John Grehan, of the Buffalo Museum of Science in New York State, and Jeffrey Schwartz, of the University of Pittsburgh in Pennsylvania, say that the DNA evidence cited by many scientists only looks at a small percentage of the human and chimp genomes.What's more, the genetic similarities likely include many ancient DNA traits that are shared across a much broader group of animals.Humans share at least 28 unique physical characteristics with orangutans but only 2 with chimps and 7 with gorillas, the authors say.The finding, which has the potential to spark a radical rethink of human origins, is being met with caution."There are many paleontologists and molecular biologists who are heaping scorn on this paper," noted Peter Andrews of the Natural History Museum in London.
