Dinosaurs have been extinct for about 65 million years but nobody knows the exact cause for them becoming extinct. Also, although they are said to be extinct there are some people who believe that there are some birds who have evolved from dinosaurs. The difference between dinosaurs and later animals becoming extinct and endangered are humans had nothing to do with human extinction. Some theories that scientists believe to be the reasons of why dinosaurs became extinct are volcano eruptions and diseases. The two theories that scientists believe have more effect on the extinction of dinosaurs are asteroids and climate changes.
http://www2.scholastic.com/browse/article.jsp?id=4754
Woolly Mammoth:
The Woolly Mammoth a well known animal came to life about 1.8 million years ago. But, unfortunately about 10,000 years ago Woolly Mammoth’s became extinct. Although Woolly Mammoth’s were mainly extinct because of nature, unlike dinosaurs humans also had a small effect on Woolly Mammoth’s extinction. Humans would over hunt Woolly Mammoth’s which was a reason they became extinct. The main reason for their extinction was the Ice Age. The Ice Age caused food shortage and climate changes which made the Woolly Mammoth’s unable to survive.
Dodo Bird:
Dodo birds were first sighted in 1600 on an Island in the Indian Ocean. Less than 80 years later Dodo birds were declared to be extinct. Dodo birds were not fully preserved resulting in no complete Dodo specimens existing. With Dodo birds unlike Dinosaurs and Woolly Mammoth’s, the main reason for their extinction is because of humans. Humans came onto the island and would destroy the forests where their lived. This caused the Dodo’s bird food supply to be cut off which was a main reason for them becoming extinct. Also, when humans would come onto the island they would bring other animals along with them which would destroy the Dodo bird’s nests.
Tigers:
Over the years different types of tigers have become endangered and some even extinct. The main cause of tigers becoming endangered and extinct are humans. Many poachers hunt animals and sell their skin and body parts. Some of the uses for the animal skins and body parts are for medicine in Asia. Hunting tigers is also a sport which is a cause for their species becoming endangered. Also, humans destroy their habitat by cutting down the trees, causing pollution in the water and air, and kill the tiger’s prey. To get more specific Caspian tigers which became extinct by the 1950’s, were also heavily hunted but were also used by the Romans in arenas for entertainment. They would fight other animals as well as gladiators in arenas with a large audience.
http://www.edu.pe.ca/southernkings/tiger.htm
http://www.itsnature.org/rip/recently/caspian-tiger/
Whales:
Whales main cause for endangerment are humans. Humans have been killing whales, but there have become laws to try to prevent this. Humans also cause pollutions and oil spills which kills whales as well as other things in the ocean. Also, garbage humans throw into the ocean kills whales every year. Another cause for whales becoming extinct are when whales become sick the can become disoriented and end up beaching itself. If a whale is not put back into the ocean quickly enough it will die.
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