As April brings in a season of showers, there seem to be a lot more worms on campus. Worms come up from the ground during a rainstorm and slide across sidewalks, pavement and parking lots.
There are many reasons why scientists believe worms come up in the rain. According to my kindergarten teacher, worms come out of the dirt in order to get oxygen to breathe. The worm burrows fill with water and causes oxygen to move more slowly.
Worms do not have lungs so they cannot drown, but worms breathe in oxygen and out carbon dioxide like many other species. With no mouth and no nose, worms breathe through their skin, and a flood of water makes this a very difficult process.
Though this is taught to children most everywhere, other scientists say it is a myth. Only some worms need the amount of oxygen that only air can provide. Some worm species do just fine in water, as their oxygen intake is lower.
The other popular explanation for worms’ behavior is that worms come to the surface because rain sounds similar to predators like moles. Yet, this is still debated too as professor Thea Whitman of the University of Wisconsin points out that this idea has never been demonstrated in lab tests.
It is difficult to find a true answer for the worms’ actions, especially because there is no way for them to indicate why they do what they do. Regardless of why the worms have come out to say “hello,” you should watch your step walking around on a rainy day.
Worms are amazing, valuable creatures and decomposers. They bring air into the soil with their burrows and do vital nutrient cycling as they move through the dirt. They also help water move through the soil, and their existence assists plant growth.
Additionally, worms are an important food source for species that eat them, like foxes, moles, skunks, snails, snakes, salamanders, toads and, primarily, birds. Worms provide important protein and fats for birds and are a food birds can rely on all year-round, unlike berries and seeds. Not only do they provide food for plants, but animals as well, cementing their position as one of the more valuable critters in the food chain.
If you see a worm in the middle of a sidewalk, consider its life and contribution to the world. Worms are hard workers, and do all of this for free. You can help a few worms by simply moving them from the sidewalk into dirt or grass so they do not dry out in the sun or become victims of a sneaker.
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