Collage of ethnic groups (License: CC-BY-SA 3.0, Author: Collective)wikimedia commons
The context of ethnic variation here cuts across the scope of nationalities and transcends to the generality of human race categories which many countries fall either in one group or the other. The idea of ethnic variation is mainly the classification of people, not by their nationality but by their commonalities in social heritage. Like people who share origins or social heritage, culture and traditions that even transcends from generation to generation.
There are so many definitions of ethnic group or ethnicity which is anchored on a group of people that have common cultural origins, language, physical appearance, religion , dialect , society, dressing pattern, history and so on.
No one is very happy with the word "race", it has been too much a part of man's inhumanity or unkindness to man. But patterns of ethnic variation do of course exist fairly consistent differences in the physical characteristics of different people. We are all aware of how people vary in stature, skin colour, hair type, and facial features. But ethnologist also noticed things like blood type, the ability to taste certain substances, even the type of wax that forms in the ear, are part of the variety of human inheritance.
The world's population as a whole is under the three great or general ethnic groups which are caucasoid, mongoloid, and negroid. The differences within each group are as large as those between them. For instance, the old preoccupation skin colour negroids, range from near black to sallow (sickly pale colour), while mongoloids from yellowish to flat white to deep bronze, and caucasoids from fair pinkish in northern Europe, to the dark brown people of southern India.
The negroid share the same skeletal form and/or structural traits and they can be found mostly in Sub-Saharan Africa and secluded parts of South and Southeast Asia. Mongoloid are people who share the same phenotypic characteristics. Like the Chinese, Japanese, Korean, indochinese, North Mongol, Tibetan, Native American, Polynesian, Micronesian, Eskimo ,Malay and Burmes. The Caucasian race or Caucasoid includes some or all of the ancient and modern populations of Europe, Asia Minor, the Horn of Africa, North Africa, Caucasus,Central Asia, South Asia and Western Asia.
Another extreme variable is height. It is less totally inherited, and more immediately determined by environment, than other ethnic criteria. But not only does it range widely among individuals of a given people, but also between peoples of the same ethnic group. Height relates to ethnic factors, but little to overall ethnic group. Below left, average heights, for a sample selection of people, reveal a jumbled sequence of negroids, caucasoids and mongoloids . For example the negroid people are both shortest and tallest. Also, even within a people, other genetic and environmental variations prevent too much consistency. For instance, the height range shows the tallest pygmy as tall as the shortest Sudan Negro.
Body and Climate
As animals of different species differ in coat colour, size, limb length, and location of fat deposits, according to climatic conditions where they live. So is human variation related to climate. The environment did not make people acquire inheritable characteristics, but it did decide which characteristics flourished. Those people who flourished bred among themselves and passed on these features which are not of course lost if the inheritor moves to a new environment.
Skin colour is a well known example. The extra melanin in dark skins gives added protection against the sun. Pale skin allows better vitamin D formation, where the sun is no problem. Yellow skin contains a dense keratin layer that reflects light well in deserts or snow. Dark eye colour also protects against sunlight; and so do the thick, folded eyelids of mongoloids. Negroid hair protects against heat on the scalp, but allows sweat loss from the neck . Straight hair, grown long, protects against the cold. Noses typically vary with air humidity. In dry conditions they are longer and narrower, so inhaled air is moistened. But the flat mongoloid face developed as protection against the cold, and here the nose is not prominent and exposed. The Eskimo have taken this further, by developing facial fat.
Other Variables
Other features not entirely inherited, also vary with climate. Average weight is greater the colder it is. The Eskimo averages 170Ib, the Irishman 157Ib, the Spaniard 132Ib, the Algerian Berber 125Ib. Body shape also varies. Two bodies that weigh the same can have very different surface areas. Body area is larger,for weight, the hotter it is, for a large area gives more skin from which to sweat and to radiate heat. Metabolic rate varies in the same way. A typical European has a "thermal equilibrium" of 77°F, i.e with that temperature around him naked, standing still, he shows no tendency to get hotter or colder. The Eskimo's metabolic rate is 15 to 30% higher than the European's giving him a lower thermal equilibrium, while an Indian's, Brazilian's or Australian's rate is 10% lower than the European's.
Conclusion
Every human is categorize either in negroid, mongoloid or Caucasoid ethnic groups. Though someone could be an immigrant and as well participate in other ethnic culture. People can intermarry with other ethnic groups and thus learn their culture and traditions and become part of them. But it doesn't deny them of their true origin.
Thank you for reading!
References
[1] Ethnic Origin
[2] Human Variability
[3] Ethnic Group
[4] Negroid
[5] Mongoloid
[6] Causacian Race
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