Spring rains often bring scores of earthworms to the surface, where they writhe on top of soil and sidewalks.
But recently, heavy rainfall in a town near New York City was followed by something a little more unusual: a wormnado.
Worms breathe through their skin, so when heavy or persistent rain saturates the soil with water, the worms must tunnel to the surface or risk drowning, according to the University of Wisconsin–Madison.
Earthworms are typically solitary, but they sometimes form herds when they're on the surface . The worms collect in groups and communicate with each other about where to move, researchers reported in 2010 in the International Journal of Behavioural Biology.
The scientists in that study found that earthworms in the species Eisenia fetida would form clusters and "influence each other to select a common direction during their migration," and they did so using touch rather than chemical signals.
This collective behavior could help earthworms survive environmental threats, such as flooding or arid soil, and it could also be a defense strategy against predators or pathogens, according to the study.
Source
But recently, heavy rainfall in a town near New York City was followed by something a little more unusual: a wormnado.
Worms breathe through their skin, so when heavy or persistent rain saturates the soil with water, the worms must tunnel to the surface or risk drowning, according to the University of Wisconsin–Madison.
Earthworms are typically solitary, but they sometimes form herds when they're on the surface . The worms collect in groups and communicate with each other about where to move, researchers reported in 2010 in the International Journal of Behavioural Biology.
The scientists in that study found that earthworms in the species Eisenia fetida would form clusters and "influence each other to select a common direction during their migration," and they did so using touch rather than chemical signals.
This collective behavior could help earthworms survive environmental threats, such as flooding or arid soil, and it could also be a defense strategy against predators or pathogens, according to the study.
Source