Every animal needs energy to live, and they usually get it by ingesting other living things. We’ve all seen videos of predators hunting down and killing their favorite prey, or docile herbivores munching on grass, leaves, or berries. But one group of animals has evolved a strategy to harness energy that’s a bit more complex and far more clever than simply finding something and eating it. Sacoglossan sea slugs are close relatives of the more colorful and better-known group of slugs called nudibranchs.
Nudibranchs are carnivorous – they prey on sponges, cnidarians, bryozoans, and even cannibalize other members of their own species. Sacoglossans, on the other hand, are more like their hippie vegan cousins. They feed on green algae using a specialized tooth-like feeding structure common to all snails and slugs called a radula. A sacoglossan sea slug uses its radula to pierce cell walls, allowing it to suck out all those sweet, sweet algal juices.
Okay, so some sea slugs are vegan, but what’s so clever about that? Continue reading