kembriy tizimlari)". Stratigrafiya va geologik korrelyatsiya. 10 (3): 13–34.
  93. ^ Kembriyalik taroqli jellarda skeletizatsiya tarixi yo'qolgan - Science Advances
  94. ^ Maluof, A. C .; Porter, S. M.; Mur, J. L .; Dudas, F. O .; Bowring, S. A .; Xiggins, J. A .; Fike, D. A .; Eddi, M. P. (2010). "Hayvonlar va okeanning geokimyoviy o'zgarishlari to'g'risida birinchi Kembriy yozuvlari". Geologiya jamiyati Amerika byulleteni. 122 (11–12): 1731–1774. Bibcode:2010GSAB..122.1731M. doi:10.1130 / B30346.1.
  95. ^ Ivantsov, A. Y. (2009). "Yangi tiklanish Kimberella, Muammoli Vendian Metazoan ". Paleontologik jurnal. 43 (6): 601–611. doi:10.1134 / S003103010906001X. S2CID  85676210.
  96. ^ Porter, S. (2011). "Yirtqichlarning ko'payishi". Geologiya. 39 (6): 607–608. Bibcode:2011Geo .... 39..607P. doi:10.1130 / focus062011.1.
  97. ^ Koen, P. A .; Schopf, J. W.; Butterfild, N. J .; Kudryavtsev, A. B.; MacDonald, F. A. (2011). "Neoproterozoy protistlarining o'rtalarida fosfat biomineralizatsiyasi". Geologiya. 39 (6): 539–542. Bibcode:2011 yilGeo .... 39..539C. doi:10.1130 / G31833.1.
  98. ^ Kennedi, M. J .; Droser, M. L. (2011). "Fluvial muhitdagi dastlabki kembriy metazoanlar, dengizdan tashqari kembriy nurlanishining dalili". Geologiya. 39 (6): 583–586. Bibcode:2011Geo .... 39..583K. doi:10.1130 / G32002.1.
  99. ^ Metyus, SS; Missarzhevskiy, V.V. (1975-06-01). "Kekembriyaning oxiri va Kembriyaning dastlabki davridagi kichik qobiq qoldiqlari: so'nggi ishlarga obzor". Geologiya jamiyati jurnali. 131 (3): 289–303. Bibcode:1975JGSoc.131..289M. doi:10.1144 / gsjgs.131.3.0289. S2CID  140660306.
  100. ^ Liberman, BS (1999 yil 1 mart). "Kembriya radiatsiyasining Darviniy merosini trilobit filogeniyasi va biogeografiyasi yordamida sinovdan o'tkazish". Paleontologiya jurnali (mavhum). 73 (2): 176. doi:10.1017 / S0022336000027700.
  101. ^ Dornbos, S.Q .; Bottjer, D.J. (2000). "Eng qadimgi echinodermalarning evolyutsion paleoekologiyasi: Helikoplakoidlar va Kembriya substrat inqilobi". Geologiya. 28 (9): 839–842. Bibcode:2000Geo .... 28..839D. doi:10.1130 / 0091-7613 (2000) 28 <839: EPOTEE> 2.0.CO; 2. ISSN  0091-7613.
  102. ^ Butterfild, Nikolas J. (2003). "Favqulodda qoldiqlarni saqlash va kembriy portlashi". Integrativ va qiyosiy biologiya. 43 (1): 166–177. doi:10.1093 / icb / 43.1.166. PMID  21680421.
  103. ^ Konvey Morris, Simon (2008). "Kamdan-kam uchraydigan xordat, Metaspriggina Uolkotti Simonetta va Insom, Burgess Slanetsidan (O'rta Kembriya), Britaniya Kolumbiyasi, Kanada". Paleontologiya jurnali. 82 (2): 424–430. doi:10.1666/06-130.1. S2CID  85619898.
  104. ^ Syao, Shuxay; Shtayner, M; Knol, A. H; Knoll, Endryu H. (2002). "Janubiy Xitoyda neoproterozoyik Miaohe uglerodli biotani qayta baholash". Paleontologiya jurnali. 76 (2): 345–374. doi:10.1666 / 0022-3360 (2002) 076 <0347: MCCIAT> 2.0.CO; 2. ISSN  0022-3360.
  105. ^ a b v Xarvi, TX; Butterfild, NJ (2008 yil aprel). "Katta Kembriyadagi qisqichbaqasimon zarrachalarning murakkab oziqlanishi". Tabiat. 452 (7189): 868–71. Bibcode:2008 yil natur.452..868H. doi:10.1038 / nature06724. ISSN  0028-0836. PMID  18337723. S2CID  4373816.
  106. ^ Xarvi, T.P.H. (2007). "Kembriya pankrustatsiyasining ekologiyasi va filogeniyasi" (PDF). Buddda G.E .; Streng, M .; Deyli, A.C .; Willman, S. (tahrir). Tezislar bilan dastur. Paleontologik uyushmaning yillik yig'ilishi. 51. Uppsala, Shvetsiya.
  107. ^ a b Droser, Meri L; Finnegan, Set (2003). "Ordovik radiatsiyasi: Kembriya portlashining davomi?". Integrativ va qiyosiy biologiya. 43 (1): 178–184. doi:10.1093 / icb / 43.1.178. PMID  21680422.
  108. ^ Budd, Grem (2013). "Hayvonlarning kelib chiqishi: inqilobiy kambriyen qoldiqlari". Hozirgi Genomika. 14 (6): 344–354. doi:10.2174/13892029113149990011. PMC  3861885. PMID  24396267.
  109. ^ Ervin, D. X .; Laflamme, M.; Tvidt, S. M.; Sperling, E. A .; Pisani, D .; Peterson, K. J. (2011). "Kembriyning jumboqli holati: hayvonlarning dastlabki tarixidagi dastlabki divergensiya va keyinchalik ekologik muvaffaqiyat". Ilm-fan. 334 (6059): 1091–1097. Bibcode:2011 yil ... 334.1091E. doi:10.1126 / science.1206375. PMID  22116879. S2CID  7737847.
  110. ^ Kouchinskiy, A .; Bengtson, S .; Runnegar, B. N .; Skovsted, C. B.; Shtayner, M .; Vendrasko, J. J. (2012). "Erta Kembriya biomineralizatsiyasi xronologiyasi". Geologik jurnal. 149 (2): 221–251. Bibcode:2012 yil GeoM..149..221K. doi:10.1017 / s0016756811000720.
  111. ^ Paterson, Jon R.; Edgekombe, Gregori D.; Li, Maykl S. Y. (2019). "Trilobit evolyutsiyasi sur'atlari Kembriya portlashining davomiyligini cheklaydi". Milliy fanlar akademiyasi materiallari. 116 (10): 4394–4399. Bibcode:2019PNAS..116.4394P. doi:10.1073 / pnas.1819366116. PMC  6410820. PMID  30782836.
  112. ^ Landing, E .; Kouchinsky, A. V. (2016). "Kembriy evolyutsion nurlanishining o'zaro bog'liqligi: geoxronologiya, eng qadimgi Kambriyen (Terreneyviya) mayda chig'anoq qoldiqlari (SSF) taksilarining evolyutsion stazi va xronostratigrafik ahamiyati". Geol. Mag. 153 (4): 750–756. Bibcode:2016GeoM..153..750L. doi:10.1017 / s0016756815001089.
  113. ^ a b Budd, G.E .; Jekson, I.S.C. (2016). "Kembriyadagi ekologik yangiliklar va toj guruhi filasining kelib chiqishi". Fil. Trans. R. Soc. B. 371 (1685): 20150287. doi:10.1098 / rstb.2015.0287. PMC  4685591. PMID  26598735.
  114. ^ Syao, Shuxay; Yuan, Xunlay; Knoll, Endryu H. (2000-12-05). "Terminal proterozoy fosforitlaridagi evetazoan qoldiqlari?". Amerika Qo'shma Shtatlari Milliy Fanlar Akademiyasi materiallari. 97 (25): 13684–13689. Bibcode:2000PNAS ... 9713684X. doi:10.1073 / pnas.250491697. PMC  17636. PMID  11095754.
  115. ^ Yin, Zongjun; Chju, Maoyan; Devidson, Erik X.; Bottjer, Devid J.; Chjao, Fangxen; Tafforeau, Pol (2015-03-24). "Kambriyenga qadar 60 Myr bo'lgan uyali rezolyutsiyaga ega gubka tanasi qoldiqlari". Amerika Qo'shma Shtatlari Milliy Fanlar Akademiyasi materiallari. 112 (12): E1453-E1460. Bibcode:2015PNAS..112E1453Y. doi:10.1073 / pnas.1414577112. ISSN  0027-8424. PMC  4378401. PMID  25775601.
  116. ^ Teylor, P.D .; Berning, B .; Uilson, MA (2013). "Kambriyalik" bryozoan "ning qayta talqini Pywackia sakkizinchi sifatida ". Paleontologiya jurnali. 87 (6): 984–990. doi:10.1666/13-029. S2CID  129113026.
  117. ^ a b v Ervin, D.H .; Devidson, E.H. (2002 yil 1-iyul). "Oxirgi umumiy bilateriya ajdodi". Rivojlanish. 129 (13): 3021–3032. PMID  12070079. Olingan 2008-07-10.
  118. ^ Bengtson, S .; Zhao, Y. (1992 yil 17-iyul). "Kechgacha prekambriyen minerallashgan ekzoskeletlardagi yirtqich quduqlar". Ilm-fan. 257 (5068): 367–9. Bibcode:1992 yil ... 257..367B. doi:10.1126 / science.257.5068.367. PMID  17832833. S2CID  6710335.
  119. ^ Chen, J.Y .; Oliveri, P .; Devidson, E .; Bottjer, D.J. (2004). Kambriyenga qadar 40 milliondan 55 million yilgacha bo'lgan vaqt oralig'idagi kichik Bilateriya qoldiqlari "izohiga javob""". Ilm-fan. 306 (5700): 1291. doi:10.1126 / science.1102328.
  120. ^ Liberman, B. (2003). "Kembriya nurlanishining zarbasini olish". Integrativ va qiyosiy biologiya. 43 (1): 229–237. doi:10.1093 / icb / 43.1.229. PMID  21680426.
  121. ^ Jeykobs, D. K .; Ray, C. G.; Vedin, C. J .; Kostriken, R .; Desalle, R .; Staton, J. L .; Geyts, R.D .; Lindberg, D. R. (2000). "Mollyuska gravürlü ifoda, ketma-ket tashkil qilish va qobiq evolyutsiyasi". Evolyutsiya va rivojlanish. 2 (6): 340–347. doi:10.1046 / j.1525-142x.2000.00077.x. PMID  11256378. S2CID  25274057.
  122. ^ Ervin, DH (2007). "Tafovut: morfologik naqsh va rivojlanish konteksti". Paleontologiya. 50 (1): 57–73. doi:10.1111 / j.1475-4983.2006.00614.x.
  123. ^ Stokmeyer Lofgren, Andrea; Plotnik, Roy E.; Vagner, Piter J. (2003). "Karbonifer artropodlarning morfologik xilma-xilligi va fanerozoy orqali nomutanosiblik namunalari to'g'risida tushunchalar". Paleobiologiya. 29 (3): 349–368. doi:10.1666 / 0094-8373 (2003) 029 <0349: MDOCAA> 2.0.CO; 2. ISSN  0094-8373.
  124. ^ Ervin, D. H. (2011). "Evolyutsion uniformitarizm". Rivojlanish biologiyasi. 357 (1): 27–34. doi:10.1016 / j.ydbio.2011.01.020. PMID  21276788.
  125. ^ Mounce, R. C. P.; Wills, M. A. (2011). "Filogenetik holati Diania da'vo qildi " (PDF). Tabiat. 476 (E1): E1, munozarasi E3-4. Bibcode:2011 yil 476E ... 1M. doi:10.1038 / tabiat10266. PMID  21833044. S2CID  4417903.
  126. ^ McMenamin, M. (2010). "Garri Blekmor Uittington 1916–2010". Geoscientist. 20 (11): 5. Arxivlangan asl nusxasi 2012-08-03 da. Olingan 2011-08-12.
  127. ^ Budd, G. E .; Mann, R. P. (2018). "Tarixni g'oliblar yozgan: o'tmish surishining fotoalbomlarga ta'siri" (PDF). Evolyutsiya. 72 (11): 2276–229. doi:10.1111 / evo.13593. PMC  6282550. PMID  30257040.
  128. ^ Shirmeyster, B.E .; deVos, JM; Antonelli, A .; Bagherri, XC (2013). "Ko'p hujayralilik evolyutsiyasi siyanobakteriyalarning ko'payishi va Buyuk Oksidlanish hodisasiga to'g'ri keldi". PNAS. 110 (5): 1791–1796. Bibcode:2013PNAS..110.1791S. doi:10.1073 / pnas.1209927110. PMC  3562814. PMID  23319632.
  129. ^ a b Kanfild, D.E .; Poulton, SS; Narbonne, G.M. (2007). "Kech-neoproterozoyik chuqur okean oksigenatsiyasi va hayvonlar hayotining ko'tarilishi". Ilm-fan. 315 (5808): 92–5. Bibcode:2007Sci ... 315 ... 92C. doi:10.1126 / science.1135013. PMID  17158290. S2CID  24761414.
  130. ^ Bekker, A .; Gollandiya, XD .; Vang, P.I .; Rumble, III, D .; Stein, H.J .; Xanna, JL .; Koetzi, L.L .; Beukes, HJ (2003). "Atmosfera kislorodining ko'tarilish sanasi". Tabiat. 427 (6970): 117–120. Bibcode:2004 yil natur.427..117B. doi:10.1038 / tabiat02260. PMID  14712267. S2CID  4329872.
  131. ^ a b v Parfrey, L.V.; Lam, D.J.G .; Knol, A.H .; Katz, LA (2011). "Multigenali molekulyar soatlar bilan erta ökaryotik diversifikatsiya vaqtini baholash". PNAS. 108 (33): 13624–13629. Bibcode:2011PNAS..10813624P. doi:10.1073 / pnas.1110633108. PMC  3158185. PMID  21810989.
  132. ^ Tou, K.M. (1970-04-01). "Kislorod-kollagen ustuvorligi va metazoaning dastlabki fotoalbomlari". Milliy fanlar akademiyasi materiallari (mavhum). 65 (4): 781–788. Bibcode:1970 PNAS ... 65..781T. doi:10.1073 / pnas.65.4.781. PMC  282983. PMID  5266150.
  133. ^ Ketling, DC; Glin, KR; Zahnle, KJ; McKay, CP (iyun 2005). "Nega O2 Yashash mumkin bo'lgan sayyoralardagi murakkab hayot va sayyoralarning "Oksigenlanish vaqti tushunchasi talab qiladi"". Astrobiologiya. 5 (3): 415–438. Bibcode:2005 yil AsBio ... 5..415C. doi:10.1089 / ast.2005.5.415. ISSN  1531-1074. PMID  15941384.
  134. ^ Butterfild, N. J. (2009). "Kislorod, hayvonlar va okean shamollatish: muqobil ko'rinish" Geobiologiya. 7 (1): 1–7. doi:10.1111 / j.1472-4669.2009.00188.x. PMID  19200141.
  135. ^ Kiz, Bob. "Ozon". www.albany.edu. Albani universiteti. Olingan 22 noyabr 2014.
  136. ^ Xofman, P.F.; Kaufman, A.J .; Halverson, G.P. & Schrag, D.P. (1998 yil 28-avgust). "Neoproterozoy qorli er". Ilm-fan (mavhum). 281 (5381): 1342–1346. Bibcode:1998 yil ... 281.1342H. doi:10.1126 / science.281.5381.1342. PMID  9721097.
  137. ^ Hayotning portlashi uchun roman evolyutsion nazariyasi
  138. ^ Piters, S. E .; Geynes, R. R. (2012). "Kambriyen portlashining qo'zg'atuvchisi sifatida" Buyuk nomuvofiqlikni "shakllantirish". Tabiat. 484 (7394): 363–366. Bibcode:2012 yil natur.484..363P. doi:10.1038 / nature10969. PMID  22517163. S2CID  4423007.
  139. ^ Skvayr, R. J .; Kempbell, I. H .; Allen, C. M .; Uilson, J. J. (2006). "Transgondwanan Supermountain Yerdagi hayvonlarning portlovchi nurlanishini qo'zg'atdimi?" (PDF). Yer va sayyora fanlari xatlari. 250 (1): 116–133. Bibcode:2006E & PSL.250..116S. doi:10.1016 / j.epsl.2006.07.032. Olingan 11 sentyabr 2017.
  140. ^ de Roza, R.; Grenier, J.K .; Andreeva, T .; Kuk, CE .; Adoutte, A .; Akam M.; Kerol, SB .; Balavoine, G. (iyun 1999). "Brakiyopodlar va priapulidlardagi xoks genlari va protostom evolyutsiyasi". Tabiat. 399 (6738): 772–6. Bibcode:1999 yil natur.399..772D. doi:10.1038/21631. ISSN  0028-0836. PMID  10391241. S2CID  4413694.
  141. ^ Nyuman, S.A .; Bhat, R. (2008 yil aprel). "Dinamik naqsh modullari: morfologik rivojlanish va evolyutsiyaning fizik-genetik determinantlari". Jismoniy biologiya. 5 (1): 0150580. Bibcode:2008 PHBio ... 5a5008N. doi:10.1088/1478-3975/5/1/015008. ISSN  1478-3967. PMID  18403826.
  142. ^ Jekson, Daniel J.; Makis, Lusiana; Reytner, Yoaxim; Wörheide, Gert (2011 yil 12-avgust). "Genlarning gorizontal ravishda uzatilishi metazoanning erta biomineralizatsiya strategiyasining evolyutsiyasini qo'llab-quvvatladi". BMC evolyutsion biologiyasi. 11: 238. doi:10.1186/1471-2148-11-238. PMC  3163562. PMID  21838889.
  143. ^ Asta-sekin ko'tarilish emas, balki kislorodning haddan tashqari tebranishlari Kembriya portlashiga sabab bo'ldimi?
  144. ^ Kembriya portlashi ko'pligi emas, balki kislorod etishmasligi tufayli yuzaga kelgan
  145. ^ Erta okean anoksiyasi birinchi marta ommaviy qirilib ketish hodisasiga olib kelgan bo'lishi mumkin | Ilm | Vaterloo universiteti
  146. ^ Parker, Endryu (2003). Ko'z ochib yumguncha. Kembrij, Massachusets: Persey kitoblari. ISBN  978-0-7382-0607-3. OCLC  52074044.
  147. ^ Makkol (2006). "Vendian (Ediakaran) geologik yozuvlarda: geologiyaning Kambriyadagi portlash oldidagi jumboqlari". Earth-Science sharhlari. 77 (1): 1–229. Bibcode:2006ESRv ... 77 .... 1M. doi:10.1016 / j.earscirev.2005.08.004.
  148. ^ Dokkins, R .; Krebs, R.J. (1979 yil 21 sentyabr). "Turlar orasida va ichida qurollanish musobaqalari". Qirollik jamiyati materiallari B. 205 (1161): 489–511. Bibcode:1979RSPSB.205..489D. doi:10.1098 / rspb.1979.0081. JSTOR  77442. PMID  42057. S2CID  9695900.
  149. ^ McMenamin, M. A. S. (1988). "Paleokologik teskari aloqa va vendian-kembriy o'tish". Ekologiya va evolyutsiya tendentsiyalari. 3 (8): 205–208. doi:10.1016/0169-5347(88)90008-0. PMID  21227202.
  150. ^ Chjan, Z.; Xolmer, L. E.; Robson, S. P.; Xu, S .; Vang X.; Vang, H. (2011). "Kembriyaning dastlabki lingulati brakiyopodlarida saqlanib qolgan pedikulalari bilan durofagin qobig'ining shikastlanganligi to'g'risida birinchi yozuv". Paleogeografiya, paleoklimatologiya, paleoekologiya. 302 (3–4): 206–212. Bibcode:2011PPP ... 302..206Z. doi:10.1016 / j.palaeo.2011.01.010.
  151. ^ a b Lopes-Villalta, Xulian Simon (2016). "Kambriyen-Ordovikiya nurlanishi uchun yirtqich-diversifikatsiya gipotezasini sinovdan o'tkazish". Paleontologik tadqiqotlar. 20 (4): 312–321. doi:10.2517 / 2016PR022. ISSN  1342-8144. S2CID  131794128.
  152. ^ Peterson, K.J .; McPeek, MA va Evans, D.A. (Iyun 2005). "Hayvonlarning dastlabki evolyutsiyasining tempasi va rejimi: toshlar, xoks va molekulyar soatlar haqida xulosalar". Paleobiologiya (mavhum). 31 (2 (qo'shimcha)): 36-55. doi:10.1666 / 0094-8373 (2005) 031 [0036: TAMOEA] 2.0.CO; 2. ISSN  0094-8373.
  153. ^ Ervin, D. X .; Tvid, S. (2011). "Metazoa Ediakaran-Kembriya diversifikatsiyasining ekologik haydovchilari". Evolyutsion ekologiya. 26 (2): 417–433. doi:10.1007 / s10682-011-9505-7. S2CID  7277610.
  154. ^ Solé, R.V .; Fernández, P. & Kauffman, SA (2003). "Morfogenezning gen tarmog'i modelida adaptiv yurishlar: Kembriya portlashi haqidagi tushunchalar". Int. J. Dev. Biol. 47 (7): 685–693. arXiv:q-bio / 0311013. Bibcode:2003q.bio .... 11013S. PMID  14756344.
  155. ^ a b Sperling, E.A .; Frider, K.A .; Raman, A.V .; Girguis, P.R .; Levin, L.A .; Knoll, AH (2013). "Kislorod, ekologiya va hayvonlarning kembriy nurlanishi". PNAS. 110 (33): 13446–13451. Bibcode:2013PNAS..11013446S. doi:10.1073 / pnas.1312778110. PMC  3746845. PMID  23898193.
  156. ^ Ervin, D.H .; Valentin, JV .; Sepkoski, J.J. (1987 yil noyabr). "Diversifikatsiya hodisalarini qiyosiy o'rganish: mezeozoyga qarshi erta paleozoy davri". Evolyutsiya. 41 (6): 1177–1186. doi:10.2307/2409086. JSTOR  2409086. PMID  11542112.
  157. ^ Valentin, JV (1995 yil aprel). "Kembriyadan keyin nima uchun yangi phyla yo'q? Genom va ekokosmik gipotezalar qayta ko'rib chiqildi". PALAY (mavhum). 10 (2): 190–194. Bibcode:1995 yil Palay..10..190V. doi:10.2307/3515182. JSTOR  3515182.

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