See here for a slightly more modern viewpoint.
Studies conducted in the past have often not taken proper account of in-group variation both of genetic and environmental origins nor of the immense and rapid effect of environment and nutrition on metrics such as stature. In the presence of cultural (‘sexual’) selection, there is no reason to believe that facial characteristics are constant either. As a result, traces of race admixtures have often been claimed in what should properly be called a single race. These should be kept in mind while noting that, from anthropometric studies, one found traces of seven races of humans who intermixed to create the Indian race. For a slightly more detailed description, see the section on race in an analysis of the 1931 Census.
As a rough guide for understanding the description below, the height measures used are roughly: pygmy (less than 1480 mm), short (1480–1581 mm), medium (1582–1676 mm), tall (1677–1720 mm), and very tall (more than 1720 mm). The cephalic index is calculated by dividing the distance between the nasion and the occiput by the width. This divides people into dolichocephalic (less than 0.75), meso- or mesaticephalic (0.75–0.80) and brachycephalic (more than 0.80). Similarly the height of the nose divided by its width gives the nasal index which divides people into leptorrhine (0.55–0.77), mesorrhine (0.78–0.85), and platyrrhine (0.85–1.00).
(E) The tribal people of Andaman, Semang of Malaya peninsula, Angami Nagas of Assam, Kadar and Pulayans of Perambkulm and Annamallai hills may show existence of a Negrito race in the distant past in this region. These people are small bodied, dolichocephalic, platyrrhine, shining black, have wavy hair and thick upturned lips. Some genetic research indicates that the Andamanese may be more closely related to some African people than to the rest of the Eurasian ones. As the language currently spoken by these people belong to the Australesian group of languages, whether these are just a variation of the proto-Australoids discussed next, or whether, in fact, they are a separate race, is debatable. The Bagdis of Rajamahal hills in Bengal, some fisherfolk of Sundarvana and other parts of southern Bengal, and some tribes of Maimansingh and Jessore may show the influence of these people in Bengal.
(D) The Kol, Bhil, Karoa, Kharoar, Munda, Bhumija, Malpahari, Chenchu, Kurur, Kherur etc. show traces of the proto-Australoid race of people. These people are short, black, dolichocephalic, platyrrhine and have bronze coloured hair.
(A) A certain dolichocephalic people of middle build with short foreheads, short face, high cheekbones, long raised nose, thick lips, big mouth, black eyes, and light to dark brown skin seem to have lived all over from North Africa to North West India in the Paleolithic age, and moved all over India in Neolithic times. They probably form the base of many of the people in both North and South India.
A robust, big brained, big eyebrowed, big earboned dolichocephalic people seem to have contributed to the North Western India. Their influence may not have reached beyond Punjab.
A slightly short, not so robust, dolichocphalic race with sharp raised nose and bowlike bent forehead and similar to the Mediterranean races seem to have contributed to the people of India. These people may have been the main contributors to the Sarasvati-Sindhu (often called Indus valley or Mohenjodaro) civilization. Their contribution to the people of Bengal is unknown.
(B) A brachycephalic Alpo-Dinarian race spread from the North West and provides a pronounced brachycephalic character to a lot of races in India, including many peoples of Bengal. These people may have spoken an Indo-European language.
(C) A proto-Nordic (dolicho-)mesocephalic big-faced robust people with narrow raised nose, dark brown to black hair, and brown to red skin may have been the main Indo-European speaking race in India. They may not have contributed much to Bengali population, however.
(F,G) In addition, of course, small amount of trans-himalayan migration is always present and gives rise to other elements in the immediately adjoining regions.
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