Metazoans-Life Grows Up fer the Seowbell Earth event, oxygm was freely available
ID: 253570 • Letter: M
Question
Metazoans-Life Grows Up fer the Seowbell Earth event, oxygm was freely available for the The fossils have been preserved b process call first time, increasing the po-ifor ideforms become higter plaagbatizatio--in atom-by-mom mplacemmt of th, original more differentiated. The stage was set foer malticellelar lise maerial by phosphate. The preservation is extraordinary, it goes wss ln this lecture, we'll look at the evidence we have for melticellolar down to the very cellular level. The fossils are thought to incdea reaturos and why and how creatares increased in sizn. We'll theorine aboutvarlety of creatures:Sossilieed algae, acritechs, eaweeds, sponges lw nature of the irst broad animal ecoxystem and what would bring an and primitive corals. Some sciencists suspect some of these structures beliong to the bilateria Blarians represent abroad grouping within arimals that includes why did animals evolve to langer formz? Evolution does not happen · * without a purpose: There must be an advantage to growng largreverything that is mot a member of the caidaria fcoral, jellyfish Atter all, being small had been a successful strategy The majy onges). If the fossils are indeed biateria, this is soeve of the ofthe biosphere's mass was stillmicrosc compared to creatures earliest evidence we have that diversilation wihin animals had that lived on the surface of the plaset occurred long before the Phanerooie eon. Larger sine permitsacreatare to physically ineract with itsefore the Doushantuo discoveries, envircnment. For example, amoebas can move around a bi, but inlmals Alexander Marray, a Scotish general, they are at the meecy of water curents. Larger creatures are mach more in control of their own destiny and can physically Nostrngnphy, lke fossils are used to coerelate betwoen areas we had earlier evidence of called Aspidella to correlate the rocks of Newfoundland. In Ose of the firnt paleoetologists of the Geolegical Sarvey of A larger ereature can aso differentiate in specialized functions Cnada, Elkanah Billings, suggested that Aspidela oould be from perform more complex activities. These specialized functions period below the Cambrian that is, the Procambeian the creature's ability to exploit varied opportunities and scientife community rejected that theory because the existence of Precambrian fossils was considered impossible. In fact, in some enhance its chances of passing on its genes to the next generation scientific circles, al the rocks below the Cambrian were called Amic, meaning"without life-as pposed to Phare use. damaged .Oygen levels had risen from 1 percent to about 10 percent of Finally, multicellular creatures ? replace their components. They are not reliant oa just one unit The story then moves to Australia, where Reginald C . current levels by the end of the last Snowball Earth, agound 635 miningologist exploring the Ediacara Hilis in southerm Australia w some interesting stractures on the million years ago. This rising oxygen level was associsted with Because he was in Precambrian rocks, he was somewhat surprised he development of something very important: O, or onone. Ozone to find a rich fauna full of strange disk-like creatures, some of which It would take discoveries in the Unined Kingdom to convince the Because Britain was widely mapped geologically by that time, the fossils are hamed Charnia masoni Charnia for the Charnwood pert of what is called the Ediacaran fauna. It has been found in which blocks ultraviolet radiation and shields the shallower water, where there are many food resources levels of oxygen to form collagen. Collagen, a net of proteins, is the . existed. In 1957 Another beneist of oxygen is that animals need relatively highscieastie ommunity that Precambrian fossils Roer Mason discovered such a scaffolding that animals use to build bigger bodies According to Darwinian evolution, there should be a chain of odks these fossils came from were clearly Procambrian. These be a chsin of ane fossil record back to some sort of simple common ancestor. But. Wrow have evidence of Precambrian fama Crna nano appearance of large creatures was so sudden and dramatic that 30 localities on five difßferent continents and comprises ateas the Cambrian, that is called the Phanerozoic. This word means These are not just isolated creatures; they represent a increasingly more primitive creatures going back into prehistoryForest and masoni for the discoverer. in Darwin's time, no such fossils had beem found; in fact, the early geologists started a new group of periods, beginning wdh 100 species morphologically diverse assemblage of life. They appear about 580 million years ago, but they are largely gone by the base of the Cambrian period, at about 542 million years ago. Those early ancestors have now been found. The tiny fossils, less than 0.03 inches in diameter, are from the Doushantuo formation of southern China and date to 635 to 551 million years ago. The.The last part of the Precambrian that immediately precedes the sediments in the Doushantuo formation were deposited in a seriesCambrian period is now named for these fauna: the Ediacaran of legoons that developed as sea levels rose following claciation. period. Most Ediacarans lived in fairly well-lit shallew waters, but some earlier forms may not have been photosynthetic and probably nhabied slighrly deeper, dimmer waters
Explanation / Answer
Oxygen
Differentiated
10
Physical interact
Collagen
Oxygen
Ozone, O3
Bilateral
China
Lagoons
rose
Precambrian
Ediacaran
Five
Late Precambrian
Kimberella
Animal
Vendozoa
Phanerozoic