Post your response to the following: Describe an example of how natural selection impacted the evolution of a particular species. Include outside sources if applicable.
One of the most fascinating species that is definitely a product of natural selection is the whale (Whale, 2008). Imagine a fish that breathes air? What could possibly be the point of such a creature? Why are there not land animals that only breathe water? Most would assume that whales are the evolutionary link from fish to mammals; however, it is actually the other way around. Fossil records indicate that whales evolved from mammals. In fact, the closes relative to the whale is the hippo. Whales have specialized lungs and circulatory systems that allow up to two hours of submersion without the additional intake of oxygen. I could not find any information on exactly how whales evolved from their land-dwelling counterparts, but it is clear that isolation played a very big role in the evolution of the whale. There is no bigger natural barrier than the open sea for non-flying mammals. I would assume that once the predecessors of whales got out into the ocean it did not take long for natural selection to take root and decisively change their anatomy.
Whale: Origins and taxonomy. (2008). Retrieved January 22, 2008, from Wikipedia Web site: http://en.wikipedia.org/wiki/Whale
Pruitt, N. L., & Underwood, L. S. (2006). Bioinquiry: Making connections in biology (3rd ed.). Hoboken, NJ: John Wiley & Sons, Inc.