Balancing the Water
Vadim Trunov’s macro photos of snails (and other insects) in watery worlds are pretty stunning. Actually, they are totally stunning. Check out a slideshow here.
They remind me of why snails are found around water so much, and the simple chemistry of killing them with salt. Terrestrial snails (and slugs) are descended from aquatic creatures, all in the gastropod family. Although they have adapted to life outside of the water, they require a coating of mucus all over their exposed tissues to keep their soft tissues from drying out in the air. This water must constantly be resupplied from their environment, be it dew or a puddle.
When you pour salt on a snail or slug, you start an avalanche of osmosis, with water from inside the snail’s cells rushing out to try and balance the salt concentration inside and out. It dries up like a pickle. A murderous chemistry, no? Although if you salt them after they’re cooked, maybe with butter … they’re delicious.
(sketch via Janet Stemwedel)
A particular snake attacks snails in a particular way that breaks it out of its clockwise-spiral shell in seconds. It turns out that a single gene can create mirror-image counter-clockwise snails that the snake can’t figure out how to devour.