Mass extinctions history

See S. M. Stanley, Extinction, Scientific American Library, Freeman, New York, 1987. This short book provides a useful and informed discussion of the history of mass extinctions of living species. 

Fossil molecules and past natural product diversity Fossil remains as old as 3,000 My have been found of the precursors of modem cyanobacteria. The oldest remains of eukaryotes date to 2,500 My. Thus, together with many other landmark findings, the history of fossil remains is illustrative of the past events, in particular mass extinctions, which are dramatic episodes of biodiversity loss from unusual causes. 

Much of tile theorizing pertaining to mass extinctions of flora and fauna during the past history of the earth has been based upon finding... 

Permian Period The last geologic time period of the Paleozoic Era, noted for the greatest mass extinction in earth history, when nearly 96% of species died out. 

About 250 million years ago, 90% of life on earth was destroyed in some sort of cataclysmic event. This event, which ended the Permian period and began the Triassic (the P-T boundary), is the most devastating mass extinction in the earth s history— far surpassing the catastrophe 65 million years ago that wiped out the dinosaurs (the K-T boundary). 

CourtiUot V., Jaeger 1.1., Yang Z. Z., Feraud G., and Hofmann C. K. B. (1996) The influence of continental flood basalts on mass extinctions where do we stand In The Cretaceous-Tertiary Event and Other Catastrophes in Earth History, Geological Society of America Special Paper 307 (eds. G. Ryder, D. Fastovsky, and S. Gartner), pp. 513-525. 

Leary P. N. and Rampino M. R. (1990) A multicausal model of mass extinctions increase in trace metals in the oceans. In Extinction Events in Earth History, Lecture Notes in Earth Science, 30 (eds. E. G. Kauffman and O. H. WaUiser). Springer, Berlin, pp. 45—55. 

Sepkoski J. J. (1986) Phanerozoic overview of mass extinction. In Pattern and Processes in the History of Life (eds. D. Raup and D. Japlonski). Springer-Verlag, pp. 277-295. 

Vickery A. M. and Melosh H. J. (1990) Atmospheric erosion and impactor retention in large impacts with application to mass extinctions. In Global Catastrophes in Earth History, Geological Society of America Special Paper 247 (eds. V. L. Sharpton and P. D. Ward). Geological Society of America, Boulder, Co, pp. 289-300. 

Knoll A. H., Bambach R. K., Canfield D. E., and Grotzinger J. P. (1996) Comparative Earth history and Late Permian mass extinction. Science 273, 452-457. 

Major catastrophes that lead to mass extinction of species occurred five times in Earth s history during the last 540 million years the last one was 65 million years back (end of the Mesozoic) when the dinosaurs disappeared. The high rate at which species are disappearing has led scientists to suggest that the sixth mass extinction is already under way Barnosky estimates that in 330years, 75% of mammalian species will be extinct (Barnosky et al., 2011). 

This is true for biology as well as history. Chemistry predicts what type of species will survive, but it only places odds on whether a particular species will survive. Also, complex systems are more fragile than simple ones. The Cambrian Explosion led to periodic mass extinctions. Life walks the line between order and chaos. Complex systems fall off that line more easUy. 

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