Biodiversity is the variety of species in a specific area. This is very important to preserve because it will keep the area different and keep the ecosystem from being disrupted. Which could cause many animals in the ecosystem to go extinct and disrupt the ecosystem even more or completely dissolve it. Some possible threats that pose a danger to ecosystems are overpopulation which is when one species of animal are growing past the carrying capacity of other animals and are pushing them out which could make their population drop to extreme lows or even drop to extinction. Another threat to an ecosystem is a natural disaster which could wipe out all the food in the area, an example of that is a fire, it could go through destroy all food and most of the ecosystems habitat and make all the species populations drop to low numbers because of the lack of food and the lack of habitat to live in. Another threat in an ecosystem is pollution, it could pollute the water of a lake ecosystem and all the fish could die in the lake which would upset the ecosystem with no food for any animals that rely on fish to get them through the day. It could also damage the ecosystem in another way by giving the animals no water because of how all the water in the area is contaminated with pollution. Another threat to an ecosystem is human expansion which could quickly wipe out the habitat to make room for buildings. That could wipe out the habitat and food for species in that ecosystem which could devastate the animals in that area that they no longer are in that area. In the New York area the are a multitude of animals that range from mammals, reptiles, amphibians, fish, eels, and birds. Some of the animals in the area are bear, lynx, cougar, coyote, deer, moose, songbirds, and waterfowl. The life cycles of these animals have the normal life cycles of birth, young adult, reproduce, adult, and death. Some of the environmental influences are humans and their expansion which is destroying their habitat. Another threat that originate from humans is hunting which in the 19th century took out around 95% of the deer population in New York.