MOODY FINGERS

Is your ring finger longer than your index finger? If you’re a man, it may indicate you’re more prone to depression.

The same genes control the prenatal development of fingers and gonads. Long fingers in men seem to indicate exposure to high fetal testosterone levels. Since high prenatal testosterone may predispose men to psychological ailments, a biologist at the University of Liverpool measured finger lengths and screened for depression. The men with the shortest ring fingers were least likely to be depressed.

No such correlation was found in women.

WHY CANT YOU SEE I’M ANGRY?

Guys, she may be hopping mad. And you, being guys, just haven’t got a clue.

Psychology grad student Lisa Goos of Toronto showed college students photos of male and female faces displaying four emotions: anger, fear, disgust, or sadness. While the men correctly identified anger in other men about 40 percent of the time, they had a harder time identifying anger in women.

Goos believes this is a natural result of evolution, which dictates that what’s important for survival will be perpetuated. Men learn to recognize anger in other men because an angry man could pose a physical threat. But an angry woman is not something to worry about.

Oh yeah?

MORE ON THOSE CANNIBALS

Last issue, I wrote about the biochemical evidence that cannibalism existed among tribes of the American southwest. Now comes more evidence that cannibalism is an ancient and not all that uncommon practice.

In the Fiji Islands, Berkeley student David DeGusta analyzed human bones collected from a 2000-year-old refuse heap. Based on the patterns of breaks, burns, and cut marks, he concluded that cannibalism was indeed practiced among the ancient Fijian Islanders.

The practice of eating your fellow hominids may extend to the Neanderthals as well. A French and American team found that 100,000-year-old Neanderthal remains in France bear the signs of the same butchery techniques that were used on animals. Marks on skulls indicate that muscles were filleted from the faces of two young victims, that the tongue was sliced out of one, and that leg bones were smashed to get at the marrow and braincases broken open to get at brain matter. One thing bone had had muscles sliced away. Cut marks on a collar bone show that the arm of one victim was disarticulated at the shoulder.

The bones show no signs of burning. This suggests the flesh was eaten raw.

What is fascinating is that Neanderthals were also capable of ceremonial burials, treating some of their dead with obvious reverence. Why were different corpses accorded such disparate treatment? Were the victims of cannibalism enemies? Or were they eaten out of desperation and famine?

Anthropologist Fred H. Smith of Northern Illinois University believes this varied treatment of the dead demonstrates cultural complexity. “When you see some Neanderthals practicing intentional burial and others practicing cannibalism, that is a clear indication of behavior that is multidimensional — a pattern that mirrors the behavior of more modern people.”

BEETLE JUICE

Here’s a defense mechanism that’s new and different: shoot boiling vapors out your rear end. That’s what the Bombardier Beetle does. When attacked, it fights back by firing a chemical spray of a caustic, foul-smelling gas. The beetle can fire up to a dozen times, and each spurt produces an audible pop. The spray itself can blast an enemy as far as two inches away.

The spray is produced by the mixing of two different chemicals which the beetle stores in separate glandular compartments. One compartment contains a solution of hydroquinone and hydrogen peroxide, and the other contains a mixture of enzymes. When harrassed, the beetle mixes the contents of these two compartments. A chemical reaction takes place which produces so much heat that the vapor actually reaches the boiling point.

Then all the beetle has to do is point its rear end at the enemy and fire away.

WAS DRACULA RABID?

(from Hippocrates, March 1999)

Dr. Juan Gomez-Alonso, a Spanish neurologist, happened to be watching the film “Dracula” when he had a sudden flash of insight: could the source of vampire legends be rooted in the classic signs of rabies infection?

Consider what happens to a patient infected with rabies. Aggressiveness and hypersexuality are common. Twenty-five percent are prone to biting others. Because they’re hypersensitive to all stimuli, rabies victims often avoid light, mirrors, and strong odors such as garlic or onions. Spasms of the facial muscles produce bared teeth, and they’ll often froth at the mouth. Insomnia and night wandering are common.

Dr. Gomez-Alonso also notes that during the years 1721-28, a major rabies epidemic among dogs and wolves broke out in Hungary — precisely the time and place when the first vampire legends began.

I THINK I’D RATHER SWIM WITH PIRANHAS

Oh, the mighty Amazon, home to a host of scary critters. Thanks to Hollywood, we’ve all been acquainted with the horrors of anacondas, jaguars, and piranhas. But the scariest creature of them all could be a tiny fish that’s so translucent, you may not even realize it’s there…

Until you start screaming in pain.

The candiru (Vandellia cirrhosa), only an inch long and needle thin, is the smallest species of catfish. Like other catfish, it has sharp spines on its dorsal and pectoral fins. It’s adapted for a parasitic life in the gills and cloacae of bigger fish, and it finds its way into a new host by following the scent of uric acid, which fish emit from their gills. Then it uses its spines to plant itself into its new home.

Uric acid, by the way, happens to be a component of human urine. (You can probably guess where this is headed.)

So there you are, the intrepid toursit on the banks of the Amazon River, wading in for a swim. Maybe you had a little too much to drink and you also need to pee. You figure you might as well do it while you’re in the water. So you glide right in and let loose.

Along comes a candiru. Sniffing urine, it darts toward the source, thinking it’s heading into a host fish. Instead it’s swimming straight up your urethra, where it plants itself by raising its gill covers and driving its spines into your exquisitely sensitive tissues.

This is where the screaming part comes in.

Removal is said to be so difficult, and the pain so excruciating, that South American natives have been known to amputate the penis just to end the ordeal.

Lest women think this is a problem just for the guys, candiru have been known to burrow inside any unprotected orifice, including the anus, vagina, and nose.

There’s plenty of screaming to go around.

A TUMOR WITH TEETH

CASE HISTORY: “Mary,” a 24-year-old woman, visits her gynecologist with a chief complaint of lower abdominal “fullness.” She describes it as a dull aching pain in her pelvic region and lower back. Intercourse is painful, and her menstrual periods have recently been irregular.

On pelvic exam, the physician detects a right ovarian mass, about the size of a hen’s egg. Pelvic ultrasound shows that the tumor has both solid and liquid components, with a dense spot of calcified matter.

An abdominal x-ray reveals a startling finding: Inside the tumor is a human tooth.

Perhaps the most bizarre of human tumors is the ovarian dermoid cyst, or mature teratoma. Usually found in young women, these weird tumors are not at all uncomoon, and account for about twenty percent of all ovarian tumors.

What makes dermoid cysts so fascinating (and truly creepy) is the fact they arise from the ovary’s germ cells — cells which are capable of developing into a complete fetus. A germ cell is the forerunner to all human tissues, and thus has the potential to become any organ or structure in the body. But instead of growing into a complete fetus, these cells form a disorganized mishmash of human tissues.

The cysts may contain clumps of hair, bone, skin, or sweat glands. Often there are pockets of sebum — a thick greasy fluid secreted by the skin’s sebaceous glands. Some tumors may even contain recognizable teeth!

The good news is, 99 percent of dermoid cysts are non-cancerous. Often they do not even cause symptoms and are first detected on routine pelvic examination.

The cure? surgical removal. But while some patients have been known to bring home their gallstones in a jar, this is one surgical souvenir you probably don’t want to display on the mantlepiece.

MORE ON FIGHTING FAT

Don’t tell your kids to stop fidgeting. It’s good for them.

Fidgeting may, in fact, be the key to why some people simply don’t gain weight, no matter how much they eat. At the Mayo Clinic, sixteen volunteers each pigged out on an extra 1,000 calories a day for two months. All were limited to minimal exercise. They gained an average of ten pounds, but there was a range from two to sixteen pounds. What accounted for the difference between subjects?

How much they fidgeted. On average, fidgeting burned up a third of the extra calories. Those who gained the least fidgeted the most.

Keep tapping those feet.

BLAME THAT FLAB

Dieting got you down? Just can’t lose that weight? It may not be YOUR FAULT. Biologists have identified a virus that causes animals to get fat. When the virus AD36 was injected into chickens and mice, their body fat ballooned. Could this explain human obesity?

The scientists tested 154 people for the presence of antibodies to this virus, which would indicate a prior infection. 15 percent of those who were obese had the antibodies. None of the lean subjects did.

Five other viruses besides AD36 have also been shown to cause obesity. Who knows — some day there may be a vaccine against getting fat.

BACH AS BRAIN FOOD

Listening to classical music causes a surge in blood flow to the brain. That’s what neuroscientists discovered when they ran positron emission tomography (PET) scans on test subjects as they listened to Bach. The increased blood flow was especially marked in the cerebellum, which controls balance and coordination. Music also improves function in other parts of the brain. A study of female college students found that those who studied music as children had a significantly better memory for recalling word lists than those with no music training.

But does music produce a measurable anatomical difference in the brain?

Doctors at Beth Israel Hospital in Boston say so. They studied cerebellar volume in ninety musicians and nonmusicians. The cerebella of musicians was five percent larger than those of nonmusicians — leading one to conclude that music stimulated extra nerve growth.

Guess what? Mom was right about practicing that piano.