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About 17% of all families, 50% of all genera [6] and 75% of all species became extinct. [2] In the seas all the ammonites, plesiosaurs and mosasaurs disappeared and the percentage of sessile animals was reduced to about 33%. All non-avian dinosaurs became extinct during that time. [20]
As long as species have been evolving, species have been going extinct. It is estimated that over 99.9% of all species that ever lived are extinct. The average lifespan of a species is 1–10 million years, [35] although this varies widely between taxa. A variety of causes can contribute directly or indirectly to the extinction of a species or ...
It does not represent all marine species, just those that are readily fossilized. The labels of the traditional "Big Five" extinction events and the more recently recognised Capitanian mass extinction event are clickable links; see Extinction event for more details. (source and image info)
Some reasons these species go extinct are from habitat loss, overharvesting, pollution, invasive species, and climate change. Invertebrates make up most of Earth's biodiversity which is why they do not go extinct as fast as other species. Marine Invertebrates: These species' average lifespan is 5–10 million years.
More than 99 percent of all species that ever lived (over five billion) [1] are estimated to be extinct. [ 2 ] [ 3 ] Estimates on the number of Earth's current species range from 10 million to 14 million, [ 4 ] with about 1.2 million or 14% documented, the rest not yet described . [ 5 ]
This page features lists of species and organisms that have become extinct. The reasons for extinction range from natural occurrences, such as shifts in the Earth's ecosystem or natural disasters, to human influences on nature by the overuse of natural resources, hunting and destruction of natural habitats.
Estimates of species lost per year vary widely—from 1.5 to 40,000 species—but all indicate that human activity is driving this crisis. [69] In The Future of Life (2002), biologist Edward Osborne Wilson predicted that, if current trend continues, half of Earth's higher lifeforms could be extinct by 2100. More recent studies further support ...
Another study, published in 2011 by PLoS Biology, estimated there to be 8.7 million ± 1.3 million eukaryotic species on Earth. [11] Some 250,000 valid fossil species have been described, but this is believed to be a small proportion of all species that have ever lived. [12] Global biodiversity is affected by extinction and speciation.