Amazon River Dolphin

The amazon river dolphin lives in the amazon rainforest in the present day. It has a pinkish color on its skin, its scientific name is inia geoffrensis, it has sharp, black teeth and a long but narrow mouth. Its diet consists of different types of fish like catfish, and tetras. Now lets say the amazon rainforest has become as cold as the arctic after the past 5,000 years. Now the river dolphin has evolved to have much darker skin so it can absorb the warmth of the sun. The river dolphins ability to jump out of the water comes into use because food has become scarce underwater so it can jump out of the water to catch low flying birds. It can be up to 400 pounds and be 16 ft long, so now it has more body fat to contain warmth.