Rat exterminators in Montego Bay were shocked when they encountered a rat having sex with a cat behind a well-known fast food store in the second city.
“The rat was giving the cat a hard backas, we were shocked, I am just sorry I never caught the whole thing on my phone,” the rat exterminator said.
Scientists have scrambled to explain the attraction that rats feel for cats
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Sometimes it’s hard to tell the difference between danger and sex appeal, at least for rats infected with a parasite that twists ancient rat instincts to its own advantage.
The parasite, a common single-celled organism called Toxoplasma gondii, infects all sorts of animals, including rats, in which it causes a strange transformation.
“For obvious reasons, rats normally avoid cats. In the presence of cat urine they become very timid — unless they’re infected with Toxoplasma. Research over the past 10 years has shown that infected rats drop their normal fearful “freezing” response, and instead go exploring. They even approach the cat smell,” one environmental expert said.
It’s a vicious cycle because Toxoplasma reproduces sexually only in cats. Parasite infects rat. Cat eats rat. Parasite reproduces.
The parasite can also infect all sorts of other animals, including humans, in which it causes toxoplasmosis — one of many good reasons to avoid contact with cat droppings. But outside of cats, its reproductive cycle cannot be completed.
If this puppet-master behavior were not strange enough, scientists have now found out how the parasite may change rat behavior.
Toxoplasma infection activates a part of the rat’s brain normally engaged in sexual attraction. The smell of cat urine revs up this set of neurons like the presence of a sexually receptive female rat normally would.
The neurons that trigger the rat’s normal “freezing” reaction to cats continue to fire. But their message may get swamped by the overactive sexual attraction signaling, the researchers suspect.
“Thousands of scientists are trying to figure out how to tamp down anxiety, and this tiny parasite has already figured it out,” said Robert Sapolsky, a Stanford University neuroscientist and co-author of a paper reporting the discovery in the journal PLoS One.
