Handedness: Environment or Genetics? …and other news

Around the world, only 5 to 20 percent of the population is left-handed.  But why?

 

Handedness: Environment or Genetics? - Myth Busting MommyA 2012 study suggested that societies that had more shared tools have people with the same hand dominance.  It makes sense, right?  If you only have right-handed tools to work with, you’d better learn to be right-handed or risk injury.

Another study thought handedness came into play for better combat.  Those who were left-handed, it was determined, had a better chance of winning a fight.  Although perhaps that is because most people are expecting an attack from the right.

And then there is the theory of genes.  Some scientists thought genes were definitively the way that we get our hand dominance.  However, some identical twins favor different hands.

Huh.  So, why are some people left handed?

Well, it looks like it’s a combination of environmental factors and genetics.  And a new study has begun to find some of the genes that are most responsible for it.

A gene called PCSK6 is known to provide the information as to where internal organs should be in the body.  People with mutations to this gene can have conditions where their organs are reversed in their body (situs inversus), or basically have two left sides to their body and multiple spleens (left-handed isomerism).

But it was also found that this gene can affect how the brain works, specifically when it comes to hand dominance.

There’s still more research to do, but it gives scientists a good place to start.

 

Pretty cool, huh?  Here are some other interesting stories that came about this week…

 

1.  Babies know animals should have guts.  In this study, it was found that infants expect things that move to have organs inside.  When objects were made to appear to be alive and then were broken apart, babies showed surprise that the objects were hollow.

 

2.  A mom posted on her blog about how teenage girls should cover up.  This created a slew of responses, from pats on the back to comments about “slut shaming”.  I read many of the responses and I liked this one because while the author disagrees, she keeps it civil.

 

3.  A study found that kids can’t properly assess risks.  No wonder they don’t listen when you tell them to “stop doing that or you’ll get hurt”!  :)

 

4.  Some airlines are making kid-free quiet zones in their planes.  Good idea or insulting?  Let me know in the comments!

 

5.  More than one fifth of parents think it’s okay to skip the kid’s seatbelt.  Interestingly, the wealthier the parent, the more likely they are to say that kids not wearing a seatbelt sometimes is okay.

 

Looking for inspiration and information?  Check out the news, crafts, and activities I’ve posted on Pinterest!

 

Photo courtesy of Heather Katsoulis on flickr.com.

8 Comments on Handedness: Environment or Genetics? …and other news

  1. Kate
    September 16, 2013 at 12:01 pm (11 months ago)

    That is really interesting! I will have to look into this a bit more as I am left handed (I also have 1 Aunt and 1 Cousin who are lefties), my hubby is a lefty in terms of writing and using eating utensils (only lefty in his immediate family that I know of) yet he does everything else right handed. Our daughter is right handed in terms of eating and writing, but does everything else including sports left handed! So interesting. This is the second article I’ve seen on “handedness” today so I am really going to start looking into this! Found you on Pinterest, now following you on all your social media, such great articles!
    Kate recently posted…Menu Plan Monday #23My Profile

    Reply
    • Amber Schultz
      September 16, 2013 at 12:36 pm (11 months ago)

      I’m glad you enjoyed it. I find it really interesting as well. I’m right handed but I can only do left-handed cartwheels! So strange. Thanks for following!

      Reply
  2. Anonymous
    September 16, 2013 at 4:05 pm (11 months ago)

    Great post! I tweeted it out, as well!

    ~Bonnie a.k.a. LadyBLogger http://ladyblogger.net

    Reply
  3. Anonymous
    September 17, 2013 at 11:46 am (11 months ago)

    This was so interesting! I am left handed- it was nice catching up on where my hand dominance comes from.

    Reply
  4. Stephanie from Burbs to the Boonies
    September 17, 2013 at 1:51 pm (11 months ago)

    #3 makes total sense! ACK! #4 seems silly. Are we all to be insulated from everything, even children now? How can a plane ever be “quiet”? Doesn’t make sense to me. And #5 seems scary to me. There are safety things I just will not compromise. And if a parent makes it important, the kid will pick up on it as important. If parents let it slide, kids will too as they grow up.
    Stephanie from Burbs to the Boonies recently posted…Small Town Tuesday: Country cook-outMy Profile

    Reply
    • Amber Schultz
      September 17, 2013 at 2:00 pm (11 months ago)

      The seatbelt thing really scared me too. I didn’t know that so many parents didn’t think it was a big deal. And that’s a great point about being a safety role model for your kids!

      Reply
      • Stephanie from Burbs to the Boonies
        September 17, 2013 at 2:09 pm (11 months ago)

        I’m always amazed and humbled how my kid looks to me as the answer to everything. ACK! Such responsibility. He believes every single word I say and every single thing I do (of course he’s only 7, ha! That may change.). It sure holds me accountable, and if I veer off course he is not shy about calling me on it.
        Stephanie from Burbs to the Boonies recently posted…Small Town Tuesday: Country cook-outMy Profile

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