How Cockroaches Could Save Lives

Cockroaches are often associated with dirty kitchens and grimy bathrooms - scuttling away as soon as you enter the room and turn on the light. But pest controllers aren't the only people interested in them - these insects are inspiring research into antibiotics, robots and mechanical limbs, writes Mary Colwell.

In Havana the native bright green Cuban cockroach is often kept as a pet and the insect even appears in old folktales. In one story, a beautiful young Cuban cockroach called Martina tests the character of her suitors by annoying them when they come to visit.
"Drop coffee on their shoes to see how they react," recommends her wise grandma. "It is very important to know what your future husband is like when he is angry - the coffee test never fails."
When faced with soaking wet shoes, her rich suitors show their true colours. A kind and gentle but poor hopeful passes the test though, and the couple live happily ever after.
Wise and beautiful are words not often associated with these creatures but their bad reputation is not always justified. Out of the 4,500 known species, only four are considered pests. Most don't live near human homes and they perform a vital ecological role, eating dead and decaying matter.

Some species are exquisite with brilliant colours and patterns. Some are social and make collective decisions, passing on information about food and shelter. Others are solitary. Some pair up and raise their young together. They can hiss, sing and make drumming sounds to attract a mate, and they are supremely hardy, surviving on the most meagre rations for months on end. One, the Eublaberus posticus, can survive for a year on water alone.
The heaviest, the subterranean rhinoceros cockroach, weighs in at 35g, measures 8cm in length, and lives in Australia. One of the smallest is a pest commonly found in Europe and North America - the German cockroach, which is just over 1cm long. Martina and her grandma might be interested to know that coffee grounds are often used as bait to trap them.