What is it about slugs that so repels us? After all, they are closely related to snails, with their pretty shells and (to some) their associations with gastronomy.
Their other relatives, shell-forming marine invertebrates from around the world, are highly desirable to collectors who want to own their exquisitely beautiful protective armour. But a slug?
Despite all of the adjectives at our disposal to describe these soft, glistening, moist, succulent, flexible, sleek and tender creatures, the only one that most people can come up with is ‘slimy’.
The reason why slugs suffer from such a poor image is, unfortunately, abundantly clear: they have the temerity to wear their slime on the outside, rather than on the inside like the rest of us.
So, it’s time to give these much-abused animals a PR makeover.
Here are five things you didn’t know about these amazing molluscs:
- If you’re a keen gardener, it’s no good just hunting the big ones. Pheromones in their slime trails tell junior slugs that large slugs are around; killing them simply frees up space for small individuals to move in.
- Slime trails are a tactical compromise. The slug loses water in its mucus, which restricts its activity to the cool damp of night or to rainy days, but the lubrication that slime offers saves energy that would otherwise be needed to overcome friction.
- Unlike snails, no slugs live in fresh water (sea slugs evolved separately, also losing their ancestral shells).
- Though soft-bodied, slugs are hard-toothed. Each has an oral cavity that contains as many as 100,000 tiny teeth on the ribbon-like radula, or tongue.
- Slugs may look smooth, but sometimes that’s an illusion – a few are covered in soft prickles. One such species is the hedgehog slug, Arion intermedius.