28 Sep 2003 @ 00:33, by Raymond Powers
Of cats and rats -- a tale that's a brain-teaser
COMMENTARY: RAMSEY CAMPBELL
September 8, 2003
Cats are more interesting than dogs because felines have that dangerous edge to their behavior that canines can never match.
Dogs can run after balls, fetch a newspaper, play stupid games and follow a few spoken commands. Like television's Lassie, they have a reputation for selflessness and heroism.
Cats, however, have a much darker side.
Sometimes, though, it comes out as kind of cute.
Like the feline fur ball I had as a kid that delighted in shimmying backward down our chimney and out through the fireplace on snowy Indiana winter nights. Black soot covered our family room after her little adventures.
What got her into sliding down our chimney, like a kid on a Disney ride, is anyone's guess. But I can't imagine a dog doing anything as remotely interesting -- or as singularly bizarre.
Felines are forever stereotyped as evil by the two sinister Siamese cats in Lady and The Tramp.
And there is more truth in that ominous image than most cat lovers will admit.
My 20-pound black and white cat -- dubbed Kalibushka, a Russian name that can be loosely translated as Tub of Lard -- is normally good-natured.
She rarely moves except to chow down, making her home in the newspaper recycling bin I keep in the garage.
But at night she'll sneak out for a few minutes and come back with a prize. She has the habit of presenting these nightly trophies to me by the back porch.
Somehow, in spite of her obesity, she manages to out-waddle a surprising number of fast-running rodents in short order.
I don't mind her nightly hunting routine; I can't say I'm displeased she is keeping down the rat and mouse population in the neighborhood.
A few weeks ago, however, I started to notice the rats she had caught have been missing something -- their brains.
With the exception of a few teeth marks, the bodies of the rats are generally unmarked. But the skulls are split open and the brains appeared to have been neatly sucked out.
Yucky.
Why would a perfectly normal -- although admittedly overfed -- cat suddenly develop a taste for rat brains?
I did a little research, and it turns out there may be a reason for her sudden hunting prowess and passion for rat brains.
I ran across a BBC science article about a week ago that shed some light on the situation.
Scientists have discovered a one-celled protozoan parasite called Toxoplasma gondii that frequently lives in the brains of wild brown rats. It is a normally harmless parasite commonly found in most mammals, including man.
But T. gondii can only reproduce in the guts of cats.
Researchers at the University of Oxford in the past couple of years have been studying the parasite and now have found it appears to be influencing the behavior of rats.
Scientists say it makes infected rats unafraid of cats, their natural enemy.
But the Oxford researchers found that when infected, normally super-cautious rats not only are significantly less fearful of cats, but they also are actually drawn to them.
No one knows how it happens, but they do know why.
The parasites need to be eaten by cats in order to get into their digestive system and reproduce. Somehow, they are changing the behavior of rats to make that more likely to happen.
It appears to be a rare case of microscopic parasites manipulating the behavior of a mammal host.
The question remains whether T. gondii can, in addition to rats, influence cat behavior or even our own. Researchers now are looking into that issue as well.
I've seen Alien -- no one needs to draw me a picture of what may be going on.
I can't really blame my overweight cat if rats in the neighborhood suddenly want to commit suicide in front of her.
And if she wants to wolf down rat brains like candy corn, that also is fine with me.
But I am disturbed by a change in Kalibushka's behavior in the past couple of days.
She is now eating just the rat bodies, leaving the heads and brains intact by the back porch.
And I'm very afraid she's leaving them for me.
|
|