what is the benefit of having a dominant hand/leg as compared to having equally skilled limbs?
In: Biology
Instead of thinking of it as if being good at both hands is the default, and asking why one hand is worse, it helps to think of it as if being BAD at both hands is the default, and then asking why it’s good enough to be good at just one hand.
The quality of human hand dexterity is *amazing* and takes *work* and processing power. The difference between having zero good hands and one is enormous. The difference between having one good hand and having two good hands is less so. You get less “bang for your buck” putting the same effort into having a second good hand than you got for having at least one good hand. One good hand plus one merely okay hand seems to be a “good enough” solution.
I think the more interesting ELI5 question is, if our arms have mirrored symmetry, then why is picking the right hand to be the one all that effort goes into so much more common than picking the left?
The existence of left-handed people proves it’s not really any detriment to be left-handed (except culturally because right-handedness is such a common assumption when making things).
Is it nature, or nurture, that makes most of humanity right-handed? I’d have assumed nurture, except that doesn’t explain why so many different cultures became right-hand dominant independently before they contacted each other.
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