Extinction has always been a part of our world. Dinosaurs became extinct, so did woolly mammoths. The rate of extinction has increased too fast. In the past 300 years, about 100 kinds of mammals have become extinct. Right now hundreds of birds, mammals, reptiles, amphibians , and fish are endangered, as well as more than 25,000 plants.
Human activity is largely responsible for today's wildlife crisis.
Laws try to protect endangered species. This endangered Bali mynah was one of several birds illegally smuggled into the United States. Fortunately, these birds were given to the San Diego Zoo where they have reproduced. Their offspring have been released back into their wild habitat where they are now reproducing. With more than six billion people living on Earth, wild habitats are constantly shrinking as human occupation expands into once wild places.