Wayne State University professor Morris Goodman was quoted in Time's cover story about how similar humans and apes are. The chimps are humans' nearest evolutionary cousins, roughly 98-99 percent identical at the genetic level. Goodman said that it wasn't until the 1960s that the human/ape relationship started to be understood at the level of basic biochemistry. He noted an experiment where a chicken was injected with a specific blood protein from a human, which provoked a specific response. The same response was elicited when the chicken was injected with a specific blood protein from a chimp and a gorilla.