There are thousands of thousands of living organisms in our environment, varying from animals to plants and to the smallest microorganisms. These living entities in their own group form balanced feeding enablement for the general ecosystem in the form of what is referred to as the food chain. A seem tragedy that is setting in is due to the extinction of these organisms in our environment as civilization and urbanization are increasing. These species of living organisms are becoming threatened and endangered.
Threatened and endangered are two good terms that can be used to refer to and relate well with this kind of scenario. Threatened in the sense that a species or organism is either threatening another, or it's being threatened by another organism, which is making some species going into extinction. Endangered also refer to a risky living by organisms, and this phenomenon also leads to extinction. Extinction is actually a state of an organism being removed from existence due to harmful or fatal occurrence.
Threatened and endangered species both refer to the type of animals that are in danger of reaching extinction but in varying degrees. Vulnerable means that the animals are disappearing at an alarming rate, and there is a possibility that they will become endangered in the long run. Endangered means that a large number of animals are already gone and there is a big possibility that they will become lost.
There are already a lot of animals that have become extinct throughout the years. Some of them did not survive because they lacked the food to live while there are also others that have become extinct because of all the hunting that people have done throughout the years.