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Background extinction rates are typically measured in order to give a specific classification to a species and this is obtained over a certain period of time. There are three different ways to calculate background extinction rate. [5] The first is simply the number of species that normally go extinct over a given period of time.
A model by Foote (2007) found that many geological stages had artificially inflated extinction rates due to Signor-Lipps "backsmearing" from later stages with extinction events. [65] Estimated extinction rates among genera through time. From Foote (2007), top, and Kocsis et al. (2019), bottom
End-Capitanian extinction event: 260 Ma: Volcanism from the Emeishan Traps, [28] resulting in global cooling and other effects Olson's Extinction: 270 Ma Unknown. [29] [30] [31] Possibly a change in climate, but evidence for this is weak. [32] This event may actually be a slow decline over 20 Ma. [33] Carboniferous: Carboniferous rainforest ...
This is much faster than the expected “background” extinction rate, or the rate at which species would naturally die off without outside influence — in the absence of human beings, these 73 ...
More significantly, the current rate of global species extinctions is estimated as 100 to 1,000 times "background" rates (the average extinction rates in the evolutionary time scale of planet Earth), [71] [72] faster than at any other time in human history, [73] [74] while future rates are likely 10,000 times higher. [72]
The following list is incomplete by necessity, since the majority of extinctions are thought to be undocumented, and for many others there isn't a definitive, widely accepted last, or most recent record. According to the species-area theory, the present rate of extinction may be up to 140,000 species per year. [1]
It was the most severe extinction event of the past 500 million years, wiping out 80% to 90% of species on land and in the sea. Mystery deepens over cause of Earth's worst mass extinction event ...
The Late Pleistocene saw the extinction of many mammals weighing more than 40 kilograms (88 lb), including around 80% of mammals over 1 tonne. The proportion of megafauna extinctions is progressively larger the further the human migratory distance from Africa, with the highest extinction rates in Australia, and North and South America. [11]