Episode Details

All this week we’ve looked at the claim that our bodies are full of useless evolutionary leftovers, and we’ve seen this argument is, well, useless!

As our last example, we’ll look at goosebumps. These bumps form when tiny muscles contract, pulling the hair upright. In furry mammals, this helps increase fur’s insulation but, since it doesn’t do that for us, some people say goosebumps are useless. But this muscle action creates extra heat, draws oil to your skin as moisturizer, and heightens our sensitivity in a threatening situation.

Since we didn’t evolve, we don’t have useless structures.

Dig Deeper

• Setting the Record Straight on Vestigial Organs
• Skin