Soils

 

Soils are getting too moist for the top worm.

A recent warming spell has been good for all soil dwellers except one. The apex predator of the driest soils in the Dry Valleys food chain isn’t a lion or a killer whale, it’s a slender, microscopic worm called a nematode! The most numerous species, Scottnema lindsayae, seems to be dying off. Other organisms are multiplying, but their numbers aren’t growing fast enough. S. lindsayae, which lives only in Antarctica, is a major player in the ground. So if it disappears without a successor, other species—and all the soil ecosystems—will be at risk, too.

 

Header photo: Wright Valley in the McMurdo Dry Valleys. (Collin Harris / Era Images)

These mosses would tower over the local microscopic animals like redwood trees.

Moss patch found in the Dry Valleys (Becky Ball / NSF)?

S. lindsayae (left) has ruled the dry soil. But E. antarcticus (right) does better when it’s wetter—plus, it will eat anything, including S. lindsayae.

For scale: A full grown nematode is the size of a period in 12pt type. It is as big around as 3 of your hairs.

S. lindsayae and E. antarcticus (J.D. Eisenback / Virginia Tech)