Five distinct types of dog existed by end of last ice age, study finds

Research suggests canines' varied origins stretch back further - and live on in today's pets

From tiny chihuahuas to fluffy Siberian huskies, dogs come in all shapes and sizes. But researchers have revealed there is more to canine diversity than meets the eye.

Scientists have found five distinct groups of dogs were already present at the end of the last ice age, and their legacy lives on in our pets today.