Anthropology.net

If you’re reached your saturation coefficient with my coverage of population genetics, news of a 100,000 year old Homo from Henan, China should be welcoming. All I have so far is this press release, which is confusing. A quote from Li Zhanyang, an lead excavator with the Henan cultural relics and archaeology research institute, brings up some questions,

“The fossil consisted of 16 pieces of the skull with protruding eyebrows and a small forehead. More astonishing than the completeness of the skull is that it still has a fossilized membrane on the inner side, so scientists can track the nerves of the Paleolithic ancestors.”

I’m thinking somethings were lost in translation. First, fossils do not have eyebrows. Maybe a protruding brow ridge? That could be what they are trying to get at. Also, the article doesn’t say what membrane was fossilized within the brain case. My best guess is that it is the dura mater, the tough outer layer of the meninges that surrounds the brain. Even with the dura mater, it is hard to trace nerves from a Paleolithic fossil. One can probably trace the sulci and gyri and overall gyrification pattern imprinted from the brain, that will be useful in comparing the variation in the amount of fissures of archaic Homo brain.

Anyways, I’m super excited about this fossil find. No word on whether or not this fossils is Homo erectus or Homo sapiens. During this time period, two fossils come to mind that complicate assigning the taxonomy. First is, Jinniushan man, a 300k to 200k year old specimen that shows features of H. erectus, but with a endocranial volume similar to H. sapiens, as well as a overall thin cranial vault, expansion and rounding of the occipital and parietal region, the position of maximum cranial breadth, and overall facial morphology have resulted in Jinniushan being allotted to archaic Homo sapiens. Contending Jinniushan, are the Homo erectus looking Peking man fossils, which were lost in transit during World War II. These fossils are also from a similar time period.

This new Henan specimen is around 100,000 years old. Because of this date, I will very surprised if it is assigned as Homo erectus. Trinkaus’ 40k year old Tianyuan human also from Zhoukoudian, where the Peking fossils were found, would be awesome to compare. But the Tianyuan fossils can’t be used to compare these new Henan fossils, because the Henan collection is only of cranial bones. The closest things we have to cranial bones with the Tianyuan human is a mandible.

All hope is not lost, the endocranial volume from these new fossils can probably be calculated, which will give very good data on how to annotate this specimen. If the specimen is estimated to be an adult with a brain volume of around 1100cc or less, that would be really interesting!

If you don’t know already, I’m of Iranian decent. I was born in Tehran, but because of persistent socio-political instability in that region of the world, my family and I immigrated out of the country about 20 years ago. But just cause I live somewhere else doesn’t mean I’m not interested in my background. I’ve always been curious and inquisitive about my heritage. I’ve come to understand my mother’s and father’s lineage come from very different cultural backgrounds.

My mother’s family have been established Tehranians for quite sometime and because of the nature of big city life, their heritage has been mixed and lost. But if you look at members of my mother’s family, they are fair skinned and have blond hair with green or blue eyes. Often, they get mistaken for Europeans, which leads me to think they have a different heritage from my father’s side of the family. I’ve sequenced a short bit of my mtDNA and can only figure out that my maternal lineage has the haplotype H4 signature, which is very frequent in middle eastern populations, and not enough of a resolving feature to really make make any strong conclusions about where that half of me comes from.

What we know of my father’s family differs greatly. My dad’s parents hauled out of Lorestan and into Tehran. Lorestan is a western Iranian province smack dab in the Zagros Mountains. It is sometimes home to the Bakhtiari, a nomadic pastoralist group that you may have been introduced in your cultural anthropology learnings. The Bakhtiari regularly speak Luri, a language that’s classified as Indo-Iranian. Indo-Iranian languages are distinct from languages spoken by Semitic peoples, such as Arabic and Hebrew, if you want more information about this distinction check out Ethnologue.com.

Suffice to say, I got really interested to stumble upon an early online release paper from the Annals of Human Genetics, which investigates the, “Close Genetic Relationship Between Semitic-speaking and Indo-European-speaking Groups in Iran,” because it has tangents to at least half of my known heritage. Academics from the Max Planck Powerhouse of Evolutionary Anthropology and Tehran University collaborated on figuring out who the Bakhtiari are related to.

In order to carry out the study 99 people were sampled from a different province, Khuzestan, with almost 50 to 50 ratio of people from both ethnicities. The authors honed in on comparing the mtDNA HV1 sequences, eleven Y chromosome bi-allelic markers, and 9 Y-STR loci. STRs are a class of polymorphisms that, like microsatellites, consist of a repeated pattern of two or more nucleotides. The repeats are directly adjacent to each other and can range in length from 2 to 10 base pairs. They usually exist in the non-coding introns of genes.

Anyways, all these different loci show that the Iranian-Arabs share close relatedness of to the Bakhtiari as well as with neighboring geographic groups, irrespective of the language spoken. Haplogroups J2 and G are especially intriguing because they are found in really high frequencies in Bakhtiari and Iranian-Arab populations. Like I mentioned above, the Bakhtiari are a distinctly different cultural group that speak a Indo-Iranian language which does not belong to the Afro-Asiatic linguistic family that classify Semitic speaking Iranian-Arabs. Many cultural barriers have been formed to keep the Bakhtiari way of life unique, and one of them is language. So it doesn’t make sense that these two linguistically separate groups share two haplogroup signatures in such a disproportionally high frequency.

A comparison of Iranian-Arabs to other Semitic speaking groups showed that Semitic-speaking North African groups are way more distant genetically from Semitic-speaking groups from the Near East and Iran. The above illustration documents this. Haplogroup L is almost nonexistent east of Iraq, despite the fact there are Semitic speaking populations in foothills of the Zagros mountains in Iran.

Now, I said that was surprising because often language is a big barrier, as recently expressed by Razib with the Slavs as an example. In Iran however, a different situation exists. There is a lack of significant differentiation between west Asian Semitic-speaking and Indo-European-speaking groups indicates that language has not been a substantial barrier to gene flow in this part of the world. But this leads me to wonder about the origins of Iranian-Arabs, if they are genetically less similar to other Semitic speakers, doesn’t that imply they were ‘cultural converts’?

P.S., If you do read the paper, take note of the disclaimer the authors put about inscribing identity.