Latest Important Animal Research: Case Western Reserve University researchers revealed in a December journal article that cockroaches do not age gracefully, that after about 60 weeks of adulthood, they get stiff joints (which inhibits climbing) and hardened foot pads (which prevents sticking to vertical surfaces). One of the researchers, noticing that aged roaches seem to have lost their ability to escape from predators, hypothesized that the loss was brain-based; he tested the hypothesis by removing the roach's head (and, thus, brain), and sure enough, the roach once again was able to flee like a youngster.
[Case Western Reserve University News, reporting on a Journal of Experimental Biology article, 1-15-04]