Almost all species use sex to reproduce, but biologists struggle to understand why; join Professor Lindsay Turnbull from the University of Oxford as she explains the costs and benefits
Sex puzzles biologists because it has a profound cost. Asexual species can potentially grow their populations much faster and so should outcompete their sexual cousins. But sexual species also produce genetically variable offspring - and in a changing environment, this can help them to stay ahead.
Sex also allows individuals within the same species to exchange genetic information, but they can't do this with members of other species. This genetic isolation allows species to follow separate evolutionary paths. These paths can be retraced by biologists using genome sequencing to build a tree of life.
Timestamps:
00:00 Intro
00:16 Titles
00:21 What exactly is sex?
02:22 Fertilisation explained
03:54 Sex in brief - recap
04:21 The problem - The Cost of Sex
05:42 So what is the point of sex?
08:15 How does sex create different species
10:30 Outro
