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Outlook is grim for mammals and birds as human population grows, study says

The ongoing global growth in the human population will inevitably crowd out mammals and birds and has the potential to threaten hundreds of species with extinction within 40 years, new research shows.

Biology - Ecology

3 hours ago

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Surprise species at risk from climate change

(Phys.org) —Most species at greatest risk from climate change are not currently conservation priorities, according to an International Union for Conservation of Nature (IUCN) study that has introduced a ...

Biology - Ecology

7 hours ago

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Putting flesh on the bones of ancient fish: Synchrotron X-rays reconstruct soft tissue on 380 million year old fish

Swedish, Australian and French researchers present for the first time miraculously preserved musculature of 380 million year old armoured fish discovered in north-west Australia. This research will help scientists ...

Other Sciences - Archaeology & Fossils

Jun 13, 2013

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30-year woodland trial underway at Monarto

A pioneering long-term University of Adelaide experiment to see how best to restore overgrazed land back to native woodland gets underway at Monarto Zoo today.

Biology - Ecology

Jun 13, 2013

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Fossil kangaroo teeth reveal mosaic of Pliocene ecosystems in Queensland

The teeth of a kangaroo and other extinct marsupials reveal that southeastern Queensland 2.5-5-million-years ago was a mosaic of tropical forests, wetlands and grasslands and much less arid than previously thought. The chemical ...

Other Sciences - Archaeology & Fossils

Jun 12, 2013

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Extinction

In biology and ecology, extinction is the end of a species or group of taxa. The moment of extinction is generally considered to be the death of the last individual of that species (although the capacity to breed and recover may have been lost before this point). Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "re-appears" (typically in the fossil record) after a period of apparent absence.

Through evolution, new species arise through the process of speciation—where new varieties of organisms arise and thrive when they are able to find and exploit an ecological niche—and species become extinct when they are no longer able to survive in changing conditions or against superior competition. A typical species becomes extinct within 10 million years of its first appearance, although some species, called living fossils, survive virtually unchanged for hundreds of millions of years. Extinction, though, is usually a natural phenomenon; it is estimated that 99.9% of all species that have ever lived are now extinct.

Prior to the dispersion of humans across the earth, extinction generally occurred at a continuous low rate, mass extinctions being relatively rare events. Starting approximately 100,000 years ago, and coinciding with an increase in the numbers and range of humans, species extinctions have increased to a rate unprecedented since the Cretaceous–Tertiary extinction event. This is known as the Holocene extinction event and is at least the sixth such extinction event. Some experts have estimated that up to half of presently existing species may become extinct by 2100.

This text uses material from Wikipedia, licensed under CC BY-SA

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