The painting, by G. The pool in the foreground represents a hydrothermal vent with mineral deposits around its rim. Similar vents may have incubated the origin of life on Earth. The yellow mounds in the larger water body are stromatolites. Plate Tectonic Reconstruction Over the four billion years of the Precambrian the Earth's surface features changed vastly. Meteorites Most meteorites were formed within about million years of the formation of the solar system.
Precambrian Rocks and Minerals One of the great stories of the Precambrian is the evolution of an oxygen atmosphere. Precambrian Microbial Life The earliest evidence of life comes from chemical fossils formed only million years after the end of the Hadean period of intense bombardment by meteorites and planetesimals 3.
Multicellular Animals - the Ediacaran Fauna Multicellular animals first become significant life-forms, leaving the earliest clear fossil evidence, at the beginning of the Vendian, about 0. Nearly all of the specimens on display were provided as gifts to the museum courtesy of the individuals listed below: Don Garlick, HSU Geology Dept.
Jere H. Lipps, University of California Museum of Paleontology, arranged for the casts of Ediacaran life from specimens provided by M. Associated Exhibit :. Bibliography Knowledge about the precambrian has changed rapidly in recent years. Fedonkin, Mikhail A. The Johns Hopkins Press, Baltimore Andrew H. Princeton University Press, Princeton Schopf, J. William Schopf, ed.
Jones and Bartlett Publishers, Boston. Runnegar, Bruce "Evolution of the Earliest Animals. Richard A. Des Marais, David J. Halliday, Alex N. Holland, Heinrich D. Kramers, Jan. Lipps, Jere H. Plenum Press, New York. Martin, M. Grazhdankin, S. Autotrophs and soft-bodied heterotrophs filled the continental shelf regions around Rodinia.
Many were Cnidarians similar to small jellyfish with radial body symmetry and specialized cells to sting prey and convey it into the body cavity. Fossils show that significantly different populations inhabited different localities. Some scientists classify them as being related to the mollusks. The boundary between the Ediacaran Period of the Proterozoic Era and the Cambrian Period of the Paleozoic Era is not as clear-cut as it was once thought to be.
It used to be thought that increasing oxygenation caused a mass extinction of Ediacaran forms and a geologically sudden proliferation of new complex forms. Now it is understood that there were many complex multicellular animals capable of living in the higher oxygen of the Ediacaran environment.
However they were nearly all soft-bodied forms, which left few fossil traces behind for us to find. Paid Content How Hong Kong protects its sea sanctuaries. History Magazine These 3,year-old giants watched over the cemeteries of Sardinia. Magazine How one image captures 21 hours of a volcanic eruption.
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See how people have imagined life on Mars through history. See More. The end of the Precambrian Time marked the start of the more quickly progressing evolution of species over Geologic Time. Actively scan device characteristics for identification.
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