Beetles in the Burial Business

Consider the occupation of the sexton beetle. This little fellow is an undertaker! Attracted by the putrid smell, he and his mate hurry to bury dead mice, frogs, snakes, lizards, squirrels, rabbits and other similar-sized carcasses.

How do they do this? Obviously, each dead body presents new burial problems, the size and position of the body being different in each case. Also, the ground upon which it lies varies from place to place.

First, these beetles inspect the carcass by walking all over it and around it. Having done this to their satisfaction, they then crawl under it. Using their tiny heads and feet as digging tools, they begin an undermining operation by throwing out the soil from beneath the body. The male usually does most of the digging. The female tunnels her way into the carcass’s interior, there to lay her eggs. The work is hard and slow but they are steady at it. Every now and then they take short rest “breaks.” Little by little the body sinks into the earth, its own weight carrying it down.

About two weeks after burial, the beetle’s eggs, laid in the carcass, hatch. And there, in that foul-smelling nursery, the young sexton beetles will live off the protein-rich dead flesh about them.

One scientist found that two of these beetles buried a mole three inches under the ground in one night. He was amazed, for this feat was comparable to two men finding a dead elephant and burying it twenty feet beneath the earth in twelve hours! He experimented with these insects. In fifty days they buried twelve bodies of frogs, fish, birds and quadrupeds.

Another insect with an unusual occupation is the tumblebug or dung beetle. He and his kind roll balls of dung around, often many times their size and weight. In the same way that children roll huge snowballs, these beetles build their smelly spheres to a certain size and then bury them. Watching them roll a dung ball is amusing. Often they tumble or fall over, get back on their feet and go at it again. Hence their name tumblebug.

While these scavenger insects help to keep the ground clean, their odorous occupation serves their own interests. Inside those dung globes are eggs that they have laid. So when their young are born, they feed on this decaying matter.

Leaf-carrying Farmers

Abundant in the American tropics are the leaf-carrying ants. Their occupation is unusual. They will march quickly in two columns, one column going to and the other coming from a bush or tree that may be a mile or more away from their nest. Those in the returning line carry pieces of leaves over their backs.

Watching them at work is intriguing. They climb up a tree or bush, choose a leaf, and then, using their jaws like scissors, rapidly cut two converging slits in it that almost meet. A quick jerk and the triangular piece of greenery is ripped off. Each ant usually does his own cutting. But at times, one may do the cutting while the others on the ground pick up the dropped pieces and carry them off. When the cutter gets tired, he is relieved by another ant from below and he descends to join the carrying crew.

These ants tote loads weighing up to four times as much as they do, and that for a mile or more! In ant proportions, naturalist A. Hyatt Verrill says, their travels in just one day have been calculated to equal what to us would be nearly three thousand miles! To appreciate this, imagine a man marching rapidly from New York to California in one day and coming back the next day, day after day, week after week. And on each return trip he carries a two- or three-hundred-pound load!

Why do these ants engage in this strenuous work? They do it as part of their main occupation. What is that? Farming! The leaves they secure are food for a mushroom or fungus bed that they cultivate in their nest. First, they shred the leaves, chewing them into little balls or pellets. Then they press these into the surface of their garden. In a short time, the pellets become covered with a fungus growth of fine white threads. And the liquid that these threads produce serves as food for these leaf-carrying farmers.