Page 103 - Atlas Of The World's Strangest Animals

AMERICAN COCKROACH 103

responses to stimuli. Ivan Petrovich Pavlov (1849–1936) memory and a capacity to learn – something that had
was a Russian psychologist, famous for his work on previously been associated only with mammals.
conditioned reflexes. In a series of experiments in 1901, Further research has shown that cockroaches seem to be
Pavlov gave food to dogs every time a bell rang or a able to make complex decisions, such as allocating
whistle was blown (other stimuli were also used).The dogs resources to fulfil the needs of a group. In one study,
began to associate the stimuli with the arrival of food and 50 cockroaches were placed in a dish with three shelters,
would salivate even if they heard the noise and no food each of which could support 40 insects. Every time, the
was given. insects arranged themselves in two shelters with 25 insects
The Japanese researchers were stunned to find that in each, leaving the third shelter empty. In fact, Nicholas
cockroaches responded in the same way. In their tests, they Strausfeld, a neurobiologist at the University of Arizona,
exposed cockroaches to an odour whenever they fed them USA, has spent much of his career examining the brain
with a sugary solution.After several attempts, when the structures of tiny creatures like cockroaches, and his
cockroaches smelt the scent, they reacted as though food findings have lead him to suggest that insects may possess
was on its way.The implication is that ’roaches have a ‘the most sophisticated brains on this planet.’

With a body designed to take cover under logs and stones, it Once night falls, the ’roaches creep out of their hidey holes
has no trouble keeping itself concealed in a modern home. and start to search for food – and any food will do!

These unwanted guests are fast on their feet, but even if you Hidden away and protected from harm inside this tough little
catch one, there’s always plenty more to take their place. egg case are dozens of baby ’roaches waiting to hatch.

(c) 2011 Marshall Cavendish. All Rights Reserved.