Do you read your horoscope? Evidently the month you were born is supposed to influence your personality and fortune. I’m a Pisces, so I’m supposed to be compassionate, empathetic, sensitive and dreamy.

As a proud skeptic, I don’t put any stock in astrology, but I may have prematurely dismissed the idea that one’s birth month is influential. It turns out that when you were born has a big effect on your eyesight.

In a study published this week, researchers at Tel Aviv University looked at data on 300,000 Israeli youths and correlated their months of birth with incidences of nearsightedness. Individuals born in the summer months were far more likely to need glasses than those born in the winter — those with birthdays in June and July had a 24 percent greater chance of nearsightedness than those born in December and January.

The correlation is all about sunlight. Previously, scientists studying nearsighted chickens realized that their eyeballs lengthened when exposed to prolonged illumination. (Nearsighted eyes are longer than normal.) Weirdly, this lengthening process seems to be under the control of melatonin, the hormone that sets the body’s circadian rhythms. According to the Tel Aviv scientists, more hours of sunlight means less melatonin production, which leads to a longer, nearsighted eye. So, if you were born in the summer, you might want to start looking at eyeglass frames now.

From ophthalmology to psychology: Scientists at Duke University have bred mice with a rodent version of obsessive-compulsive disorder. The obsessive-compulsive mice cower in the corners of their cages and groom their faces raw. A press release photo shows a mouse whose compulsive grooming erased half the fur on its face, leaving bald and bloody patches. The mice are similar to obsessive-compulsive humans, who often show pathological grooming behavior, including hair-pulling, skin-picking and excessive hand-washing.

The discovery of the obsessive-compulsive mice was a lucky accident — nobody was looking for mentally ill rodents. The Duke researchers’ original intent was to do basic research into how individual brain cells communicate. They used genetic engineering to knockout a neurotransmitter called SAPAP3, and the resulting mice showed up with sores and bald patches. Videotaping confirmed these wounds were self-inflicted, and the researchers realized they had discovered a mouse model for OCD.

Like humans with OCD, the obsessive-compulsive mice got better when given a class of antidepressants called SSRIs. The rodents could also provide insight into drugs beyond SSRIs. If faulty SAPAP3 has a role in human OCD, the neurotransmitter could be a novel drug target for the 2.2 million Americans who suffer from this debilitating disorder.

X-rated news from the insect world: It turns out female beetles may have sex because they’re thirsty. University of Exeter biologists studied Callosobruchus maculatus, a small brown beetle that is a serious agricultural pest. The male of the species has an enormous volume of ejaculate, accounting for up to 10 percent of its body weight. (Imagine a human male with 20 lbs of semen!) There’s a reason male C. maculatus climax so copiously — it’s their “nuptial gift” to females, who can absorb water from the ejaculate left in their reproductive tract after mating.

Given this information, researchers began to wonder if female C. maculatus might have sex to remedy dehydration. To test the idea, some female beetles were give unlimited access to water, while others prevented from getting any water at all. The water-starved females mated 40 percent more often than females who had plenty of access to water.

The research into dehydrated beetle sex is the weirdest piece of science news I’ve seen all summer. I’m imaging a beetle version of “Maxim”, with tips for scoring with the ladies. “Take her out to dinner, and don’t buy her anything to drink! She’ll be so thirsty she won’t be able to keep her hands off you!” Hopefully no human males will take ideas from C. maculatus.