The blue-footed booby (pictured) is an extraordinary-looking bird. It has fairly dull plumage but strikingly coloured blue legs and feet. What could be the evolutionary benefit of such a conspicuous feature? Both sexes have blue feet so they don't seem to be for impressing potential mates.

Sam Moore, London, UK

A gecko sticks to a vertical surface because of the huge surface area on its feet (thanks to microscopic hairs). If you ran the gecko's feet under a tap, (or dipped it in a pond), would the gecko just slide down/fall off the vertical surface, because it's feet were busy sticking to water molecules instead?

And if it did, would it have the emotional capacity or facial muscles to look surprised? 

I've just read your excellent book and have enjoyed it thoroughly

However the answer to the title question left me wondering a little as to be honest the answers given were more of a "why doesn't a Penguin lose too much heat through it's feet."

I've worked in a frozen food vendor and I know that on Mondays when the freezers were right down to temperature of near -30 I would stick to surfaces if I was daft enough to touch them (it had to be tried - not that I'm recommending it!).

I know really cold snow is powdery, but still that layer of cells in contact must be -30 or so on one side and above freezing on the other. Why are they not killed ?

Many animals have dead cells "fur etc." in contact, but not Penguins as far as I know

So if it's OK can I ask it again please

Regards

Andy

At the risk of flogging a dead, er, penguin. Why don't polar bears' feet freeze?

Paul Newcombe, Zurich, Switzerland

(Image: US federal government / Wikimedia Commons)