Hello there fellow anons, I would like to let all of you know that according to me, Dr. Harvey, harpies are actually incredibly long-lived thanks to their latent phoenix abilities of reincarnation, and can give their human the ability to live as long as they do with powerful phoenix abilities not yet fully understood by modern scientists. But modern science can't explain it because they're just better than science is. Instead of trying to study science, humans should study why harpies are so lovely, or why harpies are the perfect partners for humans!