Plenty of species have been observed eating their own young. Still other species see their young competing for resources, so only the strongest survive.
Collectively, the world's last 20 Christmas Island pipistrelle bats ( Pipistrellus murrayi ) weigh less than a fifth of a pound (around 60 grams). That's not much mass for any species – let alone one on the razor's edge of extinction.
The rabbit-like American pika ( Ochotona princeps ) got lucky this week. The U.S. Fish & Wildlife Service, responding to a lawsuit filed by the Center for Biological Diversity and Earthjustice, has agreed to assess whether the increasingly rare animal qualifies for protection under the Endangered Species Act.
Biologists report in the Proceedings of the National Academy of Sciences this week that they were unable to find a pair of previously common Guatemalan salamander species -- Pseudoeurycea brunnata and Pseudoeurycea goebeli -- and say they are apparently extinct.
Coral reefs are dying off at record rates, thanks to pollution, disease and global warming. Scientists worldwide are trying to come up with new ideas to conserve and protect not just the coral reefs, but also the biodiversity and human economies that depend upon them for their survival.
Few species have come as close to extinction as the milu ( Elaphurus davidianus ) and survived. For centuries, the rare Chinese animal, also known as Père David's deer, has existed only in captivity.
The last Pyrenean ibex (Capra pyrenaica pyrenaica) died nine years ago, the victim of loneliness (and a falling tree). But for a brief, seven-minute window, the extinct species may have recently been resurrected, thanks to cloning.
It may be the end of the road for an endangered species of rabbit. After eight years and several million dollars, federal officials will likely halt a program by the end of this year designed to save the Columbia basin pygmy rabbit from extinction, according to the Associated Press.
Yesterday was Groundhog Day, but what about Prairie Dog Day?
The prairie dog—the "groundhog of the West"—could use a little attention these days.
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