Friday, February 20, 2015

Why Are Some People Left-Handed? - Ted-Ed Video

Brought to you by Allie


https://www.youtube.com/watch?v=TGLYcYCm2FM

29 comments:

Grace said...

This is an interesting thing to think about. I didn't really understand why the left-handed baseball player will be better than the right handed one, but it was interesting nonetheless. I think it was weird how the fetus position in the womb affects whether or not you will use an iron properly. (If you are right or left handed, irons were made for the right-handed) But I think it was cool how it said that identical twins have different dominant hands most of the time because I thought that identical twins were, well, pretty much identical. Who knew? I would really have liked the video to go into more detail because I didn't think they explained it enough, and the history references to the hunter-gatherers was pretty awesome. Plus, most of the US presidents were left-handed, Justin Bieber is left-handed, and a LOT (a LOT) of other celebrities/famous people/famed people were left-handed. This was pretty neat and I really hope that they will make more discoveries like this and we can learn more about more things similar to this.

Siji said...

It is very fascinating to me how two different true factors of left handedness contradict each other. One theory is that because of the great minority in lefties, they will have an advantage in competition. Natural selection would predict that they would gain an upper hand over the righties until they were the majority and their advantages were of much less importance. Similar to how for example brown bears lived in the arctic until one had a mutation and became a white bear. In the arctic, where the snow camouflages the white bear, it is easier for it to capture it's prey blended into the environment rather than the brown bear. Because of this, natural selection occurred until the white bear whipped out the brown bear's population by using its advantage until it is now the standard, the polar bear. In the case of lefties, natural selection should tell the same story, however it turns out not to because of a contradicting theory. This is that tools, weapons, and daily life has shaped itself to fit the vast majority, the righties, thus giving the lefties higher accident rates, and causing a bad fit in the norm of society.

Paisley said...

This is really a great article. First off, during the beginning of the video, the explain,"Only about 10% of the population is left-handed." I find this strangely accurate, because in our grade, there are four other lefties than myself. Further along, it explained the chances of being born to different-handed parents, "If your parents are both right-handed, there's a 10% chance you will be." I am in that minority as well, because both my mom and dad are righties. Later, they talked about how if there was more fight-to-the death survival of the fittest in human history, there would be 50% lefties and 50% righties. They explain, "Often, lefties are better at doing combat one-to-one sports, because the rightie would not know where their next move would be. But, we live in a cooperative society, not a fighting one, so there are less lefties." I thought this is really interesting, but it also makes sense. If somebody were to play baseball, and there was a leftie hitter, the righties would not be able to predict their next move, while if there was a right-handed hitter then they would be able to know their next move. It is not surprising though this that over 50% of the top baseball players were left-handed. Lastly, I wanted to mention a few left-handed people who succeeded and became famous: 1. Leonardo da Vinci 2. Michelangelo 3. Benjamin Franklin, 4. Joan of Arc, 5. Ramses II, 6. Alexander the Great 7. Napoleon 8. Julius Caesar 9. Charlie Chaplin 10. Barack Obama. I think this video helped me learn just why I'm a lefty.

Owen said...

I didn't think that identical twins could have different handedness. If they are genetically identical, it seems like they would have the same handedness. This tells us that handedness can't be all genetic. There has to be environmental factors that effect handedness. I also found it interesting that lefties are at an advantage when it comes to some sports and combat. I had never thought about this except for the example in baseball. I had heard that handedness did have an effect on a person's performance in baseball. I wish that the video has discussed why, for instance, so many presidents have been left-handed. Seems like there is something more to learn about whether there are any intellectual differences between right and left-handed people.

Jenna said...

I thought that this was a very interesting video because it talked about an cool subject. I know a few left handed people so I wanted to know why they have a different dominate hand. I thought that it was sad when they talked about there being more left handed people when fighting occurred. I wish we could still have a half and half environment of left handed and right handed people.

Jason G. said...

This was a really cool video. I think that this one of the most fascinating topics in the world. Also, this seems like a pretty obvious question that people don't really think about... until they have to. I don't think that we have figured it out yet. We probably won't figure it out for many decades. I did some research and I think that most celebrities are left handed. To consider that there are only 10% of people in the world that are left-handed, many celebrities are left-handed. Now, that's a TedEd video.

Natalie said...

Especially because I am left handed, I enjoyed this video a lot, because when I first saw this I knew I had to watch the video. It is interesting to me how only ~1/10 people are left-handed, and forced to be a righty. It is perfect how the human world is imperfect, as to say, when it comes to this. Lefties wouldn't be special after some time if the human race was completely competitive, but thankfully (to lefties), we're actually equally competitive and cooperative. The lefties of the world are supposed to become so special that they aren't special, but they still are special. There are pros and cons to this: Lefty pros: Lefties are special, and if you have them on a sports/competing team, the person fighting against the lefty won't have very much practice on the lefty, therefore giving the lefty the upper hand (see what I did there). But, when it comes to safety and tools, lefties aren't prepared, and it's hard to find gloves or machines fitting lefties. This gives them higher accident rates, of course very dangerous.

Julianna said...

This was an interesting video, but it didn't quite answer the question of WHY people are left handed. I know there are not many left handed people who were sometimes forced to be right handed, but that doesn't answer the question. Left handed people have to be cautious with items, made for the right hand. It could be very dangerous if not used properly or correctly. Only 1/10 of people are left-handed, and that is interesting. I would think there would be not many lefties, but not as little as 1/10! Anyway, I think it is special and cool to be left-handed (though being right-handed is good too), but could cause some problems.

Siji said...

I wonder if left-handedness is actually because of a very common genetic mutation, like if a certain collection of DNA was easily changed and mutated to create left-handedness.

Talia said...

This is a really weird but interesting video. I had never thought of this or asked about it, for it isn't really that useful to know, but it is interesting. Some of the video was kind of confusing, like that part with the fighting and base ball and genetics, but the rest was pretty clear. I still don't really get why some people are left-handed, but now I am curious and want to learn more. I wonder why there are so many lefties, why there are so many righties in the world, why it isn't the other way around. Also, I thought it was really weird how people used to think that it was "wrong" to be left-handed and taught them to be right-handed. It just makes you see how messed up we used to be, thinking that it was "wrong" to be black or left-handed. If you think about it, it sounds seriously stupid. I think what Siji said is interesting. I am also wondering the same question. I searched it up and couldn't really find much. On many websites it just said that it is an open-ended question that nobody KNOWS for sure. I think that it probably has something to do with DNA because there aren't that many other real-sounding explanations that I have heard. I would like to see more videos with TedEd and maybe some articles on this particular topic.

Talia said...

I agree with Julianna, they don't tell us WHY, more of how, and facts that don't have to do with the WHY. I looked up WHY and I actually found lots of real published books about that. They all say different things. Some say it is genetic, some say it is because of you, some say it depends. I also wonder why there are different things for left-handed people. What is the difference between a left-handed golf club and a right-handed golf club. This doesn't really have to do with WHY people are left-handed or right handed, but they are some interesting things that I would like to know.

I looked it up, and here is a link with SOME of the answers:

http://golftips.golfsmith.com/difference-between-right-left-hand-golf-clubs-20677.html

Sophia said...

I think this is a really interesting article. I don't think it was right back then, that if you your a lefty you had to learn to eat and right with your right hand. It is not good that people think that being left and is terrible and not right. I think it is cool and good that it can depend on tour birth if you are positioned in the womb. Also it can be genetic. I think it is cool that indentical twins can have the same jean, but be different handed then each other. That is so cool. Now I know my my brother is left handed.

Conor B. said...

I thought that this article was absolutely amazing, as I have attained a personal fascination with the process of evolution and genetic manipulation over lengthy periods of time. But there is one major qualm I have with this theory, and I present it to you. If, in our world today, we are over 90 percent cooperative, then why do any left-handed humans still remain? I see no advantage that left-handed people have over those who are right-handed, and they are only penalized for not being able to utilize common tools as efficiently and effectively. If left-handedness is so detrimental, I do not see a reason that the process of natural selection would have allowed an inferior species to survive. It contradicts Darwin's evolutionary theory, which states that survival of the fittest is the basic course of evolution. I have one hypothesis, though, why left-handed people may still be left in such a high (scientifically) concentration. Let me begin with a few facts, assuming that evolution is a kind of omniscient being that controls how we develop. Evolution is much more intelligent than we can comprehend, accounting for all potential happenings. Secondly, evolution is extremely paranoid, not wishing to relinquish any benefits which may allow a species to prevail in times of danger. Keep these facts in mind while reading the theory. I believe that if the population of left-handed people was eradicated, than right-handed people would have less of an advantage in combat. Think about it. If there were no lefties, righties would never need to prepare to face them, reducing their overall effectiveness. Therefore, theoretically, we humans would begin to decline in power. Although we are in complete and utter control of Earth at this moment, the evolutionary process demands perfection in every way possible. Thank you for listening! Please respond with a rebuttal or additional information!

Ayden said...

This was interesting to think about handedness. The video went into how in a right hand based world, lefties were at a disadvantage. And so their population started to decrease. But what I want to know is why the world was right hand based in the first place. Was it because righties just happened to be more common, and so started to take over society? The video also mentioned that lefties were at an advantage when it came to sports and fighting. It makes a lot of sense, and now I know why the lefties keep beating me in fencing.

Celene A. said...

This is a very interesting topic. I was surprised to learn that left-handed pitchers in baseball are more able to throw the ball, where as a right-handed pitcher would more easily be thrown off. I also think that the genetic aspect of this topic is extremely interesting. This video surely did get into A LOT of detail.

Jaime said...

This video was very informative. I didn't know that there is a less chance of being left handed vs. being right handed. Even if both of your parents are left handed, you only have a 25% chance of being born left handed. But, the world has made materials that are a lot harder for left handed people to use, like scissors, notebooks, and many other useful tools. If we did not cooperate, there would be more right handed people, because they can use all of these supplies easily and have a greater chance of being born. But, if the world was more competitive, the chances of being left handed and right handed would be equal. For an example when left handed person is playing baseball, a lot of the people are right handed, so if someone is pitching a left handed person, the batter, or left handed person, would have a better chance of hitting a home run, or the other way around.

Rhea M. said...

I have always wondered why some people are left handed and it makes sense becuase no one is my family tree is left handed. So even if 25 percent there is no one. I also feel that it is important that the world makes supplies easier and easier accessible to lefties. Such as scissors golf clubs and others. I also think that it is unreasonable to say that there will be a rare population of lefties soon and that they are pressured by right handed people. plus we shouldn't be that competitive. Left handed people are special and have some advantages such as baseball but i though that this was very informative

Justin Y said...

I think this is so cool because my dad is left handed and my mom is right handed and so it showed that there was only a 17% chance that their children would be left handed, but I am ambidextrous. Also I think that is explained why my dad golfs right handed even though he is left handed but he batts left handed. I think that the rarity of left handed is showed brilliantly in the way that in a competitive society there would be more left handed people but in a cooperative society, which there is more today there are more right handed people.

Justin Y said...

I think this is so cool because my dad is left handed and my mom is right handed and so it showed that there was only a 17% chance that their children would be left handed, but I am ambidextrous. Also I think that is explained why my dad golfs right handed even though he is left handed but he batts left handed. I think that the rarity of left handed is showed brilliantly in the way that in a competitive society there would be more left handed people but in a cooperative society, which there is more today there are more right handed people.

Sydney said...

This is really interesting! I knew that lefties are rarer than righties, but I didn't know that it was because of cooperation versus conflict, and how baseball players are 50% left handed and 50% right handed, while only 4% of golfers are left handed. How most things are made for righties is interesting, and I think that more things should be made to suit lefties so they don't get injured by things like irons that are hard to handle with their dominant left hand.

Josephine said...

I am not left handed but a bunch of my friends are. I do not understand why there is a type of discrimination towards left hands. I think that people should be able to use their dominant hand and not be forced to use their right/correct hand. I really think that the way that handedness could be passed down in genes is so interesting. Both of my parents or right handed so then I should think that I am right handed. I have been practicing my left handed writing. I also think that it is so interesting how left handed people have a better chance of winning in sports like baseball and boxing. It is also so cool how identical twins can have a difference in handedness because I always thought that identical twins are pretty much identical. I thought that this video was very interesting and I would like to learn more about left handed people.

Lily S. said...

I really liked this video. I thought it was strange how the position in the womb affects your handedness. I never knew that iron were made for right-handed people. I knew that scissors were. It was interesting to learn that in other places in the world left-handed people are forced to eat and wright with their right hand. I have always wondered why the word right had those two different meanings. Now I know. I am left handed, but I can still cut with my left hand. The scissors for left-handed people are a lot harder for me to use. It was also interesting to learn that lefties are only 10% of the world! It was also interesting to learn that people who have two parents who are right-handed have a 10% chance of being left-handed. I was one of those 10%! I thought the fact that there are different ways that handedness balances out with the cooperative and competitive factors. I liked thinking about left-handed baseball players have an advantage over right-handed players. The reason for this is because left-handed players practice with right-handed ones, and right-handed players practice with right-handed ones most of the time. The reason that 90% of the world are still righties is because of everyday tools being made for right-handed people. Some examples are the sewing machine, notebooks, and the can opener. This means that left-handed people are more likely to have accidents. I really liked learning about why some people are left handed and I hope they make more videos like this.

Ben V. said...

I thought that this article was very interesting. It is funny how left-handedness was associated with evil, and I know that our English word sinister comes from the Latin word for left, and our English word ambidextrous means both right. It was also pretty cool how that roughly the same percentages existed from 500,000 years ago to now when it came to the likeliness of left-handedness. I found it also very interesting that mathematicians have shown that one reason left-handedness was around was because of competitive and cooperative pressure on human evolution. Another interesting detail was that it was shown that being a lefty was better than being a righty when it came to sports activities. An example of this, was in a sport I love––baseball. 50% of baseball players are left-handed. This shows that they are very successful, because again 10% of people are left-handed. It said that lefties will be better prepared against righties, but I don't think this is necessarily true because since a team has a balance of lefties and righties, righties can face lefties and lefties can face righties. Although, I do see how an imbalance in lefty vs. righty population, can result in an advantage for lefties in sports and fighting. Another thing that was funny was that in golf there are almost know top lefties because it is not like a one vs. one in the sense of boxes, baseball, etc. I have always wanted to be completely lefty because it gives an advantage in baseball, but in the cooperative sense, it would be very hard for most tools are designed for righties.

Olivia said...

I enjoyed this video, because it answered a curiosity I have always had. I have always wondered if it is possible to train both hands, or if some people chose to be lefties. I had no idea that 10 percent of our population is left handed. I had no idea that left-handed people were more accident prone. However, this video did not answer all my questions about lefties. During further research. I have found that being left handed has a few advantages such as a "secret weapon" or "surprise" in sports and other athletics. However, I also found many disadvantages such as lefties having a higher risk of psychosis (A mental disease where one looses connection with the rest of the world), a higher rate of dyslexia, and often more sensitive to fear, tend to have more of a temper than right handed people. (http://www.everydayhealth.com/healthy-living-pictures/little-known-facts-about-lefthanders.aspx#14)

Maxwell said...

It is odd that people were forced to eat with their right hand and that they thought that the right hand was the "proper hand". Though it is common to say that right is the right way and left is the wrong way. Today 1/10 of the population is left handed making right handed people so common and left handed people strange/rare. From archaeology we have learned that it has been that way for about 500,000 years. You also learn if you are left handed or right handed when you are in your mothers belly, it decides on what hand you mainly use. What I found crazy is that twins have as much of a chance to be different handed than brothers and sisters, or just siblings in general. It is odd that if your father is left handed and your mother is right handed you have only a 17% chance to become left handed. Does the mother have a overrule on what hand you are. Though if both parents are right handed you have only a 10% chance to be left handed. Almost all of todays activites are meant for right handed people making left handed people having a harder time and have a higher accident rate when doing daily activities

Matteo said...

It is really strange how people have thought so greatly of the right hand and how lesser they have thought of the left hand. It is also weird that kids who were born left handed were forced to learn how to be right handed because right is "correct". I also find it amazing that left handed and right handed are dependent of your genes. And if your parents are a certain hand then that effects what you are. And it was cool to learn that left handed people are more associated with coopetitve things and right handed people are better at cooperative things. Overall thies was an interesting topic.

lennox said...

This is an interesting topic. I am ambidextrous. It is a little more challenging to write with my left hand. If I ever break my right hand then I can still write. I do not understand why a left handed baseball player is better than a right handed one.

Rohan said...

This is a very cool topic. I understand how left handed people would be better at sports (take the opponents by surprise), but I don't get how it would be an advantage in fighting or hunting. I also don't understand why we still have left-handed people. In the video it said that the population of left-handed people decreased because we are now in a cooperative word but why do they even have a tiny bit of left-handed people, why not just get rid of it? This was overall a cool and interesting topic.

Allie said...

I was really intrigued by this video. It was so cool about why people are left handed was based on your competitiveness. Also, lefties are better at sports, as Paisley said. Makes sense. I agree with Grace too. And probably everyone else. Also, I was a little surprised that identical twins could have different dominant hands, like Owen said.