Shells: Next time you go to the beach, take a closer look at the world at your feet
I love to collect shells. I can't go to the beach without picking one up. Then I pick up another. Soon, my pockets are stuffed with shells and I'm cradling a pile in my T-shirt.
My grandparents introduced me to shell collecting when I was eight years old. They had a tiny beach house in Cape May, N.J., a few blocks from the bay.
Every morning my grandmother and I would rise with the sun, grab our plastic pails, and head up the sand-blown street to the ocean. We never knew what we were going to find, which is part of the fun of collecting shells.
We'd almost always get a few clams and mussels and moon shells. On a good day we'd bring home a knobbed whelk that wasn't broken or an Atlantic bay scallop that was still hinged together.
Our most unusual outing was the day we brought home not shells but golf balls - dozens of them. They had fallen off a boat, and the tide scattered them all over the sand.
Still, I'd rather collect shells than golf balls. No two shells are alike. The tiniest ones are no bigger than the head of a pin. The biggest ones - from giant clams - can be four feet long and weigh hundreds of pounds. (That's a lot of chowder!)
Shells have been around for more than 500 million years. People have used them for musical instruments (conch-shell trumpets), spoons, jewelry, and even money (beads made from special shells were called wampum).
Conchologists (conk-AHL-uh-jists) are people who collect and study shells. They estimate there are from 50,000 to 200,000 different shells in the world today.
So what's a shell, anyway?
A shell is the protective layer or external skeleton that once surrounded soft-bodied animals.
Most seashells are mollusks, a group of animals that includes snails, clams, oysters, and mussels.
These animals make shells by growing a thin protein layer over their body, like your fingernail. Then the layer hardens, forming a shell. Most animals can't survive if they are separated from their shells. When an animal dies or loses its shell, the shell may be washed ashore.
There are five main kinds of seashells:
1. Gastropods: snails, whelks; single, coiled shells. Live animals often have a trap door over the opening called an operculum (oh-PER-kyoo-lum).
2. Bivalves (BYE-valves): clams, oysters, mussels, scallops. When they're alive, these animals usually have their hinged, two-part shells slightly open for breathing and eating. Their strong muscles can close the shells tight.
3. Tusk shells: there are few of these; they look like long pointy teeth.
4. Chitons (KYE-tuns): shield-shaped shells; mostly found in the Caribbean and South America.
5. Cephalopods (SEF-uh-low-pods): notably the helmet-shaped, free-swimming chambered nautilus.
So next time you're at the beach and you spot something, instead of just saying "Hey look, a shell," you can say: "Guess what I found? A gastropod - and it still has its operculum!"
*When a hermit crab needs a bigger shell, it seeks a larger empty one made by some other animal and moves in. Without a shell, it's naked.
*Scallops have dozens of eyes. They help scallops see predators. Scallops swim without fins or a tail by squirting jets of water out their shells.
*Have you ever put a large shell to your ear and heard oceanlike sounds? What you're really hearing are echoes of surrounding sounds, which the shell's shape jumbles and amplifies.
*Ninety-nine percent of all snail species have shell whorls that coil in a clockwise direction.
*Most mollusks (soft-bodied animals with shells) are capable of making pearls when foreign substances enter their shells. They coat the grit with shelly material. It takes about two years to grow a pearl. Some large clams can grow pearls as big as golf balls in 10 years.
Tips for Getting Started
*The best time to collect shells is right after a storm (strong waves push more shells to shore) and at low tide. Check your local paper for times. Local TV news shows often give tide times during the weather segment.
*Most of the shells you'll find won't contain live animals. Put back the ones that do. Some states outlaw "live shelling."
*Some of the prettiest shells are those too small to spot. Bring a screen or sieve to the beach and sift through some sand at the water's edge. Use a magnifying glass to examine what remains.
*To clean your shells, rinse them off, then soak them in fresh water overnight. Change the water and soak longer if needed. (Some people add a teaspoon of bleach to each quart of water to disinfect shells; this also fades the color. Ask an adult to help you.) Sun also fades shells; air dry them in the shade.
*Store your shells in clear plastic containers out of the light. (Look in hardware stores for suitable boxes.) Note where and when you found each shell.
Books About Shells
One of these might be a good companion on your next shelling trip. They all have colorful pictures and easy-to-read descriptions of shells around the world. Ask your local librarian for help.
The Eyewitness Handbook of Shells
S. Peter Dance
Dorling Kindersley, 1992
Seashells of North America
R. Tucker Abbott
Golden Press, 1969
R. Tucker Abbott
Golden Press, 1962.