Follow a burrowing earthworm seeking soil's moisture to protect its oxygen-collecting skin

Cross-section view of an earthworm (Lumbricus) burrowing beneath the soil's surface

Encyclopædia Britannica, Inc.

Follow a burrowing earthworm seeking soil's moisture to protect its oxygen-collecting skin
See how game theory applies to the peacock's tail evolution
How Charles Darwin developed the theory of evolution
Discover how individual cilia employ viscous drag to coordinate power and recovery strokes for locomotion
Know how some spiders gallop through the water
Observe a pocket gopher using its front teeth and foreclaws to burrow a home full of roots, stems, and tubers
Visit Santiago Island, in the Galapagos Islands, where Charles Darwin spent weeks experimenting, observing, and collecting specimens of the unique Galapagos wildlife
Survival struggles in a meerkat colony
Know how the Galapagos finches from Charles Darwin's specimen collection helped him in the formulation of his theory of evolution, particularly the woodpecker finch

Transcript

NARRATOR: Earthworms take in oxygen through their skin, which must always remain moist. To maintain their skin moisture, earthworms live in burrows beneath the surface of the soil.

Endangered by too much light, they remain in their burrows during the day, emerging only at night or during periods of heavy rain.