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Extinction

Extinction is the wiping out of a species forever. 

Reasons for extinction

• Rarity (when there are very few animals of a species left e.g. Galapagos tortoise) 
• Limited dispersal ability (This happens when an animal's habitat is destroyed and it can't adapt to another habitat e.g. the spotted owl in the Pacific Northwest because of the trees being cut down for logging)
• Inbreeding (when animals mate too much within their own group the offspring become less able to survive and adapt in a healthy way e.g Pandas)
• Hybridization (When two animals from different sub-species mate, they might pass on genes that are less healthy)
• Successional loss of habitat (When an animal's habitat is slowly destroyed and they have nowhere to live e.g. the Bali tiger which is now extinct, was forced to move to the mountains when the forests were cut down.)  
• Long-term environmental trends (e.g. Scientists think that dinosaurs became extinct because of a slow cooling of the earth)
• Catastrophe (e.g The island of Krakatoa in Indonesia was destroyed by a volcanic eruption and all life on the island died).
• Extinction of reduction of mutualist population (When species are dependent on each other, when one becomes threatened, it affects the other species e.g. 
• Competition (When a new species is introduced to a habitat e.g. when pigs were brought to Hawaii, they ate the nene goose's eggs and the goose became endangered.) 
• Predators (When the population of a species of predator in a habitat suddenly increases, the population of their prey decreases e.g. the brown tree snake population in Guam increased and its prey, the Guam flycatcher became extinct in 1980) 
• Disease
• Hunting and collecting (the Javan rhino)

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