Endangered and Extinct Animals

Dinosaurs are the most famous extinct animals.

The most famous extinct animals are the dinosaurs. Paleontologists study dinosaur fossils, movies bring them back to life, and their likenesses are sold as action figures.

Not all animals became extinct millions of years ago. In the modern world, animals continue to disappear from the Earth; other animals are in danger of disappearing. The article "Extinct and Endangered Animals" reports that "extinct species outnumber living ones by a factor of perhaps a thousand to one."

What Does Extinct Mean?

Dodo birds are extinct.

Webster's Third New International Dictionary defines extinction as "no longer living... that has died out all together." Extinction occurs when an entire species dies out. The dodo bird, the Steller's sea cow and the Tasmanian wolf are examples of species that are now extinct.

In the past, cataclysmic natural events caused the mass extinction of species. Today, however, the impact of humans are causing animal species to become endangered.

What Does Endangered Mean?

The American alligator is an endangered species.

The U.S. Endangered Species Act was enacted by Congress to prevent the extinction of threatened species of animals, fish and plants. Two categories exist under the act: endangered and threatened. The act defines an endangered species as "... one that is in danger of extinction throughout all or a significant portion of its range." A threatened species is "... one that is likely to become endangered in the foreseeable future throughout all or a significant portion of its range."

What Is the Endangered Species List?

The black-footed ferret is an endangered species.

The U.S. Fish and Wildlife Service manages the list of endangered species. Once an animal is added to the list, it is protected by the Endangered Species Act. This means that the protected species cannot be hunted or harmed in any way. In some cases, prohibitions may be placed on the development of the habitat of that particular species.

Once a species has recovered its population, it's no longer considered endangered and is removed from the endangered species list.

What Causes Extinction?

Habitats are being destroyed.

The U.S. Fish and Wildlife Service website states, "Scientists estimate that the natural extinction rate is approximately 1 species lost in every 100 years. Yet, more than 500 species in North America have disappeared in less than 400 years."

Humans are destroying animal habitats for farms or housing developments. Pollution of air, water and land is disrupting important ecosystems. Fishermen have overfished; animals such as tigers and elephants have been overhunted.

Ecosystems

A healthy ecosystem is interlinked with all parts of the natural world.

The U.S. Fish & Wildlife Service writes, "An ecosystem is a web of living and nonliving parts that is connected and maintained by energy from the sun and nutrient flow." This means that every part of the natural world---the air, the soil, the water, the animals, the plants---is interlinked and dependent upon each other. The loss of one species can cause the collapse of an entire ecosystem.

References

• Animal Port: Extinct and Endangered Animals
• Oxford University Museum of Natural History: Extinct and Endangered
• U.S. Fish & Wildlife Service: Listing a Species as Threatened or Endangered
• U.S. Fish & Wildlife Service: Endangered Means There Is Still Time

Resources

• 50 Birds: Information and Pictures of Extinct Animals