Besides human interference, species endangerment and extinction can happen without human interference. Extinction is a natural part of evolution. Fossil records show that long before people came along. Factors such as over specialization, competition, sudden climatic change, and catastropic events like volcanic eruptions and earthquakes drove the decline of numerous species.

    There are a few warning signs that a species could become extinct. If a species has some economic importance, such as the Atlantic salmon, it maybe at risk. Surprisingly, large predator, who we might expect to have an adventage over other species, are often at risk as well. This list includes grizzly bears, bald eagles, and gray wolves.

    A species whose gestational period is lengthy, or who have small numbers of spring at each birth has the potential to become endangered more readily. The mountain gorilla and California condor are two examples. And species with weak genetic make-up, like Manatees or giant pandas, have more risk of extinction with each generation.

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