Left-handedness

Left-handedness
If someone is moving clumsily,
we often say he or she has two left feet.
But what does our left side have to do with being clumsy?
Is one side actually better than the other?
Left-handed people have faced prejudice in many cultures.
Muslims, Buddhists and mediaeval Christians
all considered left-handedness a bad thing.
There are still cultures that show this bias.
The word for “right”, for example,
is associated in various European languages
with goodness and propriety
and even with law and justice in some languages.
The low number of left-handed people
may also play a role in this bias.
Only about 10% of the population is left-handed.
And being left-handed is not that easy
because most tools and equipment are designed
for right-handed people.
These include tin openers, scissors and circular saws.
Animals have a dominant side too,
but their chance of developing a dominant left or right side
is 50-50.
But what causes the majority of people
to have a dominant right side?
The answer lies in the way the motor pathways
have developed in the nervous system.
The movement of the left hand is controlled
by the right hemisphere of the brain,
while that of the right hand is controlled by the left one.
That side of the brain also regulates writing,
speech, language and logic.
Since these abilities played a decisive role in humans
in the course of evolution,
right-handedness also became dominant.