Friday, December 21, 2012

History of wedding rings


Hi again. Well I've gone and done it again and stumped myself in a conversation. My friend and I were discussing wedding rings the other day. She's getting married soon and was wondering what my partner and I had done for our wedding rings. As the discussion progressed we started to wonder whether all cultures have wedding rings and if so, if they also customarily wear them on their left hand. It seems that there may be some cultural/generational differences if my parents serve as an example, neither of them has worn a wedding ring for as long as I can remember and it doesn't seem to bother them any. So what is the deal with wedding rings, where do they come from, why do we wear them rather than signify our romantic commitments in other ways? 

The google search

Wikipedia is always a nice place to start. 
According to wikipedia, the tradition of wearing a ring started in Egypt. This was coroborrated by a few other websites. Although I had a very hard time finding any more official or academic websites, not connected to some sort of online jewelry seller. 

Not too surprisingly, it appears that traditionally only women wore rings and it wasn't until much later that men began to wear them as well. *Funny, note that with my engagement ring, I insisted that my partner also wear one if I was going to, and it seems that others have also done this - new trend?*

In my original conversation, my friend and I came up with the theory that wedding/engagement rings must have something to do with the symbolism of a circle - eternal love - all that sort of thing

http://slowbuddy.com/photography/pictures-of-love/
http://slowbuddy.com/photography/pictures-of-love/





but no. Instead, which makes so much more sense, it's all about money$! 

http://express.howstuffworks.com/wq-money.htm
http://express.howstuffworks.com/wq-money.htm

Rings were most likely a way of sealing the promise of an exchange of monetary value between the two families. In a sense that tradition continues to this day, with people who appear to need the largest diamond ever excavated sitting on their finger, to prove to them that their partner is going to be willing to pay for every little need/desire they may have in their remaining years on this earth.Granted, I understand that some people just really like diamonds. ;)

Here are some other handy little facts that I found across multiple unsatisfactory websites and collected for your enjoyment: 

1) The ring may traditionally be worn on the left hand because Egyptians and Romans understood that a major artery connected this location to the heart. The Romans apparently called it the Vena amoris - vein of love. 

2) As my friend and I hypothesized, the ring is also worn both for it's symbolism of eternity and for the symbolism of capturing the spirit.

3) The hole of the ring can symbolize an entrance into the unknown.

4) In some other countries, such as (apparently) France, women sometimes wear three intertwined rings, symbolizing friendship, fidelity, and love.

5) Historically, rings were not always high value items. Some believe that initially plant materials were used, then metals such as iron or copper, and finally more "precious" metals such as gold, silver, or platinum.

And then there are the modern inventions.

http://thecheeky.com/anti-cheating-ring
http://thecheeky.com/anti-cheating-ring

For more interesting facts, check out this website, although it's associated with a jewelry seller, it's fun and interesting. Not sure where her information came from though, since she cites no resources.

And one more website for information about different ring practices around the world. Although, again, the author cites no resources. 

And the closest to an academic book about the topic that I could easily find.

Enjoy!

Sunday, March 18, 2012

What's the deal with handedness?



When re-learning how to snowboard recently, my friend and I encountered the same problem that I'd always had, how to figure out which foot was dominant. That's the foot that's supposedly going to lead you down the mountain most comfortably. During my last stint with snowboarding, I never figured out which foot was dominant. I had the experience of just constantly switching back and forth between which foot faced forward. As it turns out, my "footedness" is probably just not super strong in one direction or the other, but once I start pushing myself to do harder actions, I eventually do favor putting my right foot forward (goofy foot).



*As a random note to any folks out there with a similar issue: the classic test of "footedness" is for someone to push you and see which foot you place forward to catch yourself - this doesn't work consistently for me. However, there is a more appropriate test that helps you figure out which foot you might favor for sliding down a huge mountain of snow - wear some slippery shoes on a slippery surface, preferably with soft edges, in case of balance failure, run, and slide. You will most likely always put one foot forward if you don't force yourself to do it differently. ;)*



You're probably wondering at this point what all this has to do with handedness when all I've been talking about is feet! Well, our instructor for the day apparently thought himself a bit of a geneticist and told us all about how there's no gene for "footedness" and then something about handedness that in my tired, cold, and incredibly hungry state I translated as such: "There is no gene for left-handedness. Everyone starts out as left-handed and then if a gene gets turned on, you end up right-handed." I believe that sexual differentiation works somewhat like this, females being the default, but I had no idea that handedness might work the same way. So I looked it up and as it turns out, handedness is a complicated and I guess somewhat controversial topic.


The google search

Well, not too surprisingly, wikipedia was my first stop and it did list most if not all of the major theories that I could find through other sources such as online databases. However, the article was fairly muddled and seemed to mix the theories of left-handedness with descriptions of what it's like to be left-handed and the like. So, for the sake of simplicity, I'm going to list just some of the theories that I've found so far:


 
Socially learned theory: This one is fairly self explanatory. Some people think that you learn which hand to use by watching others when you're a kid. This doesn't really hold much water since many if not most left-handed kids have right-handed parents.




For fun brain lateralization info: click picture
Brain lateralization theory: This is less a theory about why kids are left-handed and more a theory about how they are left-handed. In this theory, essentially, true left-handed people have the opposite brain lateralization as right-handed people. Which means that while right-handed folks process things like language on the left side of their brain, "true" left-handed folks process language on the right side of their brain. This apparently does generally bear out using FMRI studies, however, there are left-handed folks that process language on the left side of their brain, like right-handed folks. Some use the socially learned theory, or other theories to try to justify those anomalies, but I couldn't find much consensus about it. One thing that does seem to be mostly certain is that if you process language on the right side of your brain, you are most likely left-handed. However, the relationship does not go the other way. If you are left-handed, you don't necessarily process things differently than your right-handed compatriot.


Prenatal hormone imbalances: again, I think this one is fairly self-evident. Some folks believe and there does seem to be a bit of evidence for this, that differential hormone exposure before birth, while in the womb can be a causal factor in the determination of handednes.




There's also the Vanishing twins theory that essentially states that everyone who is left-handed was actually part of a pair of twins and that their twin was never quite formed and thus only they popped out (not quite a technical term =P). This is because twins apparently come in Left/Right pairs at a very high rate.




The Right Shift theory: The closest thing to what my snowboarding instructor mentioned is this theory. This theory basically a single-gene theory, from what I can tell, and states that there's a gene for right-handedness, but no gene for left-handedness. The right-handed gene makes the left side of our brain dominant and thus we become right-handed. This will happen if a child is heterozygous right (CR) or homozygous right (RR). However, if this gene is not active (not sure if that's the technical way to state it) then there is no hemisphere dominance at birth and handedness is essentially decided at random. This one seems to actually pull together some of the ideas in the previously described theories. We have a genetic component that links to brain lateralization, that when it's shut off is basically dictated by epigenetic factors such as prenatal hormones and possibly social learning. But this does leave out the anomalies: folks who are left-hemisphere dominant, but also left-handed, so maybe there's still a place for other theories

One of the many reasons there are so many theories about handedness is because while it does occur at a fairly regular rate in the population, many people believe that it is not hereditary. Many if not most left-handed kids have right-handed parents. This leads many to believe that, like many if not most of our traits, handedness is determined by a combination of factors including both genetic and non-genetic. However, some folks have found recent evidence of a gene linked to handedness. This gene was found to have a link to handedness by linking to brain lateralization (and possibly other things like schizophrenia, but not to worry they say...).

At this point, I guess my snowboarding instructor was kinda right. Most researchers nowadays agree that handedness seems to act in accord with models of a single gene. And given the proportion of right vs left-handers in the population, that gene most likely codes for right-handedness. If the gene is active, then the person turns out right-handed. If the gene isn't active, then it's at chance whether the person is left or right-handed, but that single gene will be enough to skew the distribution of handedness toward the right. We'll how the evidence bears out in the future, but for now I'll just be content to have finally figured out my own foot status when throwing myself down a snowy mountain. =)

Monday, May 16, 2011

Cougar vs Panther?

VS

The other day I was talking to a friend about Mountain lions on the West coast of the U.S. and she asked what the difference between a mountain lion and a cougar was. I said that they were the same thing and that in fact I'd heard the mountain lion called by a number of different names: cougar, panther, mountain lion, puma, wildcat, etc. She was confused when I mentioned panther. She asked if it's the same as the African panther and I had no clue. I figured they could be the same, just different morphologies.

The google search

My first search for "what is a mountain lion" - I know, not super creative, but hey, it worked - brought up trusty old wikipedia as the second finding. Interestingly, the wikipedia entry was the one for cougar. It appears that, at least for wikipedia folks, mountain lions are most properly termed cougars. ;) A quick look at the wikipedia entry confirmed the confusion with names. Apparently, mountain lions actually hold the Guiness record for animal with the highest number of names - although I wasn't able to confirm it on the Guiness website...

From the wikipedia article I found the taxonomy of the mountain lion and it turns out that it's a member of the Puma genus. Another funny thing about them is that they are supposedly more closely related to the domestic cat than to the larger cats such as lions or tigers. This of course led me to search for what a panther is. Here's my very rough and quick summary:

The word Panther, typically refers to black panthers which are melanistic (black color variant) versions of jaguars (in Latin America) and leopards (in Asia/Africa).

This fella here

Both jaguars and leopards are members of the genus Panthera - hence the panther name - which is a genus that includes the big cat species, lions, tigers, leopards, and jaguars. Mountain lions are members of the Puma genus, as I mentioned above, and as such, are not the same as panthers.

Gratuitous cool mountain lion picture

There have been some supposed historical siting of melanistic versions of the mountain lion, which may have led to the use of the term panther. One of the things that distinguishes the members of the genus panthera from members of the genus puma (of which there are apparently only two species) is that the large cats (panthera) are able to roar, while mountain lions produce a high pitched shrieking sound instead and this is how the two genus are split up.

So that's your lesson in panthers and mountain lions for today. I hope you've enjoyed. =)


Here are some cool websites to check out if you'd like to learn more about the largest of the small cat species and the fourth largest cat in the world!

- National Geographic website
- San Diego Zoo website