Freak_NL 49 minutes ago

So why are us southpaws a rarity? The article and the linked research paper both point to bipedalism and bigger brains as the cause, and the paper vaguely seems to hint at selective pressures leading to the right hand getting favoured by the majority of the population, but why?

The question from the headline is excellent, if only it was actually answered.

  • scythe 20 minutes ago

    Here's my five minute lunchtime hypothesis: it's because the heart is on the left. As human behavior demanded increasing precision from the hands, being a little farther from the heartbeat was a slight advantage.

    • gpm 13 minutes ago

      If this was the case wouldn't it be easier to measure the pulse in peoples left wrists? Which doesn't seem to be a thing?

    • yawpitch 10 minutes ago

      Here’s my multiple years of anatomy classes response: the heart isn’t on the left. The aorta is, sure, but the vena cava is on the right. Also people with situs inversus (essentially all organs flipped laterally from “normal”) aren’t obviously more prone to left-handedness.

    • gherkinnn 6 minutes ago

      Wikipedia on Situs Inversus (visceral organs are mirrored, heart on the right, liver on left) [0], mentions mixed results regarding handedness. There would be a load of other confounding factors here and I know nothing about medicine.

      0 - https://en.wikipedia.org/wiki/Situs_inversus

hypnodrones 22 minutes ago

I would be interested in studies into impact of left hemisphere importantce on the right hand usage, possibly the more sophisticated and "logical" usage of our hands pressured it as well.

NickC25 23 minutes ago

What does it say for mixed-handed folks like myself (different skillsets per hand - in other words, throw and write with different hands)? What about cross-dominance (different body parts differ on dominant side - in other words, a right-handed person being left-foot dominant)?

I've been told that it's effectively a mental illness if discovered during childhood (as is ambidexterity). Yet I can't help but think that it is not a mental illness, but rather something else.

  • tejohnso 10 minutes ago

    In order to present it as a mental illness there would have to be some kind of negative effect, wouldn't there? These differences you mention don't stand out as harmful or even disadvantageous.

krater23 52 minutes ago

Didn't I understood the text or is the 'why' not really part of it? I expected more than a vague 'because it slightly existed and then hands are free to do things and brains got bigger'. I miss the point.

raggi 1 hour ago

Why are, Oxford.

  • Freak_NL 57 minutes ago

    'Everyone' is treated as singular (aside from 'everyone are' sounding completely wrong).

    • 3form 11 minutes ago

      I think that's the case for all the "every <noun>". "Every human is a person", for example. This would make sense, to put it in programming terms - the verb applies to an element in an array of people, not the array itself (which would be plural): for every single human, that human is a person.

  • darenr 54 minutes ago

    No, grammatically "everyone" is an indefinite pronoun. a single collective unit.

  • cwnyth 54 minutes ago

    Confidently incorrect.

  • stackghost 51 minutes ago

    Is that a British thing? Nobody in North America uses "everyone are"