Architects.In.Making: Polar Bears.

Polar bears live in a very specific habitat. They need the cold, ice and snow to live. That is why they are called "polar bears", and not "summer bears". Polar bears have very few natural threats in the polar region. They are on the top of the food chain and there are no other animals in the north that will threaten the polar bears. So why are the polar bears now on the threatened and endangered species list?

The main cause of the depleting number in this majestic creature is global warming. Global warming is caused by the human race. We have invented millions and millions of new products in the past century that contribute to the thinning of the ozone layer, causing the earth to heat up, melting the polar bears' homes - the sea ice in the north pole.

Polar bears eat mostly seals and other fatty marine mammals that they hunt from the ice. As you can see, these innocent polar bears don't know what is happening to them. As the ice climate gets warmer, ice is melting early in the summer and freezing later in the winter. Polar bears spend less time on the sea ice, which means they have less time to hunt seals and build up fat reserves. This can mean female polar bears have trouble providing milk for their young. If female bears don't reach a minimum weight, they won't give birth at all. On top of that, the bears will eat one another when they cannot find enough food to fill their tummies. :(

Oil spills from tankers also threaten polar bears' lives. When their fur is covered with oil, the fur loses its insulating properties. The oil spills will also contaminate the food sources of the polar bears. That will make the polar bears ill or even die of poisoning.

Today, polar bears are also hunted by native Arctic populations primarily for food, clothing, handicrafts, and sale of skins. Polar bears are also killed in defense of people or property. However, Hunting is government-regulated in Canada, Greenland, and the United States. Hunting is currently banned in Norway and Russia.