Asirai na duniya - zamanin Cambrian

Kamar yadda na aikin kimiyya, asalin rayuwa a wannan duniyar tamu for game da uku biliyan shekaru da suka wuce a cikin nau'i na sauki kwayoyin - ware microscopic sandunansu, filamentary Tsarin, mai siffar zobe kuma polygonal-celled algae. Wadannan kwayoyin iya zama kawai a cikin ruwa da kuma kawai a dumi canjin yanayin.

A general, to sun tsira sosai 'yan burbushin daga Precambrian lokaci. Juyin Halitta alama stalled tun kafuwar rayuwa a kan uku shekaru biliyan, canza da kuma kammala da kawai data kasance jinsunan algae da microscopic kwayoyin.

Duk da haka, 580 miliyan shekaru da suka wuce, a wani sauyi a tarihin juyin halitta - zamanin Cambrian. Its duration ne a cikin rãyuwar duniya ne kananan - 80 shekaru miliyan. A sa'an nan da ba zato ba tsammani, kuma kusan lokaci guda akwai ban mamaki iri-iri na invertebrate jinsunan. More muhimmanci - rayayyun kwayoyin halitta a cikin wani gajeren lokaci sun iya saya da wani m calcareous kwarangwal.

Mahara nazarin halittu siffofin da Cambrian ya riga daga dukan nau'i na rayuwa ta zamani, ciki har da mutane. Wannan shi ne daya-lokaci aukuwa da kuma kaifi bambancin da jinsunan da aka sani da zamanin cambrian.

Land a lokacin da aka mai cikakkar pustnynyu, duk rayuwa da aka mayar da hankali kawai a cikin ruwa. Nahiyoyi na duniya yana da wani gaba ɗaya daban-daban location: misali, a shafin na Greenland da kuma Arewacin Amirka ne, a nahiyar Lavrentsov kudu ya Brazil ɓangaren duniya. Arabia, Afirka da kuma Madagascar sun united nahiyar Afrika, dake a cikin arewa na Rasha ɓangaren duniya, rabu da mashigar zurfin Siberian da babban yankin kasar Sin. A kudu, akwai wata katuwar Australian ɓangaren duniya, wanda daga baya ya karya up cikin India, Australia da kuma yawan tsibiran.

A zamanin Cambrian fito da wasu zamani dutsen: Northern Appalachian Mountains, da Sayan Ridge Mountains Chingiztau (Kazakhstan).

A cikin ruwa, hanzari blossomed rai: ya zaunar da trilobites, radiolarians, Sponges, brachiopods. Bayyana archeocyathids - kwayar dabbobi, wanda shi ne mai giciye tsakanin murjãni da Sponges. Su massively lazimta kasa na ruwa jikinsu, kafa irin na murjani reefs. By karshen zamanin Cambrian, sai suka zama dadaddun.

A wannan lokaci, musamman trilobites wadãta - m arthropod kamar zamani woodlice. Suna da wani lebur faifai-dimbin yawa jiki da chitinous makamai, zuwa kashi 45-50 segments da wani jam'i na kafafu.

Zuwa ga ƙarshen zamanin Cambrian akwai farko sulke vertabrate kifi prototypes.

Saboda haka, ba tare da wani tsaka-tsakin yanayi da kuma matsakaici nauyin jinsunan kwayoyin da protozoa a duniya ba zato ba tsammani kafa da yawa invertebrate da vertebrate jinsunan, prototypes na zamani siffofin. A zamanin Cambrian ne cryptic juyin Jump a cikin tarihin duniya.

A mafi yawan lokuta masu bincike a sakamakon wannan sauyi aukuwa m jari na oxygen a cikin iska a cikin teku, kazalika da kara yankin Flushing salts na sushi da kuma kara yawa na alli da magnesium a cikin ruwa. A sunadarai abun da ke ciki na ruwa ya canza sosai cewa kwayoyin da suke zaune a can, samu mai yawa dama ga canji da kuma samuwar nau'in.

Ko bayar da shawarar cewa a game da wannan lokaci, da Duniya ya sanya kwatsam juyin mulki kusan 90 digiri, wanda shi ne dalilin da ya sa akwai ban mamaki motsi na duk nahiyoyi, tectonic canjawa da kuma samuwar na zamani taimako na duniya ta surface. Yana kuma ya rinjayi samuwar sabon nau'in da adaptations rayuwa.

A lokaci na Duniya ta juyin halitta ya gana da yawa na bala'i haka ne, kusan lokaci guda kuma ba tare da togiya dinosaur bace miliyan 65 da suka wuce. Kuma a cikin Permian zamanin a cikin wani gajeren lokaci a lokaci guda ya zama dadaddun kusan 95% na marine rayuwa - shi ne 245 da miliyan da suka wuce.

Amma a cikin dukan wadannan asirai kawai zamanin Cambrian bambanta ta m, maimakon halakar da jinsunan. Abokan adawar juyin m gani a cikin wuyar warwarewa da zamanin cambrian tabbaci na allahntaka asalin zamani siffofin rayuwa, ciki har da mutane.