Science Section: Rain & Earthworms

It’s been a while since the science section was featured here in blog land. The other day while walking to the lab, for some reason my brain was wandering, and I started to think about our friend the earthworm. Popular culture says come spring time, earthworms surface post rain to avoid drowning as the water filters down through the ground. Now my thoughts were, if this were truly true then given the incessant rain we have been experiencing I'd expect one of two things to have occurred: The surface of the ground would be covered with worms, which hasn't happened, or that the ground would be totally devoid of live earthworms as all of them would have drowned.

Well, a quick Google search reveled the truth, earthworms breath through their skin and water doesn't phase earth worms a bit. Infact earthworms can live fully immersed in water for weeks assuming the water contains adequate levels of dissolved oxygen. The earth worms real enemy isn't water but a lack of water, dehydration. The reason earthworms surface post rain is because post rain the surface humidity increases to level worms can more safely travel above ground, just don't tell the birds.