In fact so do a lot of other animals, this walking on ‘feet’ business isn’t as simple as it seems. If you have a look at this photo something looks distinctly wrong about that bend in the middle. (Photo by Frank Vincentz)
And this one, that looks right for a finch, but isn’t it wrong for a knee?
If this is the view of a bird leg you’re used to, by now you’re probably confused. Thigh up the top, then the drumstick is really the calf and that knee certainly looks like it’s going the right way.
What is going on? Do their knees go backwards or forwards?
Relax, it’s fine. Really what’s happening is that feathers hide a multitude of sins, or in this case body parts. We are mixing up the bits we see on the roast and the bits we see on the live bird (at least I assume other people have this mental blink, I certainly do).
If you look at these chicken legs here complete with impressive spur, you’ll quickly realise that they aren’t the drumstick. The drumstick is the feathery bit up the top, the thigh is completely hidden. These are actually the chicken feet. It doesn’t help that you get birds named things like ‘red legged kittiwake’ or ‘yellow legged gull’ – anything that doesn’t have feathers on it is a foot, and the toes down the bottom are just the toes.
This skeleton makes it clear, especially if you look at the back leg. Up the top is the short, chunky thigh, completely hidden under the feathers along with the knee. Then comes the long slender calf, which would make your emu drumstick. The joint in the middle that we think of as a knee is actually the ankle, which is why it bends that way. Down the bottom are just the toes.
And for the visual, here’s a cassowary ‘standing’ on its ‘feet.’
Enjoy this article? Subscribe to the weekly newsletter to hear about them all. Or grab my RSS feed