Jessica Wynn
👤 SpeakerAppearances Over Time
Podcast Appearances
Those who suck their right thumb in the womb usually grow up right-handed.
Those who go for the left thumb, left-handed.
It sticks.
I didn't even realize fetuses suck their thumb in the womb.
Yeah, they do.
I know, they do.
Well, we just see it really early.
But that's the big question.
Nature and nurture are both going on in the womb, too.
So the brain starts picking sides before you even have thumbs, actually.
Scientists have been chasing the genetic side of this for decades.
I mean, genetics is definitely a part of it, but it's not the only thing pulling the strings.
It's many small genetic effects, plus the prenatal environment, and then some good old-fashioned randomness.
No, not at all.
Children of left handed parents are more likely to be left handed, but the probability is still pretty low.
And most children still turn out right handed.
So heredity has a genetic component.
So it does raise the odds, but it doesn't seal the deal.
Like, are your kids left handed?
Yeah, it's rare.