CrowdScience listener Bob wondered just this as he watched various sized dogs running amok in his local park: the Great Dane has a much larger brain than a Chihuahua’s, yet the job of ‘being a dog’ surely requires the same brain power. So why have a big brain if a small one would do?

A search for the answer takes Geoff Marsh to dog agility trials, behind the scenes at London’s Natural History Museum and a laboratory that studies bumble bees. It turns out that size does matter, but not in the way you might think.

Presenter: Geoff Marsh

Producer: Dom Byrne

(Photo: Great Dane HARLEQUIN and a chihuahua Getty Images)