David Farnowski, age 12, of Duluth, Minn., for his question:
How do worms multiply?
Many teen age business persons are raising earthworms to help re¬plenish our depleted and polluted farmlands. When raising rabbits, it is necessary to start with at least one male and female pair. But to start a thriving colony of worms this problem does not arise. In the right liv¬ing conditions, any two earthworms start multiplying because each is both male arid female, a potential mother and father.
Though a newly hatched worm never knows his parents, he has both a mother and a father. This complicated family relationship is possible because the earthworm has workable male and female sex organs. This means that any two of them can multiply and produce a couple of separate, though very closely related families.
A couple of worms tend to pair off when the weather is moist and warmish. Then each crawls off to live his her solitary life in an under¬ground burrow. Later, each parent lays a batch of eggs. The mother of o~na batch is the father of the eggs laid by the other parent.
Each parent has a swollen garter around the body. It is near the head end in a segment called the saddle. Each parent lays a batch of tiny round eggs into a case of soft skin in the saddle region of his her partner. As the eggs develop, the egg cases leave the saddle and move forward along the wormy bodies of their parents.
After about two weeks, the egg cases slip over their parents' heads. They snap shut, holding their batches of eggs in little brown bags about the size of wheat grains. The parents pay no attention to this event. Both crawl away to continue their solitary lives, hiding in burrows and searching for moldy vegetation. Their precious egg sacs are left behind on the moist warm ground.
After another two weeks or so, the little eggs are ready to hatch. The hungry youngsters are miniature copies of their parents, and .too small to notice. It takes a row of six of them to measure an inch. The little creatures crawl offin different directions, searching always searching for banquets of decaying vegetation.
For several weeks, life is very hazardous and most of the wormlets are devoured by birds, insects and other foes. But as the survivors grow bigger, they soon set about digging typical earthworm burrows for themselves. When they can go below to escape their hungry foes and the drying effects of daylight, life becomes less hazardous.
Earthworms reproduce several times during the spring and summer seasons. If all goes well, a youngster is fully grown in about tyro years. He she is ready to repeat the remarkable process of earthworm reproduction. Usually an earthworm stays pretty close to home territory. No doubt the members of the complicated families sometimes meet and mate. But none of them ever know or care about who is related to whom.