科学家发现古代南极青蛙

species -- n. biology : a group of animals or plants that are similar and can produce young animals or plants : a group of related animals or plants that is smaller than a genus

amphibian – n. an animal (such as a frog or toad) that can live both on land and in water

ecosystem -- n. everything that exists in a particular environment

global -- adj. involving the entire world

extinct – adj. no longer existing

relative -- n. something that belongs to the same group as something else because of shared characteristics, qualities, etc.