Extinction is a process in which all individuals of a species die out, leaving only a countable number of individuals in captivity or none.
Sometimes extinction occurs naturally (such as the dinussaur etintion) but currently, humans have been causing the extintion of many species (such as the tasmanian tiger extintion).
The extinction of a species can result in the extinction of many other species which depended on the extinct one in some way. That is the most common result but some species do manage to adapt.
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