Endangered Species
Several years ago, scientists estimated that over 1.5 million species of animals and plants exist on earth. More recent estimates have increased that number to about 30 million. However, pollution, deforestation, and exploitation of animals and plants now threaten many species. In the U.S. alone, over 700 species of plants, and almost 500 species of animals, are listed as threatened or endangered, and are in danger of dying out.
The National Wildlife Federation places animal and plant species that are in danger of dying out into three categories. A vulnerable species is in danger because its’ numbers are low or declining. The Mexican long-tongued bat and the lowland leopard frog are examples of vulnerable species. A threatened species is in danger because its habitat is in trouble. If the problem is not solved, this species will become endangered. The eastern indigo snake and the red kangaroo are examples of threatened species. An endangered species is in immediate danger of dying out completely, or becoming extinct. Its’ numbers are low and it needs protection in order to survive. There are more than 1,00 endangered animal species worldwide; the Siberian tiger and the now leopard are two examples. The National Wildlife Federation also has a category for species that are extinct, or no longer living. Dinosaurs are probable the most famous example of un extinct species.
There are many factors that can cause an animal or plant species to become endangered. The main cause of species endangerment is humanity’s destruction of both aquatic and terrestrial habitats. Deforestation and soil, air, and water pollution can all destroy a habitat. This can then cause a large number of animals or plants to die. Another cause of endangerment is exploitation of animals. Uncontrolled hunting of whales in the last century, for example, caused many whale species to become endangered. A third cause of endangerment is the demand for animas parts for use in certain foods or medicines.
Introducing a non-native species to an environment can also cause species endangerment. A native species is one that develops naturally in a particular geographic area, and has done so for a long time. A non-native species might be introduced into a new environment by humans, either intentionally or by accident. Other natural causes, such as changes in the weather, can also introduce an exotic species to a new environment. This exotic species may not be able to live with the native species, and the result may be the destruction of the native species or its natural habitat.
Many people do not worry greatly about species endangerment. However, it is important to remember that many life-saving medicines are created from certain plants or animals. The purple foxglove plant is, for example, the main source of the drug digitalis. Without this drug, over 3 million people n the U.S. would die every year within seventy-two hours of suffering a heart attack. To ensure that we have a long-term supply of digitalis well into the future, we must make sure that the purple foxglove and its habitat do not become endangered or extinct.
Societies such as the World Wildlife Fund, and the National Wildlife Federation, try to raise awareness of threatened animals and plants. These organizations work with government agencies to save and decrease the numbers of threatened or endangered species, and to make new laws that will protect these species. Many of these plans work, but some do not. Public awareness of this issue is important. To reserve the quality of our lives, and the lives of future generations, we must also protect plant and animal species now, and in the future.