original: only traits that help us survive and reproduce are transmitted .
simplifications: only traits that help us survive and reproduce are transmitted . only traits that help us live and reproduce are passed on . the traits that help is survive and reproduce are transmitted . only traits that help us survive and reproduce are passed on . only traits that help us survive and reproduce are transmitted . 1 . only qualities that help us live and breed are passed on . only characteristics that help us survive and reproduce are transmitted . only characteristics that support endurance and reproduction are passed on .