Saturday, August 25, 2007

Absurdities of caste genetic studies

The population genetic studies on caste population that began truly with Bamshad et al. (2001) study has seen many additions in the last six years. In one of my previous posts I had discussed about total lack of knowledge on part of Geneticists about internal migrations of Indians and the unique political developments in central and eastern India.

Aryan Invasion Theory and Bamshad et al.
The mainstream anthropologists now mostly hold Aryan Migration Theory in place of Aryan Invasion Theory. However, this study conducted thousand miles away from the region of putative Aryan invasion concluded that Aryans indeed invaded and developed the caste system.

The study has following drawbacks:
a. Kshatriya problem
-> It cannot distinguish Y-Hg-R1a1 of so-called Aryans( a misnomer in my opinion) from that of later invaders.
-> East and Central Indian tribes did become Kshatriyas married other ruling families (See my post: Identities - II)
b. Dravidian genes
-> Even today Dravidian genetic composition is unclear. The biggest Indian Y-Haplogroup H is too old in India to be associated with any linguistic family.
c. R1a1 problem
-> The idea behind selecting a South Indian state being north India was too much mixed with the later invaders to retain the purity of original Aryan composition. However, this does not negate the fact that Haplogroup R1a1 is observed in similar frequencies across caste groups in north India. The only problem is zaka (Indo-Scythian) R1a1 as they are thought to be from the region inhabited by older R1a1 migrants. Therefore, their composition might have been similar.
d. Clustering for various castes
-> According to Bamshad et al. upper castes cluster together with East Europeans and lower castes with East Asians(Asian in the study). However, some of the later studies have shown conflicting results on this. One of the studies has found Indians forming genetic continuum from west Asia/East Europe to East Asian/SE Asia. Another has found Indians (upper and lower included) forming their own cluster and being significantly closer to Europeans than to East Asians. Of course, Europeans include West Asians which is rather absurd. However, all these show non-reliability of autosomal analysis. Probably, overemphasis of known markers of European population in the studies might be the reason behind it.

Semitic Introgression Theory(SIT) and Sahoo et al. (2006)
Also, studies can be used to prove some of the other theories too. Let us consider my theory. Keeping Austro-Asiatics and Dravidians out of it, I propose two main migrations that overlapped in the single word Aryan migration.

1. European Migration: Defining haplogroup R1a1. Migratin from European lands to South Asia via Central Asia. Period 5000 BCE to 2000 BCE. These people mostly came as refugees and labourers to present day Iranian and Indian lands. Indologist like Michael Witzel believes there could have been only few Indo-Aryan speaking migrants who spread their languages due to Elite Domination. I think that is only true for western and southern European countries.

Consider Greece. Greeks have R1a1 frequency around 10-15% same as that of Dravidians. That shows Elite Domination is responsible for the spread of an IE language in Greece. However, Indo-Aryan speaking population in north-west India and Pakistan carry this lineage at around 30-40%. That is a huge number. That probably shows European pastorals migrating to South Asia in search of greener pastures spread their language because of sheer numbers. Probably, were helped by IE-ised Aryan migration from west Asia as an elite society in the later stage.

2. Semitic Introgression: Defining haplogroups J2a and G2. Migrants from Iran and Caucasus. Also spoke Indo-Iranian languages. The self identification of these people is 'Arya'. The original language could have been different. However, the huge migration from eastern Europeans to eastern Iran and southern Caucasus changed the linguistic profile. These people heraled Vedic civilization that blended eastern European gods and classes with western Asian purity-pollution rules.

From Norse mythology it is clear that early PIE society had three fold varNa (colour) system or had three classes.
Vedic India had four fold varNa system
I have discussed about this in one of my previous post. We have already seen that herders position became low or became equal to that of serfs or zUdra

The Aryan Invasion Theory believes the natives became part of zUdra. However, SIT believes since the caste system with purity and pollution rules has nothing to do with original European society even the other eastern European migrants must have been degenerated into lower castes. It has nothing to do with racial purity of Europeans but rather deals with racial purity of West Asians.

Sahoo et al. (2006) study "Phylogeography of Mitochondrial DNA and Y-Chromosome Haplogroups Reveal Asymmetric Gene Flow in Populations of Eastern India" examines four castes from Orissa.

Brahmins (upper castes)
Karan and Khandayat (middle castes)- scribes(?) and Kshatriya
Gope (lower caste) - herders

The study makes an observation;
Analysis of Y-chromosomes revealed that the average
genetic distance between Orissa Brahmins and Eastern
Europeans (0.066) is relatively less than the distance
between Eastern Europeans and the Karan (0.098), Khandayat
(0.150), or Gope (0.067). Since both upper and lower
caste populations, i.e., the Brahmins and Gope, were
closer to Europeans and Central Asians, than were the
middle caste populations, the Karan and Khandayat, this
indicated that genetic distances have no correlation with
their position in the caste hierarchy. Similar findings were
reported by Bamshad et al. (1998) and Wooding et al.

Of course, Bamshad made some other observation after few years. A post at Eurasian Linguistics at yahoo group mentioned that scientists deliberately make controversial statements to attract public interest and funding(especially in population genetics field). Probably, the kind of people they want to attract and who would pour money probably could be gauged from Bamshad et al. (2001) study.

Brahmins and Gopes being close to east Europeans is entirely expected. Interestingly, Khandayat who became Kshatriya are overwhelmingly Y-haplogroup R2. And authors ascribe their origin to tribes.


Maju said...

That's interesting because IEs were primarily pastoralists (so it's logical that Gope castes are closely related). Nevertheless, I find intriguing why the rulers became priests instead of the traditional warrior/aristocrat position in which we find them in Europe. This seems a quite original evolution in the South Asian specific context. Just speculating, I can guess that IVC rulers were priests and hence the IE rulers adopted that status, while you don't find that situation anywhere in Europe at the time if IE invasions.

turd said...

Actually the truth is that, they aren't "Asian", they're more Australoid, which is a separate race, and they're more multiple migrations, so many of the Indian Aryans in the north are results when the first Aryan moved in with the rest and the second Scythian invasion was when the rest came afterwards

Manju Edangan said...

Your any definition of 'race' is as valid as any definition of 'god'.