Why Do They Use Cockroaches to Do Experiments?

Scientists have exposed cockroaches to radiation, tested their learning processes and assessed the combinations of female cockroach pheromones that can best be used to lure male roaches to their doom. The reasons for the popularity of cockroaches in research circles include the insects' hardiness, their relative harmlessness and the similarity of their brains to the brains of human beings.

  1. They are Tough

    • It is an oft-cited cliche that in the event of a nuclear war, the only living creatures left on Earth are likely to be the cockroaches. This comes from the capacity of a cockroach to withstand six to 15 times as much deadly radiation as a human could. Additionally, cockroaches can survive for a month without food, for 45 minutes without breathing and for up to a week without their heads. Whatever physical demands a given experiment asks of its subject, a cockroach is probably up to the task.

    They Pose Little Threat to Humans

    • Though the presence of cockroaches is not exactly a sign of a fine restaurant or well-kept home, they are relatively harmless in a clean, controlled laboratory setting. Many types of cockroaches commonly used in science experiments at the K-12 level, such as the Madagascan roach, do not bite when held and scurry along the floor rather than flying, making them easily captured. The roach's capacity to spread diseases, however, makes its reputation as a pest well-earned, so don't set your cockroaches free once you're done experimenting.

    Their brains

    • A University of Arizona study, in which researchers attached electrodes to the brains of cockroaches in order to map their brain cells, yielded some fascinating results. Like humans, cockroaches have a hippocampus that aids them with memory and navigation back to familiar places. Since insects and humans are thought to have a common biological ancestor from nearly a billion years ago, it may not be a stretch to look for the origins of consciousness in a cockroach's brain. By doing experiments on a cockroach's memory and capacity to process information, we are also learning about ourselves.

    They breed prodigiously

    • A typical cockroach mother has between 300 and 400 children in her lifetime, and there are an estimated 4,000 to 5,000 different species of cockroaches in the world. The plentiful availability of cockroaches in warm climates makes them an inexpensive experimental subject to purchase in large quantities, for lab scientists and schools alike.