In the final programme in the current series
Geoff Watts visits Vancouver Aquarium, Canada, to talk to researchers who are usinggenetics to work out the mating strategies of local killer whales. Groups of killer whales are remarkably stable, with males and females often staying in their pods for life. So how do they keep the gene pool healthy and avoid inbreeding? Producer Alexandra Feachem. E-MAil: scirad@bbc.co.uk