Extinction is the process in which groups of organisms (species) die out. (www.biochem.northwestern.edu). A species becomes extinct when the last existing member of that species dies.

According to our research, the main cause of extinction is:

Habit Loss

as a result of human demand. That is Rainforests are the main habitats for tropical animals. There are huge demands laid constantly on forests by various parties. These are:

Though other reasons exist, habitat loss as a result of human demand, is widely considered to be the most important cause of animal extinction.
That is Rainforests are the main habitats for tropical animals.
There are huge demands laid constantly on forests by various parties.
They are :

Impact on Eco-Sysytem

Habitat changes reduce ecosystem health. That is each piece of habitat may not seem important individually, but there are combined effects. Research shows that roughly, when 90% of the habitat is eliminated, 50% of the species will be lost …

The larger species such as large carnivores, suffer first. Because those groups often contribute to healthy ecosystem processes, a wave of secondary losses may follow their decline.
Animals that conflict with people are also the victims of intensive eradication efforts.

When a habitat is split, some species die as a direct result of lost resources. Other species survive in reduced numbers in the habitat splits, but their helplessness to extinction increases. Populations existing in waste become prone  to genetic disorders and other sorts of problems.

These split populations are especially prone to events, such as openness to poaching.
 
Endemic species: That is those present only in a certain geographical location are more prone to extinction due to habitat loss.