Some have populations numbering less than five individuals.
Connecting protected areas and allowing tigers the corridors they need to roam could help rescue currently bottle-necked populations.
The restaurant has previously offered tacos filled with python, alligator, elk, kangaroo, rattlesnake and other animals.
Around 250 million years ago, over 90 percent of all marine species on Earth went extinct.
Exxon, Shell, Gazprom, BP and Rosneft are together planning an oil rig off the coast of Russia -- a move that could harm an already critically endangered whale species.
Toxic waters could have even been the norm through much of the planet's history.
Did "fright" really mysteriously kill thousands of blackbirds?
A biodiversity crisis as a result of invasive species may have capped the Devonian - not a mass extinction event.
Food found stuck between their teeth reveals that Neanderthals enjoyed cereals and other carbs.
Mam-mothers kept their woolly babies close to the hip.