"Eastern cougars that once roamed North America from Canada to South Carolina are extinct and no longer warrant federal Endangered Species Act protections, US wildlife managers have said."

"Conservationists decried a proposal on Monday by U.S. wildlife and marine animal managers to tweak rules tied to the federal Endangered Species Act, saying the plans would place "crippling" impediments to citizens petitioning to save imperiled creatures."

"Biologists looking at 40 years of fisheries data from Puget Sound have documented a dramatic shift in marine species. Key fish in the food chain, like herring and smelt, have declined, while the number of jellyfish has increased exponentially, to the detriment of the marine ecosystem."

"Climate change could drive up to a sixth of animals and plants on Earth to extinction unless governments cut rising greenhouse gas emissions, according to a U.S. study published on Thursday."

"U.S. fisheries managers on Monday proposed lifting protections for most humpback whales around the globe, including in American waters, based on evidence the mammals have made a strong comeback since commercial whaling drove them near extinction."

"Ocean acidification triggered by massive volcanic eruptions helped cause the worst mass extinction in the history of life on Earth, according to a new study."

"Scientists believe the dwindling axolotl, or Mexican salamander, holds secrets of aging and regeneration"