Arthropod Animation: Scorpion Book Gills


Book gills are flaps located inside the scorpions body that transfer oxygen to the blood.

Next Generation Science Standards for this Video

The versatility of the arthropod body plan allowed them to diversify on land, inventing new ways to extract oxygen from air rather than water.

When arthropods invaded land and needed to extract oxygen from air instead of water, book gills, which functioned in water evolved into internal organs that function well on land.