I wasn't planning on posting tonight but just can't help myself. I've spent the past hour watching the BBC's Animal Odd Couples. It's one of the most endearing programmes I've seen for a while...
There were so many examples of animal couplings - demonstrating maternal instincts, brotherhood and love - that you could ever expect to see.
If you get a chance watch episode 1 or at least watch the clips (here's the link: http://www.bbc.co.uk/programmes/b03jp47m)
Cat and ducklings: