More about finger length

Let's take a closer look at that last post. The person who wrote the UPI piece didn't interpret the original paper the same way I did. The finger measurement they were using was the ratio between the length of the index finger (2D) and the ring finger (4D).

Since as early as the 19th century(1), people have noticed that men tend to have a lower 2D:4D ratio than women. Since then the ratio has been linked to a variety of sexual, psychological, and behavioral traits. The number tends to be lower for men, for people with greater athletic prowess, assertive women, engineers, mathematicians, and lesbians. So they call a lower number a "masculinized" 2D:4D ratio.

But it's different in mice. Mice with a HIGHER ratio are more aggressive, more likely to bite when handled, and have a higher daily level of activity.

In the study cited here, the investigators selectively bred mice to be more active; they selected the mice that liked to run in their wheels more and bred them to each other. Then they measured their fingers. Voila. They had a HIGHER 2D:4D ratio.

So does this mean that finger length has any biological implication for behavior, physical prowess, or sexuality? Here's what the authors said:

"Given the many factors that have the ability to affect digit ratio, it is clearly more complicated than a simple testosterone-driven manliness metric."

I couldn't have said it better. Yeah, there might be some hormonal thing going on, but as it stands, it's no more scientific than trying to guess what's going on in a person's head by mapping the bumps on the skull.

(1) Anthropological Notes on the Human Hand Frank Baker

American Anthropologist Jan 1888, Vol. 1, No. 1: 51–76.

How long are your fingers?

From UPI.com:

Finger length linked to

desire to exercise

EDMONTON, Alberta, Sept. 17 (UPI) -- Canadian and U.S. researchers say there is a direct correlation between the length of fingers and being motivated to hit the gym.

Researchers at the University of Alberta and University of California-Riverside, who conducted a study using 1,000 white mice, said the findings seem to support a stronger connection between digit length, voluntary exercise and high levels of prenatal stress hormones -- indicated by the difference in activity level between the control mice and the selectively bred, active mice.

The study, published in the journal PLoS ONE, suggests prenatal stress, rather than prenatal testosterone levels in the womb, forms a component of the inherent desire for physical activity.

"The research shows a link, or relationship, between the brain, behavior and personality traits and the shape of the hand," lead researcher Peter Hurd of the University of Alberta said in a statement. "It opens the door to the notion that aspects of one's personality, in this case the desire to exercise, are fixed very early in life.

Here's the actual paper, from which the above photo was lifted.

The language of adolescent mice

Different inbred strains of laboratory mice interact differently, suggesting a role for genetics in social behavior.

They may also speak a different language.

This paper examined behavioral differences between two common strains of mice during adolescence. In the wild, when young mice leave their mothers and head off on their own, they may do so in groups, and the social interactions between individuals in those groups may have survival advantages. The young mice also need to establish territory and find mates. In the study, adolescent C57BL/6 mice had more social interactions than age-matched BALB/c mice. The differences became less pronounced as the mice matured.

The investigators analyzed the mouse vocalizations, even the ones too high for the human ear to detect. (Remember the singing mice?). Vocalization was correlated with social interaction; the socially interactive C57BL/6 mice were more talkative than their BALB/c peers. The C57BL/6 mice also tended to make shorter, higher pitched vocalizations than BALB/c mice.

The investigators found modulations in pitch within each vocalization that reminded me of my disastrous attempt to learn to speak Chinese with all its inflections; upward, downward, complex.



This study also found that the two strains differed in the ways they modulated their vocalizations. For example, BALB/c mice were more likely to use upward modulation and C57BL/6 mice were more likely to use downward modulation.

I wonder if everything the BALB/c mice had to say sounded like a question.

Upcoming events

Now that the Olympics are over, I thought some of my loyal readers would be interested in competitive events to be held in the near future:

6 September: London Championship Show, Rivermead Leisure Centre

20 September: Annual Cup Show, St Christophers Church Hall

12 October: Peterborough Agricultural Show

25 October: Swindon Mouse Club, Hermitage Village Hall

1 November: Greater Manchester Mouse Club, Methodist Church

22 November: Yorkshire Mouse Club

21 December: Stafford Poultry Show

These events are under sponsorship of the National Mouse Club. Although the phenomenon peaked in the Victorian era, fancy mice are alive and squeaking. As I have posted previously, fancy mice--mice bred for mouse beauty pageants--were instrumental in the introduction of mice into biomedical research. In fact, mice of the common breed C57BL/6 are direct descendants of fancy mouse number 57.

I'd love to attend the December 21 show, if only to see why the National Mouse Club would sponsor a poultry show.

Mouse Mouse

When I'm cruising the web for blog fodder, I'm often confronted with the "other kind" of mouse. You know, the kind that makes your cursor move around. Well, here's how to marry the two concepts. Mind you, it's a little gruesome.

Really big rodents

OK, it's not even September yet, and the scrabbling in the walls has started. Maybe the mice know something we don't know about an early winter.

At least it's not rats. I remember seeing some really big rodents hanging around the dining hall dumpsters in college. I'd hate to have those scrabbling in the walls.

If you want to see some really really big rodents, you need to get away from mice and rats and look at capybaras, which can weigh up to 140 pounds. Imagine the holes this guy could chew in your walls:


For some really really really big rodents, we can look to the fossil record and find Josephoartigasia monesi, which had a 21-inch skull and could have weighed as much as 2,200 pounds:

I don't think these things would scrabble in the walls. It would probably be more like this:

Guns don't kill people...

From foxnews.com:

Woman Shoots Herself While Trying to Kill Mice

POTTER VALLEY, Calif. — A Mendocino County woman who was trying to kill mice in her trailer with a gun ended up shooting herself and another person.

The 43-year-old woman pulled out her .44-caliber Magnum revolver after she saw the mice scurrying across the floor of her trailer on Highway 20 in Potter Valley, sheriff's officials said.

But she accidentally dropped the gun, which went off as it struck the floor. The bullet went through the woman's kneecap, bounced off the keys sitting on the belt loop of a 42-year-old man in the trailer and grazed the man's groin before ending up in his coin pocket.

Authorities did not release the shooting victims' names.

The mice escaped the shooting unharmed.