APRIL
2000

 

 

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

 

 

 

 

04-13-00

Battle of the Sexes - Insect Style

With humans, it began with Adam and Eve. Insects, it seems, have been at it even longer. Yes, the battle of the sexes is not just for people!

Some of the really big gender behavioral issues that bug humans don't bother insects. For instance, whether the toilet seat should be left up or down isn't an insect thing. Neither is the propensity to assume that males won't ask directions. Shopping and moving furniture? Not an issue with insects.

But there are behavioral differences in insects that are sex-related. For instance, mate selection. In the insect world, a common approach to mate location is that the female allures and the male pursues.

For many insects that means using a pheromone, a perfume, to attract a mate. In insects. the use of pheromones is a decidedly distaff thing. With a few exceptions, pheromones are produced by female insects.

But then, that hardly sets insects apart from humans. If you aren't convinced, just take a look at the cosmetic section in your favorite store. You will find that the selection of artificial odors for women far outnumber those for men.

Sounds are also used by insects to attract mates; mostly, it is the male insect that produces sounds for the purpose of attracting a female. The process is known as singing. The exception to males producing the mating sound is in some flies and mosquitoes. In these insects, the hum produced by the wings of the female during flight attracts the male of the species.

Many people assume that singing katydids are female. Perhaps, it is because the common name of the insect, katy, suggests it. Some poets have also been confused about the sex of the singing katydids. Oliver Wendell Holmes in his poem “Katydid” states:

“Thou are a female Katydid
I know it by the trill
That quivers through thy piercing notes,
So petulant and shrill.”

Philip Freneau also assumes that this insect is female. In his poem “To a Caty-did,” he uses female pronouns in reference to the insect: “Hear her singing in the shade” and “Caty now will do her best, All she can, to make you blest.” But poets aside, any katydid, grasshopper or cricket that sings is a male!

Child care, where it occurs in insects, is mostly left up to the females. The eggs may just be hidden in a safe location, such as the soil or inside the stem of a plant. Some insects, such as the cockroaches and preying mantids, place the eggs in an egg case. But whether protected or not, when the young insects hatch they are on their own.

In social insects, the workers, which are females, do all of the kid care. They feed, clean up after and pamper the larvae until they turn into adults.

In fact, all of the work of the social insect colonies, including honey bees, bumble bees, ants, termites and some wasps, is done by female insects. Even the head of the colony is a female. Called the queen, she lays the eggs and generally is in charge of the rest of the colony, most of which are females. Each colony does have some males. These males, in the bees, are called drones.

Drones have only one function, to mate with a queen. In between flights to search for queens, the drones lounge around the hive and are fed by the workers. A good life, except there is a catch. When winter rolls around, the females of the hive perceive drones as a liability and toss them from the hive.

Now being tossed from your home is the ultimate in the feud between the sexes. It kind of makes being browbeaten for not stopping to ask directions seem mild. Maybe it has to do with the lack of a pheromone!

 

Writer: Tom Turpin
Editor: Olivia Maddox