Single Eyelids, or "asian eyes".
A lot of people talk about "Asians" , "CaucAsians" or other silly stars-upon-thars categories and assume that everyone knows what they are talking about, but what exact are they talking about?
What does it mean to be "Asian" and how is it different from any other word coined to divide people based on some phenotype differences?
It depends who you ask.
In England, some say that "Asian" should mean descendants of the area once ruled as British Raj (Now the sovereign territories of Pakistan, India, Nepal*, Bangladesh, Bhutan, and maybe Burma?)
*The Kingdom of Nepal was not ever under British sovereignty, although I assume that in England the ethnic term "Asian" would still apply to one who would identify as Nepalese.
Others in Russia, a country that is split in half by the Ural mountains, might refer to Asians as non-European Russians.
While some may assume Asian to include anyone from just the easternmost chunk of this great landmass (China-Taiwan, Japan, Korea, and Vietnam).
Still some may chose to include the Indonesian islands, Indochina, Siam and Malaysia.
Ironically very few will venture to include Iran or Iraq (don't know why??)
Borat might be referring to Kazakhstan and the rest of Central Asia.
Possibly some from the Balkans or Greece might just be referring to Turkey,
and a few brave souls may actually be referring to the whole darn landmass.
For the purpose of this note, East Asia will refer to the modern territories of China-Taiwan (but not Tibet and Xinjiang), Korea (North and South), Japan and Vietnam.
First of all, the concept of "from" also differs from place to place, and where to draw the line historically?
For some, "from" refers only to where one maintains permanent residence (that's me!). For others, "from" must mean where one spent early childhood. Others would like to stick to claims to citizenship and birth. Still others that might feel unsatisfied in immigrant communities may want to hear about birthplaces of parents or grandparents.
Then there's the ones that want to know information about everyone in one's genetic past as far back as one can possibly go, usually along the route of the surname (for most this is the patrilineal line) since the surname is the only thing left as a historical record to follow. These answers are usually based on 90% myth or legend and 10% actual recorded facts. For these, the line may be drawn as far back as one can go, but must not go back as far as the period when humans migrated out of Africa (not sure why this is not an acceptable answer?)
The other complicated concept of "from" is the idea of where to draw the line geographically?
Some may want to know "from" details on a geographic scale the size of Singapore which is not even visible on most world maps, whereas others are content with "from" answers as large as the diverse geographical territory of China.
When you combine those that want "from" answers going back as far as possible with the xenophobes demanding "from" information with geographic terms relating to the current nation-state borders, you will really run into some tricky problems.
The first problem is that the modern political concept of nationalism (and nation-states) has only been around for about 300 years. Anything before that was multi-lingual empires that would shift and change their territories dramatically depending on how well their kings rolled the dice.
The second problem is sex.
These "from" answers would be pretty straightforward if humans reproduced like yeast cells. unfortunately sexual combination means that the number of ones descendants explodes geometrically to the power 2 with ever generation. That means after 1 generation you have 2 parents, 2 generations 4 grand-parents, 3 generations 8 great-grandparents, and so forth and so forth, all with their own unique residential and migratory history. Assuming no inbreeding, by the time you go back 28 generations you find that your descendants at that time are numbered in the 200 million range, which was approximately the world population at that time. Is there anyone out there that has the audacity to claim that all of their 200 million ancestors came from one small geographic chunk of the world? Or would it be more appropriate to admit that he/she is the product of some seriously intense inbreeding?
So now that you are completely confused on this concept of "from", we'll dive even further into genetic phenotypes.
Genetic variation exists in populations around the world, and there's hardly any evidence linking place of birth, and genetic makeup. See my post with Bill Nye and Race to see how he is dumbfounded on his preconceived notions of geographic origin.
You may be wondering . . . yea but what about dark skinned people in Africa and funny-eyed people in East Asia?
Skin tone is partly inherited, and partly determined by environmental factors throughout an individuals life. In all cases it is a function of how much melanin one has in their skin. The genes that determine what tone human skin will be are the same as those that do the exact same thing for cows and other mammals.
Melanin content in the extremes can have some negative health side effects, for example too much melanin blocks the UV rays necessary for vitamin D synthesis, whereas too little melanin leaves the sensitive dermis exposed to harmful radiation and possibly folate deficiencies.
The complicated part about skin tone as a way to categorize communities of people is that there are a nearly infinitely many ways of dividing color tones ranging from 0 melanin (albino) to the highest content known to exist in humans. In other words, any attempts to categorize leave you with a whole lot of ambiguous browns = (
Browns are found in various locations throughout the world, and it is only in the social constructed perceptions that light-browns may be distinguished from dark-browns. Most likely these socially constructed divisions may have originated from the caste system in India, where lightness of skin was linked to a progression up the caste system to the Brahman elite. These skin-tone ideas may have been picked up by the British and then used as a way to justify land seizure and slavery in Africa.
Eye features is an incredibly complicated process that is a combination of genetic as well as environmental factors. everything from skull shape, diet, exercise, allergies , and particularly emotions may drastically change the shapes and features of one set of human eyes. Not only that, but now plastic surgery may add additionally drastic permanent effects to the outward superficial appearance of eyes.
What is it about the eyes of a lot of people who live in East Asia that makes them appear unique to that part of the world?
The unique look of eyes seen in East Asia is a combination of two different features known as epicanthal folds and single eyelids.
Everyone is apparently born with epicanthal folds, but some later grow out of it as the features of the bridge of the nose start to pull the excess skin away from the eye. Those with less pronounced nose bridges will have a distinct epicanthal fold. Epicanthal folds come in a spectrum of variety, just like skin tones, and are one contributing factor to the outward appearance of eyes.
Single eyelids is an extra layer of fat in the upper eyelid that distinguishes it from the double eyelid appearance in which there is a noticeable eyelid fold between the tip of the eyelid and the eyebrow. Just like the epicanthal folds, the degree of double-eyelidedness is extremely diverse, and many different varieties exist as to where the eyelid crease is, as well as how pronounced the crease is. The appearance of the crease is also dependent upon environmental factors such as emotion, light intensity, or allergies.
Some hypothesize that the correlation between East Asia and the single eyelid is because of early adaptations to harsh winter conditions, and later aesthetic preferences and sexual selection.
Others in Russia, a country that is split in half by the Ural mountains, might refer to Asians as non-European Russians.
While some may assume Asian to include anyone from just the easternmost chunk of this great landmass (China-Taiwan, Japan, Korea, and Vietnam).
Still some may chose to include the Indonesian islands, Indochina, Siam and Malaysia.
Ironically very few will venture to include Iran or Iraq (don't know why??)
Borat might be referring to Kazakhstan and the rest of Central Asia.
Possibly some from the Balkans or Greece might just be referring to Turkey,
and a few brave souls may actually be referring to the whole darn landmass.
For the purpose of this note, East Asia will refer to the modern territories of China-Taiwan (but not Tibet and Xinjiang), Korea (North and South), Japan and Vietnam.
First of all, the concept of "from" also differs from place to place, and where to draw the line historically?
For some, "from" refers only to where one maintains permanent residence (that's me!). For others, "from" must mean where one spent early childhood. Others would like to stick to claims to citizenship and birth. Still others that might feel unsatisfied in immigrant communities may want to hear about birthplaces of parents or grandparents.
Then there's the ones that want to know information about everyone in one's genetic past as far back as one can possibly go, usually along the route of the surname (for most this is the patrilineal line) since the surname is the only thing left as a historical record to follow. These answers are usually based on 90% myth or legend and 10% actual recorded facts. For these, the line may be drawn as far back as one can go, but must not go back as far as the period when humans migrated out of Africa (not sure why this is not an acceptable answer?)
The other complicated concept of "from" is the idea of where to draw the line geographically?
Some may want to know "from" details on a geographic scale the size of Singapore which is not even visible on most world maps, whereas others are content with "from" answers as large as the diverse geographical territory of China.
When you combine those that want "from" answers going back as far as possible with the xenophobes demanding "from" information with geographic terms relating to the current nation-state borders, you will really run into some tricky problems.
The first problem is that the modern political concept of nationalism (and nation-states) has only been around for about 300 years. Anything before that was multi-lingual empires that would shift and change their territories dramatically depending on how well their kings rolled the dice.
The second problem is sex.
These "from" answers would be pretty straightforward if humans reproduced like yeast cells. unfortunately sexual combination means that the number of ones descendants explodes geometrically to the power 2 with ever generation. That means after 1 generation you have 2 parents, 2 generations 4 grand-parents, 3 generations 8 great-grandparents, and so forth and so forth, all with their own unique residential and migratory history. Assuming no inbreeding, by the time you go back 28 generations you find that your descendants at that time are numbered in the 200 million range, which was approximately the world population at that time. Is there anyone out there that has the audacity to claim that all of their 200 million ancestors came from one small geographic chunk of the world? Or would it be more appropriate to admit that he/she is the product of some seriously intense inbreeding?
So now that you are completely confused on this concept of "from", we'll dive even further into genetic phenotypes.
Genetic variation exists in populations around the world, and there's hardly any evidence linking place of birth, and genetic makeup. See my post with Bill Nye and Race to see how he is dumbfounded on his preconceived notions of geographic origin.
You may be wondering . . . yea but what about dark skinned people in Africa and funny-eyed people in East Asia?
Skin tone is partly inherited, and partly determined by environmental factors throughout an individuals life. In all cases it is a function of how much melanin one has in their skin. The genes that determine what tone human skin will be are the same as those that do the exact same thing for cows and other mammals.
Melanin content in the extremes can have some negative health side effects, for example too much melanin blocks the UV rays necessary for vitamin D synthesis, whereas too little melanin leaves the sensitive dermis exposed to harmful radiation and possibly folate deficiencies.
The complicated part about skin tone as a way to categorize communities of people is that there are a nearly infinitely many ways of dividing color tones ranging from 0 melanin (albino) to the highest content known to exist in humans. In other words, any attempts to categorize leave you with a whole lot of ambiguous browns = (
Browns are found in various locations throughout the world, and it is only in the social constructed perceptions that light-browns may be distinguished from dark-browns. Most likely these socially constructed divisions may have originated from the caste system in India, where lightness of skin was linked to a progression up the caste system to the Brahman elite. These skin-tone ideas may have been picked up by the British and then used as a way to justify land seizure and slavery in Africa.
Eye features is an incredibly complicated process that is a combination of genetic as well as environmental factors. everything from skull shape, diet, exercise, allergies , and particularly emotions may drastically change the shapes and features of one set of human eyes. Not only that, but now plastic surgery may add additionally drastic permanent effects to the outward superficial appearance of eyes.
What is it about the eyes of a lot of people who live in East Asia that makes them appear unique to that part of the world?
The unique look of eyes seen in East Asia is a combination of two different features known as epicanthal folds and single eyelids.
Everyone is apparently born with epicanthal folds, but some later grow out of it as the features of the bridge of the nose start to pull the excess skin away from the eye. Those with less pronounced nose bridges will have a distinct epicanthal fold. Epicanthal folds come in a spectrum of variety, just like skin tones, and are one contributing factor to the outward appearance of eyes.
Single eyelids is an extra layer of fat in the upper eyelid that distinguishes it from the double eyelid appearance in which there is a noticeable eyelid fold between the tip of the eyelid and the eyebrow. Just like the epicanthal folds, the degree of double-eyelidedness is extremely diverse, and many different varieties exist as to where the eyelid crease is, as well as how pronounced the crease is. The appearance of the crease is also dependent upon environmental factors such as emotion, light intensity, or allergies.
Some hypothesize that the correlation between East Asia and the single eyelid is because of early adaptations to harsh winter conditions, and later aesthetic preferences and sexual selection.
The truth is that even within East Asia, it is difficult to classify a representative trait, since 80% of Korean residents have single eyelids and only 50% of Chinese residents have single eyelids, the trait is far from predictive of East Asian residency. In addition, the same gene that determines whether East Asians will develop single eyelids is also found in Bushmen tribes in Africa, proving that this trait is by no means unique to East Asia, but instead merely highly correlated. Regardless, these single-eyelids and epicanthal folds have so many variations that they hardly make adequate features for racial categories.
Humans have all sorts of variety, not just on skin tones or eye features, but also in this such as attached earlobes or the ability to smell cyanide or color blindness. If we found a population of people in Bhopal that could smell low concentrations of MIC should we make a new race for people who can detect MIC? What is so special about eyes and skin tone?
The answer lies in the fact that humans are visual creatures with an insane amount of brain real estate devoted to facial recognition. Humans feel the urge to categorize people based on outward appearance as a result of this affinity to visual information.
Humans have all sorts of variety, not just on skin tones or eye features, but also in this such as attached earlobes or the ability to smell cyanide or color blindness. If we found a population of people in Bhopal that could smell low concentrations of MIC should we make a new race for people who can detect MIC? What is so special about eyes and skin tone?
The answer lies in the fact that humans are visual creatures with an insane amount of brain real estate devoted to facial recognition. Humans feel the urge to categorize people based on outward appearance as a result of this affinity to visual information.
Can we as civilized humans also resist this urge to categorize people based on outward appearance?
References
Blog description of how humans perceive faces - specifically eyes, and how those perceptions relate to "beauty", and recognition of Asian, or any other ethnic distinction
Study on variations in eye features within and between ethnic groups
Study concluding that eye variations between Asians and Caucasians is the same as that between Native Americans and Caucasians
3 comments:
Nepal was not ruled by Britain ever.
to anonymous -- true
That was supposedly the reason why the British recruited the Nepalese as an elite task force unit in the British Army known as the gurkha unit. Today in Singapore gurkha units may be found at high profile events like WTO or IMF conventions.
Additional information on "asian eyes" from
http://asianeyes.wordpress.com/beauty/
Why do Asian eyes appear so differently than Caucansians and African Americans?
The Asian periocular anatomy is very different from that of a Caucasian or African American on many levels. Firstly, the shape of the orbital bones make a tremendous impact on the 3D shape and angle that the eyelids slant. In an Asian, the lateral orbital rim, or the rim of bone that can be felt at the outer corner of the eye, sits on average 3mm more anterior than Caucasians, and 5mm more anterior than African Americans (Migliori and Gladstone 1984, Tsai et al 2005). This difference in the skull shape primarily explains the highly angular corners of Asian eyelids compared to the more rounded outer corner in Caucasians and African Americans
Secondly, the fibrous band of tissue called the tarsus, that gives the eyelids their smooth contour, is significantly narrower in the Asian patient (6-8mm) than in Caucasians and African Americans (10-12mm). The upper edge of the tarsus is where the fine filamentous attachments fix the skin to the eyelid creating the lid crease. The normal height of the eyelid crease for Asians or non-Asians corresponds to the height of the upper lid tarsus.
Another difference is the additional layer of fatty tissue in Asian eyelid that is not found in either Caucasians or African Americans. This extra layer of fat helps to separate the eyelid skin from the muscle and tarsus, which is typically firmly attached in Non-Asians. By increasing the thickness of Asian eyelids, this layer may prevent a lid crease from forming at the upper border of the fibrous tarsal edge.
Summary of thoughts on the subject as of 25 JAN 09
The concept of race in connection to physical appearance has a very limited, superficial significance that appears to be some qualitative way of describing combinations of skin tone and eye features similar to the way the word "genre" describes musical pieces, but has no real measurable connection to genetic ancestry. The nature of describing these skin and eye variations is highly subjective, and does not fit within a rigourous statistical definition of a "group", but is more of a tag or set of vocabulary used to describe a particular feature.
For example:
She has "Asian eyes" does not imply that the appearence of her eye would statistically place her in some supposed "Asian" group of people, but rather the simple observation that the appearance of her eye is similar to the appearance of a lot of eyes in Asia.
If we did place her in a group defined by this type of eye appearance, then we would at some point have to abandon the relevance to Asia, because we would be throwing in indigenous populations from all over the world (50% of Chinese, 80% of Koreans, Native American Indians, African tribes, etc..)
This concept of race based on physical features is in contrast to the concept of "ethnicity", "nationality", "religion" etc.. which are socio-political constructs that people use as a way to identify themselves. Often times race is also used interchangeably with these words.
When used in context of socio-political identification, "race" would have more significance, because self-identification would have an influence on values, behavior, environment and lifestyle, which would have an impact on other variables such as IQ, health, etc..
The US census beaurea defines race along the latter use of the word, merely as a grouping of ethnicities by continent, and explicitly states that its use is not intended for biological contexts.
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