There was once this eminent scientist conducting research into how fleas jump.
After carefully selecting a candidate flea, the scientist instructed the flea to jump and it jumped. Next the scientist pulled a leg off the flea and again instructed it to jump, and the flea dutifully jumped. The scientist pulled another leg off the hapless flea and again the flea jumped on command. The scientist repeated this bizarre experiment another three times until only one leg was left. The scientist pulled off the remaining leg and commanded the flea to jump, but the wretched insect just lay there.
“See”, the scientist concluded, “when you pull all the legs off a flea they go deaf!”
(Disclaimer: No fleas were harmed in the making of this joke)
This joke was told by a friend, frustrated at the seemingly endless parade of research, published in the popular media, which is soon after publication contradicted by yet more new research.