HIST-1107EL Study Guide - Quiz Guide: Radiolaria, Foraminifera, Speciation
5 Dec 2020
School
Department
Course
Professor
Document Summary
History of life: around 600ma of history is missing in the rock record, the earliest rocks are the. Acasta gneiss which is 4. 1ga: the cenozoic era began 65ma, permian, triassic, jurassic, cretaceous, the precambrian represents the first 4ga of the earth"s history, taphonomy is the study of fossilisation. Radiolaria, diatoms and some sponges (demosponges and hexactinellids) have siliceous skeletons. Analogous characteristics have more than one evolutionary origin: changes that occurred in jumps of steps is punctuated equilibrium. Allopatric speciation is where species become isolated and evolve separately. The oldest stromatolites are 3. 5ga: bif represent the earliest significant levels of atmospheric oxygen. Fe2+ is soluble and dissolved, when oxygen levels rose the iron in the oceans oxidised to form fe3+ which is insoluble and sank. The more different the genome, the further back in time the divergence was: benthic animals live on the seafloor.
