THE SIZE of an organism places many limits on its shape, physiology and behaviour, often in surprising ways. For instance, if we were scaled down to the size of mice by the absent-minded inventor from Honey, I Shrunk the Kids, we could happily fall from a cliff safe in the knowledge that after a bump, we could get up and walk away. Bigger animals would certainly be seriously hurt or killed in such falls.
But suppose we were scaled up to the size of the giant in Jack and the Beanstalk, our leg bones would no longer be thick enough…
