The African Crested Rat has figured out a way to kill off the jackals and lions who try to prey on it. This little critter is 21 inches from head to tail, but no one and nothing can afford to take a bite out of it. Between its specially adapted physiology and peculiar behavior, this rat can take out pretty much any animal. It uses a potent plant poison to fend off enemies.
Specifically, the rat uses acokanthera, the 'poison-arrow plant.' Guess how that plant got its name.
This rat has a physiological adaptation that allows it to turn the plant's toxins into tiny bio-weapons. Scientists observed the rats chewing on the plant's branches, then smearing their saliva on their upper legs. A little closer observation revealed that under the rats regular fur were porous bristles. A cross-section of those bristles showed an absorbant middle section that sucked in and stored the poison.
When the rat is threatened, it flips back its regular fur and offers its leg to its attacker. One bite releases toxins into the attacker's mouth and kills it, leaving the rat to limp off and fight another day. Since the rat obviously has not had apothecary or fighter's training, this survival strategy demonstrates several different behaviors coming together with a physical adaptation. The rat had to learn to handle the poison and use a winning battle strategy, while developing the specially adapted hairs. What you've got here are physical and behavioral evolution, coming together to take out a lion. Not bad, for a rat.
Via New Scientist.