Gary Falco, age 10, of Staten Island, N.Y., for his question:
HOW DOES A HYDRA MOVE?
It’s fun to skip and leap along and certainly running is a, lot more fun than plain walking. But most young persons agree that turning cartwheels and somersaults is just about the greatest fun in the world. The cute little hydra agrees with this idea. In fact, the only way he can get from here to there is with a row of topsy turvy somersaults.
Most of us never meet a hydra because he lives under water. Besides, even the biggest hydra is only half an inch long and very, very skinny. He is almost too small to notice, especially when he decides to hunch down like a bumpy little button. Most of the time he looks like a skinny little tree with five or six skinny branches. He may be grayish, brownish or even bright green.
Actually, the hydra is not a minitree or any other kind of plant. Plants, as we know, must stay rooted to the spot. The hydra, when he wishes, can move himself from place to place. So he must be an animal, though no other animal travels around as he does. For each step he takes is a sprightly somersault.
His body is the part that looks like a minitree trunk and the skinny looking branches are really tentacles, used to grab bits of floating food. Then they act like fingers to stuff his snacks into his mouth, which is at the top of his trunk. Most of the time he stands up straight in one spot, with his skinny tentacles dangling through the water.
After a while he moves on to find food in another part of his pond. Then the fun begins. He bends his trunk and dips his tentacles down to touch the floor. When they are nicely settled, he lifts up the foot of his trunk and loops it right over to touch the ground. Then he lifts up his tentacles and flips them over to make another somersault.
His parade of topsy turvy somersaults is rather slow and surely it must be quite tiring. So sometimes he finds an easier way to get from here to there. He floats to the top of his pond and turns himself upside down. There he lets the moving water drift him along—with his tentacles dangling down and his foot just below the surface.
The hydra feeds on mini mini water creatures. His tentacles inject juices that stun his victims before he swallows them. Sometimes he produces eggs. But more often he sprouts a bumpy bud that develops into a baby hydra. When the budding baby is big enough, it breaks away and goes off on its own.