Yes I am about a week behind in this show but that’s the beauty of catch-up and the BBC iplayer! The third episode of Secrets of Bones focused on the flying and how bones have enabled flying to become a way of locomotion.
The programme starts with explaining the three different times that the wind and flight has evolved; once in the dinosaurs, once in bats and of course also in birds. Although these three groups of animals have evolved to fly they have achieved this in different ways. Each one has a similar structure in the wing bones, that is they all possess a pentadactly limb (see more on this from my post on episode 2). However, they way in which these bones are organised differ providing different methods to achieve flight making this a perfect example of convergent evolution. I don’t I can explain each type of flight clearly enough to make it easily understandable so I highly recommend either watching the show if you haven’t already or to have a look at this site entitled ‘The Three Solutions to Flight‘ from Berkley. It also appears to have been originally written by John Hutchinson who also appears on the show.
After discussing the three different types of flight the programme focused on the variation found in birds with regards to their wings, and skeleton. It showed that although the majority of birds fly their bones differ with regard to size and shape. For example the pigeon has a massive keel on it’s breast bone for muscle attachment to enable a vertical lift whilst the albatross have a massive wing-span which has the ability to lock itself, which means the albatross can glide over great distances.
Once some of the flying birds were looked at the focus shifted to flightless birds including the emu and penguin. Ben Garrod showed how again these birds different and how their skeleton had adapted to the different needs. This meant that the emu had strong, light weight bones to assist with running whilst the penguins bones are much denser to act as ballast.
I really enjoyed the episode – it probably wasn’t my favorite; but that’s probably because I am much more interested in mammals. It was delivered in a very competent and clear manner and definitely think osteology courses should look at including this.