How Humans Became (Mostly) Right-Handed

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No other placental mammal that we know of prefers one side of the body so consistently, not even our closest primate relatives. But being right-handed may have deep evolutionary roots in our lineage. And yet, being a leftie does appear to come with some unanticipated advantages.

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  1. Some commenters have pointed out that we say “after our lineage split with chimpanzees,” “members of our lineage after the split with chimpanzees,” and “after our split from chimpanzees” at various points in this episode. Just to clear things up, humans and our extinct relatives share a common ancestor with chimpanzees and their extinct relatives. After our lineage split from this common ancestor, we call our group “hominins.” Living chimpanzees also have their own separate evolutionary history since that shared common ancestor.

    • There are some very ignorant responses to D SP’s comment regarding “split from/split with”. He’s right… there is a substantial difference between the two and the people that are arguing the contrary need to “go back to English class”. And refrain from placing blame on Christians for the people bringing up PBS’ error.

    • @리주민 ancient languages were written right to left because most people are indeed right-handed and clay tablet and stone writing is cumbersome for right-handed people if it were written from left to right. As languages writing systems moved to parchment they could transition to left to right because that then prevented ink from smudging by the majority of right handed people.

    • Imagine believing something so stupid lmao

    • 6:07
      Proof that left handed people evolved from kangaroos, not apes 🦘🇦🇺😋

    • @리주민 I believe right handedness could have evolved for the sole purpose of facilitating eating with chopsticks 🥢 Lol

  2. Okay so if you’re a lefty then let me know if you have have this problem. I write on my left but the thing is my right hand is stronger then my left even though I’m a leftie like say when i throw a football I throw with my right instead of my left, same thing when I punch or kick. Why is my right more dominant than my left.

  3. Jason Scott Morris

    I think our handedness comes from our evolution with the use of tools. The heart is on the left side. If you predominately use a weapon on your right side, your heart is protected from danger, wild animal or other tool user

  4. Being left handed has the benefit of getting pencil lead all over your hand, it’s great 😊

  5. interesting!

  6. Me being a leftie and trying to write anything with a pen a not smudging it 🙁

  7. Thomson Pritchard-Torres

    Now How about ambidexterity?

  8. I use both hands.

  9. I’m left handed but play sports right-handed.

  10. What if a dominant hand evolved as 50/50 (left/right), with lefties having an advantage in fighting and righties in other non-violent motor skills. Then as civilisation evolved away from violence the percentage of lefties decreased to the percentage we see today. It may be beneficial to have a small percentage of fighters but overwhelmingly not advantageous for the greater population.

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