In biology and ecology, extinction is the end of an organism or of a group of organisms (taxon), normally a species. The moment of extinction is generally considered to be the death of the last individual of the group (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.
Examples of extinct animals : Javan Tiger, Thylacine, Dodo, Passenger Pigeon, Caribbean Monk Seal, Steller's Sea Cow, Aurochs, Elephant Bird, Woolly Mammoth, Dusky Seaside Sparrow
ENDANGERED
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters.
Examples of endangered animals : Dhole, Blue Whale, Asian Elephant, Giant Panda, Snow Leopard, African Wild Dog, Green Sea Turtle, Malayan Tapir,Tiger, Steller's Sea Lion, Philippine Eagle, Markhor, Bornean Orangutan, Grevy's Zebra, Tasmanian Devil
