What is the closest living relative of the whale? You are wrong if you said dolphin or porpoise but correct if you guessed hippopotamus. New research into the genetic history of species by the Tokyo Institute of Technology and reported in the US Proceedings of the National Academy of Sciences delivered this unlikely relationship.
The researchers also found that whales are more closely related to cows, camels and pigs than they are to horses, elephants and sea cows. The scientists were studying a combination of long and short DNA strings found in various apparently unrelated species, strings which, once inserted by natural selection, are seen in similar locations in related species. The technique may force a re-evaluation of current species classification.