Snails Taking it Slow and Easy: Photos
Cuter than you might imagine, but just as slow as you think, these critters know how to pace themselves.
Imagine you have to carry a shell on your back and that you're driven to eat the right foods to nourish that shell, and that some consider you a pest while others consider you food. Now take into account that you're so slow that anything that wants to eat you probably can -- you're not a fleet-footed evader of predators. Welcome to the life of a snail. You'll never find 100% agreement that they're cute, but there's no denying that their grim determination makes them at least a bit noble. (OK, that might be a bridge too far, but you get the idea!) Herein we take a look at some of these slow-moving critters. Of course, the shell is a snail's biggest show-stopper. They'll vary widely in color by species and are usually made of calcium carbonate, forming a spiral shape. To make a shell, snails use a bit of their own hardware called a mantle -- a thin, skin-like organ that secretes a liquid made up of shell material. The liquid hardens and forms the shell. Over time, the mantle releases yet more liquid, adding to the size of the shell.
Snails can be nearly invisible to the naked eye or reach more than 1 foot long. They're found in fresh water, salt water, and on land. They get knocked for their, well, snail-like pace, but it's not like snails can't move at all. Locomotion for most snails is by means of a large flat foot -- more like a body-length muscle -- underneath them that helps them glide across layers of mucus they secrete to smooth their way forward. It will even leave some slime in its wake, if you watch closely for it. You might be wondering
slow they are. Given it's football season, we'll use 100 yards as a metric. If a garden snail were to receive a kickoff in its end zone and return it all the way for a touchdown, you would have to wait about two hours to see it reach the other end and spike the ball. And garden snails are the absolute speedsters of the snail world!
Land snails will typically eat fruit, dead plants, some live plants, and even bark. Freshwater snails will feast on algae, dead marine life remains and plants, while sea snails enjoy algae as their main course. Snails have rows of small teeth that sit in long, tongue-like organs called radulas. They don't chew their food so much as grind and tear it with these teeth.
Snails have eyes at the ends of the longer pair of their tentacles. Land snails can zoom these up, down and all around while a sea snail's eyes are at the base of its tentacles and don't move.
Of course, food in the animal kingdom is often a two-way street: You're either eating or being eaten. A snail has plenty of things that would like to eat it, so that's where its shell comes in. If a predator like a snake or a bird is nearby, a snail can crawl in its shell and seal it off. It can stay holed up like that for days to weeks if it wants to.
Remember the mantle, the snail's organ that secretes material for the shell? Land snails breathe using a lung set into it. Sea snails, meanwhile, breathe through gills. Like fish, they use them to get oxygen from the water. Freshwater snails sometimes have gills, too, while others have lungs. When the latter need to breathe air, they surface and take a gulp.
Land snail eggs are not much bigger than a letter on your computer screen. Over a couple of days, a land snail will lay up to 100 eggs, burying them in shallow holes covered with dirt and their own slime. Most won't survive predation; those that do will hatch in 2-4 weeks. Sea snails will deposit their eggs by the thousands on the ocean floor, though most won't fare any better than those on land. Freshwater snails may deposit their eggs above the water line, such as those of the apple snail, shown here.
Unfortunately for them, some species of snail, such as abalones and some land snails, are eaten by people. France, for example, raises them for that purpose. (Snail fans who don't see them as food will want to avert their eyes from escargot.)
There are tens of thousands of snail species, found in a vast array of climates and habitats -- from suburban gardens to mountainous areas; from marshes to the deep ocean.
Most snails are hermaphrodites, with both male and female reproductive organs. A mating ritual that can last several hours results in each snail having eggs to deliver, after they grow for a bit inside the snail. As we've seen, most young'ins won't make it, but a few will, and snails will find a way to keep on going.