Gay hands

"It's a mix of biology and environment." Which is scientific speak for: "We still have no clue."

The dream of finding a simple "gay gene" is pretty much dead. These chemical messengers, particularly testosterone, cause chain reactions in the body, spurring the growth of the genitals, encouraging and inhibiting growth in brain regions and causing changes in the fingers.

In women, these fingers are usually the same length or the index digit is just a bit longer.

Digits are subtly affected by testosterone and estrogen produced in the womb by the fetus (not by the mother). Because of the influx of sex hormones at this prenatal stage, men tend to have ring fingers that are slightly longer than their index fingers.

Real scientific progress is rarely as tidy as headlines make it seem.

The "gay hands" study and the broader search for a gay gene remind us that sometimes, science is just politics wearing a lab coat. But the differences between the sexes aren't all that interesting to biologists. It wasn’t.

This finger-length study was just one part of a frenzied hunt for the elusive "gay gene." But why were scientists so desperate to find a biological basis for homosexuality?

Far from it. When the answers seem too clean or too convenient, that's when our alarm bells should start ringing.

So the next time you hear about a study that perfectly proves, or disproves, your point on a contentious issue, take a step back. Unsurprisingly, no one could replicate its results.

One study would find a link between testosterone levels and sexual orientation, only to be debunked by another larger study. It's full of dead ends, contradictions, and unexpected results. To be certain, take a ruler and measure from the bottom crease of each finger to the tip.

The measurements tell you something about the environment of your mother's womb just weeks after your conception, a time when your fingers, and more importantly, your brain, were developing.

Girls with masculine-type finger ratios tend to have higher hyperactivity scores and more problems relating to their peers than do other girls.

This "groundbreaking" discovery splashed across media headlines, seeming like a revolutionary breakthrough in understanding human sexuality. The [sexuality indicators] are most certainly there, but they're not strong enough to allow us to make predictions."