10/02/2007

How many people are lefties ?

Handedness link to people brain organization. Scientists estimate that 20% of children are born lefties. After they growing up, that rate reduce to about 11% in general population. In a recent investigation, 2 psychology professors from UK noticed that the rate of left-handedness plunged from natural 20% of children born around 1840 to a mere 3% of those born 50 years later (around 1890-1900).
The most likely reason that lefties dropped in numbers at the turn of the 20th century was possible strong social pressure brought about by universal education and the industrial revolution. These two factors would have forced lefties to change their handedness. During that period, left-handers may found it more difficult to find marriage partners, marrying later, and hence having fewer children so that fewer of the relevant genes went into the gene pool.

3 comments:

Amanda said...

My aunt is left handed and she has horror stories of how teachers in school used to beat her into right-handedness. Personally, I like looking at the way people use their left hands.

John said...

In the Book of Judges, there is a story of Ehud, a left-handed deliverer. An unlikely choice as the left hand in the Middle East is the hand of defilement. In Medieval times, lefthandedness was associated with witchcraft and so parents would go to great lengths to convert lefthanded tendencies--including breaking arms or hands.

eccentricvirgo said...

Interesting! I seem to always find only 10% is the statistical number of my fellow lefties! However, there were teachers who attempted to convert lefthanders to righthanders even in the 1980s - I had one and my mother had to fight the school. Believe it or not, this was a PUBLIC American school too!