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Earthworms. Although they are undoubtedly among nature’s humblest creatures, they are also invaluable for the survival of countless other species.
You probably don’t spend much time thinking about earthworms unless you happen to dig one up while gardening or see them lying on the sidewalk after a rainstorm. But earthworms are constantly hard at work, aerating the soil, allowing water to enter, breaking down organic matter, and releasing nutrients, thus allowing crops to grow. They are especially effective at adding calcium, nitrogen, phosphorus, and potassium into the soil.
Because we see them so seldom, it’s easy to forget just how many earthworms there are in our world, or even in our backyards. There are thousands of earthworm species, ranging from those under an inch long to whoppers that measure over a foot. Earthworms are also a good indicator of how healthy the soil is. Although estimates of their population density vary significantly, an acre of soil can contain around a million earthworms.
The incredible, underrated earthworms under our feet:
- Although earthworms don’t have ears, they can still sense vibrations. Charles Darwin, who studied them for decades, conducted an experiment in which he placed worms in a pot of soil on top of his piano. As soon as he started playing, they began burrowing underground, just as they would to escape predators such moles. However, this vibration-sensing ability can backfire – researchers think the reason earthworms come to the surface after a heavy rain is that they mistake the vibrations of raindrops for the movement of underground predators.
- Experiments have shown that earthworms are both smarter and stronger than we realized. In some experiments, they have become better at navigating mazes after repeated attempts. And they can burrow through soil thanks to their ability to push 10 times their bodyweight. Baby earthworms are even stronger, relative to their size, with the ability to push 500 times their bodyweight.
- It’s a common belief that earthworms can regenerate loss segments, or even become two worms if cut in half. However, this ability varies significantly based on the specific species. Most worms can survive having their tail segments cut off, but only some have the ability regrow head segments.