Snails Save Energy by Re-Using Mucus Trails

In order to conserve valuable energy, snails essentially play a game of follow-the-leader, a new study finds.

Snails create trails of mucus to that help them glide across the ground, mainly in search of food or a partner, but making all that mucus uses up a lot of energy.

"Snails expend a lot of energy, probably a third, creating mucus," said Mark Davies of the University of Sunderland, lead author of the study published in the journal Proceedings of the Royal Society B. "This process is very taxing indeed--much more so than walking, swimming or flying."

Davies and his colleagues studied marine snails off the coast of Britain and discovered that to save some of this vital energy, the snails sometimes follow the existing mucus trails laid down by other snails to get around and so only have to create a fraction of the mucus needed to make a new trail.

"The fact that they can make savings has a knock on effect in as much as they have more energy to do other things like reproduce," Davies said.

The energy savings may also helps snails which live in environments where food is scarce, making the energy harder to replace.

Davies discovered the snails' reuse of trails by measuring the thickness of the mucus along the trails.

Biologists had long suspected that snails behaved this way, but this is the first study to directly observe it.

Davies said that it is likely that all snails use this means of cutting energy as they plod through life.