Sometimes, two different animals will evolve to have a similar adaptation, even when they are not closely related. Flight is an excellent example.
Biologists investigated whether birds that search for multiple mates would evolve ever more elaborate songs to attract them. What they found might have surprised Darwin.
If animals are dying from a human-induced threat, then surely we have a responsibility to help them.
Parents' DNA try to manipulate one another in a bid to shape junior in their mould.