I couldn't pass this one up, it's too delicious. New Zealand scientists tried to discover why rats are so difficult to eradicate by dumping a single rat on a deserted island then trying to catch it. Him, I should say, because the darn rat showed almost human intelligence. He evaded traps, baits, and other nasties for four months, then was finally found on another island 400 meters from the island he was dropped on. On top of it, the rat had a radio collar!
"After 10 weeks on the island the rodent decided it had had enough. It swam 400 meters, the longest distance recorded for a rat across open sea, to another rat-free island where it was eventually captured in a trap baited with penguin meat several weeks later."Huh. Talk about survival of the fittest.