Left-Handedness Common In Ice Age

BBC ^ | 2-14-2004 | Dr David Whitehouse

[blam]

Left-handedness common in Ice Age

By Dr David Whitehouse
BBC News Online science editor

A right-hand print signifys left-handedness

The fraction of left-handed people today is about the same as it was during the Ice Age, according to data from prehistoric handprints. They were found in caves painted during the Upper Palaeolithic period, between 30,000 and 10,000 years ago.

Left-handedness may have conferred prehistoric man advantages, such as in combat, say the researchers.

The research is published in the February issue of the journal Biology Letters.

Evolutionary advantages

When Stone Age man produced their remarkable cave paintings they often left handprints on the walls produced by blowing pigments from one hand through a tube held by the other hand.

Charlotte Faurie and Michel Raymond at the University of Montpellier, France, deduced the prehistoric cave painters' handedness by spraying paint against cave walls to see which hand they pressed against the wall, and therefore did not use for drawing.

Looking at 507 handprints from 26 caves in France and Spain, they deduced that 23% of them were right-handed, which indicated that they were made by left-handers.

In the general population today about 12% are left-handed, though populations vary considerably, between 3 and 30%.

Because handedness has a genetic component the researchers wondered why the proportion of left-handers should have remained so constant over 30,000 years - the age of the oldest cave studied.

They suggest that because left-handedness is relatively rare it provides certain advantages over those who are right-handed, such as in solo and group fighting.

The researchers say their findings add to the evidence that the evolutionary forces that cause right- and left-handedness are independent of culture.

[Bluntpoint]

Too bad they did not have more left handed thermostats.

Maybe then they would not have frozen their asses off.

[blam]

GGG ping.

[farmfriend]

I mentioned the title of this thread to my husband, a lefty himself, and he said it was because you had to be smart to survive. According to him, more lefties are geniuses.

[farmfriend]

Gods, Graves, Glyphs
List for articles regarding early civilizations , life of all forms, - dinosaurs - etc.

Let me know if you wish to be added or removed from this ping list.

[Rabid Dog]

Well I'm left handed and the first thing I thought is maybe a buddy helped with the hand print.

Don't think they should be deducing that all handprints were a one-person operation. Could be two people involved so the whole conclusion could be erroneous.

[Tax Government]

I think the world is divided into two groups: 1) a strongly right-handed majority; and 2) a minority of more ambidextrous people of whom some become right- and other left-handed.

[cyborg]

I used to be able to write with both hands, now I just write with the right hand.

[Lucky Dog]

The researchers say their findings add to the evidence that the evolutionary forces that cause right- and left-handedness are independent of culture.

According to zoologists I have read, the relative dominance of one forelimb over another in species other than humans that show such characteristics is pretty evenly split between left and right.

Could a possible explanation for human right handedness lie in the simple requirements of physiology and social dining?

Toilet paper is a relatively recent development. In times past, and even today in the middle east and other places where toilet paper is not plentiful, people prefer the left hand for “hygiene” purposes and the right hand for eating from the communal dish. After all, no one wants to eat from a dish after some one else has just put a hand possibly “contaminated” with human waste into the dish.

Consequently, children were (and are in other areas of the world) trained in this protocol from the time they are “out of diapers.” Would it be unreasonable to expect that over thousands of years, a “trained” preference might not become converted, somehow, to genetic?

[farmfriend]

My son would fall into that last catagory but not my husband.

[Redcloak]

Left-handedness is only an advantage in combat when the majority of the population is right-handed. Thus if the majority of ice-age people were left-handed, the right-handed would have held the advantage in combat.

[ml/nj]

But evolution favored right-handedness because of the larger supply of right-handed golf clubs.

ML/NJ

[Carry_Okie]

Left-Handedness Common In Ice Age

There's something SINISTER about this!

[Tax Government]

I think ambidextrousness goes beyond use of the hand, into ways of thinking and body motion. (Once I had a dream that the two sides of my brain were fighting, and decided after a while they were really friends.)

[RockyMtnMan]

Most people are right handed because they were forced as a child to be a "righty". Many parents didn't want their children to be considered different and at a disadvantage because most products are or were made for right-handed people. At one point in time lefties were considered psychologically unstable and of less than average intelligence.

[luvbach1]

Would it be unreasonable to expect that over thousands of years, a “trained” preference might not become converted, somehow, to genetic?

Yes, unless the righthandedness resulted in "natural selection" of the righthanders by virtue of their superior survivability (thus it would not be "somehow"), the primary mechanism of evolution.

[Tax Government]

I have always wondered whether a foreign language could be learned efficiently by listening to a simultaneous translation, with the two languages heard in different sides of a headset. The outcome would probably be affected by headset polarity and brain dominance or handedness.

Someone eventually will test this, perhaps using a non-English TV broadcast where simultaneous English translation is available.

[Ophiucus]

"Looking at 507 handprints from 26 caves in France and Spain, they deduced that 23% of them were right-handed, which indicated that they were made by left-handers. "

A tenuous conclusion to make. Perhaps they made prints of the more important hand for posterity or ownership or whatever the reason for the print. I would argue that they used the hand that was more vital in their survival as the object of their print - the right.

[anymouse]

Us southpaws are the only people in our right minds. :)

Don't you just hate it that liberals give lefties a bad name. :)

[Ophiucus]

According to him, more lefties are geniuses.

While there isn't evidence of handedness and intelligence there is data on handedness and life expectancy. Lefties die earlier than righties.