In class, we talked about some theories of what makes humans different from other animals. One theory we discussed was that humans were the only animals to make and use tools. Of course, Sally the crow proved this wrong! This theory was actually first disproven in 1960, when primatologist Jane Goodall showed chimpanzees make and use tools to fish termites, a favorite food, out of their mounds. Here's a video with chimpanzees using a couple different tools:
This made me wonder about what other theories have been put forth concerning the difference between humans and other animals. According to Wikipedia, Darwin and Aristotle both claimed humans had the greatest brain-to-body-mass ratio, which was the reason for their superiority. Humans do score highly on this measure (1:40). However, small birds have an even higher ratio (1:12) and shrews have the highest (1:10)! There's a more complicated version of this measure called the encephalization quotient, which compares actual brain size and expected brain size based off of the animal's size, and humans do have the highest score on this measure:
Looking at the graph, humans don't seem that much higher than other great apes. In some ways, this isn't that surprising considering our shared ancestry. But humans have always seen themselves as so advanced over all other animals. Looking at all this evidence, should humans really see ourselves as so superior? Or are the differences between other animals and us not so great?