The human CFTR (cystic fibrosis trans-membrane regulator) gene is 99% identical to the CFTR gene from chimpanzees. What does this mean?
O Chimpanzees and humans are actually the same species.
O Humans evolved from extant chimpanzees.
O Humans and chimpanzees must have mated in the past.
O The most recent ancestors of both humans and chimpanzees probably lived on earth more recently than the most recent ancestors of humans and mice.
O None of the above.
