Slugs and snails move using a foot – yes, a foot! This muscular organ stretches along the bottom of the gastropod’s body. If you place a slug or snail on a sheet of glass and watch it move from below, you’ll see a rippling effect travel the length of its foot, from back to front.
For a while, scientists thought that these contractions caused the animal’s sticky mucus coat to liquefy, allowing the waves to slide the foot forward in sections.
But new research shows that the contractions actually lift the foot off the ground to move it, so the mucus is only needed when the animal is climbing vertical surfaces or moving upside-down.
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