Permian extinction

Nick Lane has pubhshed a detailed picture of the Permian extinction see Nature 448 122 (2007). He estimates that this extinction killed off up to 96% of all species then alive. 

Huey RB, Ward PD (2005) Hypoxia, Global warming, and terrestrial Late Permian extinctions. Science 308 398-401... 

During the Permian extinction, the oceans warmed to 104°F. Volcanic gases reacted with and depleted the protective ozone layer. As a result, 70% of the species on the land and 96% of the species in the sea vanished. A reef gap appears in the fossil record because the reefs were destroyed. Elements from previous chapters were injected into this chapter, including nickel, which supported methanogens with... 

But perhaps 5 million years after the storm had passed, life began to recover. New reefs formed, different from the previous species but stUl recognizably reefy. After the Permian extinction, complex communities survived better and outnumbered simpler communities three to one, when before the extinction they had been about equal in number. Twenty million years after the extinction, dinosaurs and giant amphibians prohferated to fill the Earth. 

A full-genome analysis of 48 different birds dates a huge burst of evolutionary innovation at 60-65 million years ago, immediately after the impact 66 million years ago, This has been described as an evolutionary Big Bang. Before the impact, we had the ancestors of ostriches. Five million years later, we had distinct ancestors of penguins, owls, cuckoos, doves, and falcons. We may owe the existence of birds to the absence of the dinosaurs. When dinosaurs vacated, birds filled in the space. (Insects may have had their own Big Bang right after the Permian extinction.)... 

Permian extinction The third and largest of the five great extinctions, also known as the Permian-Triassic (P-Tr), which occurred about 250 million years ago. 

The early Mesozoic has recently received much attention with respect to the recovery of marine life from the greatest ever (end-Permian) extinction event and another major extinction event at the end of the Triassic (overviews in Erwin, 2006 Smith, 2007 and references therein). The Permian/Triassic Boundary (PTB) in particular may play a pivotal role in assessing putative cause-and-effect scenarios during the Palaeozoic-Mesozoic transition (Algeoetal., 2007). However, fish species— normally... 

Mutter, R.J. and Neuman, A.G. (2009) Reeoveiy from the end-Permian extinction event Evidence from LilUput Listracanthus . Palaeogeography, Palaeoclimatology, Palaeoecology, 284 22-28. 

Permian 290 Myr All land united in one large continent - Pangaea large glaciers form. Reptiles, including mammal-like forms, radiate amphibians decline diverse orders of insects evolve. Conifers appear. Mass extinction at end of period (ca. 95% of all species disappear)... 

If the asteroid-impact theory is correct, the extinctions should be repetitive and the Ir anomaly should be observed in other geological stratigraphic levels corresponding to known extinctions. About five other massive extinctions (besides the one at the end of the Cretaceous Period) have been noted [25]. These come at the end of the Cambrian ( 500 MY ago), the Ordovician (M35 MY age), the Devonian ( 345 MY ago), the Permian ( 230 MY ago) and the Triassic ( 195 MY ago) Periods. 

Wignall PB, Twitchett RJ (1996) Oceanic anoxia and the end Permian mass extinction. Science 272 1155-1158... 

Section 8.6.2, the Permian period ended with the largest mass extinction event that has yet occurred on planet Earth. As the ocean began a sustained recovery at the beginning of the Mesozoic era, opportunities likely abounded for the survivors to take over empty ecological niches through evolutionary adaptation. Prior to the advent of planktonic... 

The first large mass mortality occurred during the end-Ordovician, 440 My ago (Fig. 16.1). A less extensive loss took place during the late Devonian, followed by the huge mass mortality of the end-Permian, 250 My ago, when the trilobites - marine arthropods that had survived the late Ordovician event - disappeared. Coming after a period of dry cold climate that saw the Appalachian mountains buUd up, the end-Permian mass mortality brought to extinction more than half the families of living species. It paved the way to the scleractinians, which formed the coral reefs (Stanley 2001). 

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). 

Figure 1 Phanerozoic carbon isotope record. Mass extinction intervals are shaded in gray (widths do not correspond to durations of inserts) (a) global marine carbonate record (after Veizer et al, 1999) (b) marine carbonate record from the Late Ordovician of the Baltic States (after Brenchley et al, 1994) (c) Late Devonian marine organic carbon record from New York State (after Murphy et al, 2000) (d) Late Permian marine carbonate record from China (after Bowring etal, 1998) (e) Late Triassic marine organic carbon record from Canada (after Ward etal, 2001) (f)Late Cretaceous-early Tertiary record of the carbon isotopic difference between fine fraction and benthic carbonate (left panel), between shallow dwelling planktonic and benthic foraminifera (open symbols, right panel) and between more deeper dwelling planktonic and benthic foraminifera (filled symbols, right panel) from the south Atlantic...

The largest extinction event of the Phanerozoic occurred in the latest Permian, a time when both shallow and deep marine environments appear to have experienced widespread anoxia. As a result, anoxia has figured prominently into proposed extinction mechanisms for this time, although models for extinction that invoke multiple causality are currently in favor (e.g., Erwin, 1993, 1995 Kozur, 1998). 

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. 

Wang K., Geldsetzer H. H. J., and Krouse H. R. (1994) Permian-Triassic extinction. Organic delta-C-13 evidence from British-Columbia, Canada. Geology 22, 580-584. 

Wignall P. B. and Hallam A. (1992) Anoxia as a cause of the Permian/Triassic mass extinction, facies evidence from Northern Italy and the western United States. Palaeogeogr. Palaeoclimat. Palaeoecol. 93, 21-46. 

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