In this episode we ask: how do woodpeckers avoid concussion? Why are giraffes' tongues black? How can ants survive a flood? How do octopuses squeeze into tiny spaces?

In this episode we ask: how do dogs detect underwater targets? What makes ostriches nature's best marathon runners? How do sloths spend so much time upside down without passing out? And can a pelican bill really hold more than his belly can?