This is the first post of a series which will deal with a possible archaic origin of the Y chromosome C haplogroup in humans. The idea surfaced in my mind while looking at the migratory route purportedly taken by modern humans when they left their homeland in Africa some 60 to 70 kya. After crossing the Bab-El-Mandeb Strait at the southern tip of the Red Sea, they stuck to a coastal route and advanced into Asia along the shores of Southern Arabia. After crossing the Persian Gulf at the Strait of Hormuz, the old a group carrying the C haplogroup in their Y chromosomes took a Southeastern direction, towards South Asia, other groups went North and East. mtDNA haplogroup M also split at Hormuz from N, and took exactly the same Southern path towards South East Asia.
I recalled that Homo erectus had inhabited this part of the world and wondered if there was a link between these apparently disconnected events.
I prepared a map (below), showing this migratory route where the initial OOA episode is the blue arrow and the C haplogroup dispersal is shown in red arrows. The yellow shaded regions are those where C hg is currently found:
The Homo erectus territory is in green
Copyright © 2014 by Austin Whittall
Occam's razor to seek simple answers
The simplest explanation is this: humans are intelligent beings that follow corridors offering food, water and shelter. It is very likely that H. erectus took this coastal route because it offered all three elements and thus guaranteed survival. The modern humans that followed them 1.5 My later had the same needs and would have taken the same route if it continued to provide a competitive advantage.
So, it is not a coincidence but a logical series of factors that caused H. sapiens carrying haplogroups M (mtDNA) and C (Y chromosome) to follow the same path as H. erectus did one and a half million years earlier.
But there could be an alternative explanation to these coinciding dispersal routes: H. erectus carried the M and C haplogroups with them as they migrated along this route... and this post (and some others to follow) is the outcome. Yes, I must explain why I believe that these haplogroups even existed 1.5 Mya and were to be found in non-sapiens hominins...
The first to leave Africa
That our oldest ancestors evolved in Africa is not questioned (and it will not be questioned here either) because there is ample proof of ancient remains dating back several million years. The Australopithecines are undoubtably our most primitive relatives, and we evolved from them and their descent.
The appearance of an intelligent mind soon led to the manfacture of stone tools and the urge to discover new horizons beyond their original homeland. The existence of appropriate ecological setting and adequate resources to sustain them, enabled our hominin ancestors to move out of Africa and into Eurasia roughly 2 Mya.
The formerly accepted picture was that Homo habilis and their predecessors were too small and primitive to cope with the complexities of migrating out of Africa. Their Mode 1 flake and core stone tools (Oldowan industry) were too rudimentary. Furthermore, the dating of Asian sites showed that they were not older than 500 - 800 kya., long after the disappearance of H. habilis.
So it was their succesors, the H. erectus, who made it out of Africa first. They took their Mode 2 (or Acheulean) toolage with them into Western Eurasia yet those who went beyond India (crossing the "Movius line") and entering China and India, somehow did not use these stone tools.
But then a series of findings in Eurasia have upset this neat scenario:
- Israel. 'Ubbeidiya site, in the Jordan River valley. 1.4 - 1.6 Mya. Tools with Flake and Core Mode 1 similarities. [1][2]
- Dmanisi, Georgia. Crania, bones and tools (1.78 Mya) with Oldowan affinities or maybe even pre-Oldowan since many lack retouching. The remains are similar to the African H. erectus (known as H. ergaster) but have smaller crania and therefore closer to H. habilis. This suggests a pre-erectus dispersal: [3]
♦ Skull sizes from 546 cm3 to 730 cm3 vs. H. habilis' 509 to 687 cm3.
♦ Small bodied: 146 to 166 cm, 47 to 50 kg, similar to H. habilis but in the lower range of H. erectus. - Pakistan, Pabbi Hills, with a Pre-Acheulean assemblage of 2.2 - 0.9 My.
This of course upsets the previous picture: if the smallest and most primitive H. erectus remains are found in Georgia then, they may have evolved there from even earlier hominins (H. habilis), and dispersed from this point towards Africa (an Into Africa Migration) and Eastern Asia. Since Indonesian remains are about 1.8 My old, then the dispersal took place quickly. [4]
This means therefore not one or two, but multiple migratory waves: H. habilis OOA, archaic H. erectus movin on towards Asia. And maybe, even into Europe (1 - 1.2 Mya).
Mode 2 Acheulean tools are found in Africa 1.8 Mya, and later in the periphery, does this mean that they originated in Africa? : Isampur India (1.2 Mya), 800 kya in China and Ngebung, Java. Europe sees them 600 - 700 kya; Eastern Europe and the Caucasus is late (after 300 kya). [5]
This is under debate: the large flaked core (piece R001) from Riwat, Pakistan was dated [6][9][10] to the Olduvai event c. 1.8 Mya. It is different to the other tools from Africa, Europe or China. It is old yet clearly Acheulean and maybe even older than African tools.
This has suggested that Eurasia may have played an active role in the shaping of our hominin ancestors: with speciation taking place there and migrations back into Africa with subsequent dispersals just like happened with certain mammals: "more taxa migrating into than out of Africa" [7].
This would allow the African H. ergaster to have originated in Asia.
The Migratory Route
We can envisage a route from East Africa across Ethiopia and into Saudi Arabia: This would be the main exit route from Africa in an H. erectus OOA event. Yet no remains have been found, only Acheulean tools at two separate sites: one close to the Red Sea (Wadi Fatimah), another at Daw Ädmi. Unfortunately no dating is provided. [8]
As seen above there are tools but no remains in Pakistan; the next sites should be in India:
India
The earliest fossil remains and Acheulean handaxes in India are from Hathnora in Narmada Valley, Madhya Pradesh. The Middle Pleistocene (c. 500 kya) skull of an H. erectus was discovered there in 1982. [18]
The date is much later than other remains from sites in Western and Eastern Asia. So it is likely that H. erectus reached India 1 My before the Narmada remains.
Expansion after India
There are other H. erectus sites in Indian Subcontinent: in Nepal (Satpati) in the North, Attirampakkam in the South (1 Mya) and the centrally located ones at Hunsgi-Baichbal, Anagwadi and Godavari.
H. erectus continued advancing east, closed in by the Himalayas on the North reached current Myanmar. From here there is a split, in two directions, one North, into China, another South towards Indonesia.
The Southeast Asian H. erectus
Indonesia. It was on the banks of the Solo River in Java, that Eugene Dubois discovered the remains of the first H. erectus in 1891. He named the species Pithecanthropus erectus or "Upright ape man".
It is probably distinct from the African H. ergaster and the oldest remains are those found at Mojokerto (skull) 1.81 Mya and Sanigran (1.6 –1.7 Mya).
H. erectus thrived in Indonesia until quite recently: the remains from Ngandong and Sambungmacan in Java are the youngest H. erectus fossils ever found. They have been dated to between 40 and 70 kya. This means that they were coeval with the Homo sapiens that entered Australia and Southern Asia. [12]
These late H. erectus, when compared to those from other sites, are "the most derived population" [4] and have brain volumes larger than previous Indonesian H. erectus, closely approaching the mean values of extant Australian Aboriginals [13].
Their persistence until such recent times both here and in China (see below) is surprising and it raises the question of why did they disappear in Africa if they were so well adapted to survive?
Australia
No H. erectus fossils have been found in Australia. Nevertheless, robust H. sapiens remains showing possible signs of admixture were found there in 1982: the Willandra Lakes Hominid (WLH) 50. They date to between 12.2 and 32.8 kya and are clearly Human but with singular features: stron brows and thick cranium. [14]
They have a statistically significant [13] correlation with the Ngandong fossils and both may share a common ancestor with modern Native Australians. In other words they are linked to each other by "a reticulating evolutionary relationship" [13].
The Northeast Asian H. erectus
Other groups moved north, towards cooler climes in China and Korea.
South Korea, the Imjin-Hantan River Basins (IHRB) have yielded Acheulean biface handaxes. The dating of the sediments that contain them indicate that "the earliest hominin occupation of the IHRB may be slightly older than the 350 ka" [15]. Not tremendously old, but clearly pre-sapiens.
China a long persistence of H. erectus
The famous Peking Man, from the Zhoukoudian site close to Beijing, was discovered in the 1920s and named Sinanthropus pekinensis (Peking Chinese Man). The remains originally believed to be c. 300 ky old have been pushed further back: 750 kya.
China has several sites with archaic toolage: Bose, Luonan and the very ancient Nihewan site, at a high northern latitude, dated to a mean age of 1119 +⁄- 139 ka. [16]
As in Indonesia, Homo erectus survived until recently at the Lantian site close to Xi'an in Northern China; Acheulean assemblies dated to between 70 and 30 kya have been found there, suggesting the suvival of H. erectus there until " the later period of the late Pleistocene" [17].
Some comments
The idea of dynamic interacting groups of people, moving from place to place, even back-migrating if necessary, is much more exciting than the linear models so commonly found in the study of our ancestry, where admixture events were not even considered until relatively recently.
Clearly the paucity in fieldwork in Asia compared to Europe or Africa is one of the reasons for the lack of solid evidence regarding archaic remains and tools. The dating issues are perhaps complicated in Asia when compared to Africa due to soil conditions or climate.
Another factor to take into accunt is mindset; precocieved notions tend to fog the clear vision needed to identify remains or toolage as such: if you are not expecting to find tools 1.5 Mya, then you will never dig into strata of that age or older. Probably, as suggested by Dennell,[7] our australopithecine ancestors left Africa long before H. habilis (say 3 Mya), but nobody has bothered to investigate it.
Homo erectus was a versatile creature that adapted to a wide range of environments and survived for over 1.8 My. They surely admixed with modern humans (Isn't it surprising that H. erectus admixture has not yet been studied seriously - yes, there are some papers mentioning introgression with archaic "X" hominins, but not much refrence to H. erectus being "X") and perhaps were absorbed so thoroughly that they just disappeared.
Now, did they stop in China, or did they keep on marching north, into Siberia? They could cope with cold climates in North China, why would they stop there and not go on? I propose that they did, and reached America, but that is the subject of another post.
To be continued in Part 2
Sources
[1] Bar Yosef, O., Goren-Inbar, N., (1993). The Lithic Assemblage of 'Ubeidiya. A Lower Palaeolithic Site in the Jordan Valley. Institute of Archaeology, Hebrew University of Jerusalem
[2] Gaudzinski, S., (2004). Subsistence patterns of Early Pleistocene hominids in the Levant -taphonomic evidence from the 'Ubeidiya Formation (Israel)". Journal of Archaeological Science 31(1):65-75
[3] David Lordkipanidze et al., (2013). A Complete Skull from Dmanisi, Georgia, and the Evolutionary Biology of Early Homo. Science 18 October 2013. Vol. 342 no. 6156 pp. 326-331; doi: 10.1126/science.1238484
[4] Miriam Frankel, 28 July 2010, Notes from an excavation, News. Nature. doi:10.1038/news.2010.377
[5] Doronichev V.B., (2008). The Lower Palaeolithic in Eastern Europe and the Caucasus: A Reappraisal of the Data and New Approaches. PaleoAnthropology 107–157.
[6] Rendell, H., W. Hailwood, and R. W. Dennell. (1987) Magnetic polarity stratigraphy of Upper Siwalik Sub-Group, Soan Valley, Pakistan: implications for early human occupance of Asia. Earth and Planetary Science Letters 85:488-496.
[7] Robin Dennell and Wil Roebroeks, (2005). An Asian perspective on early human dispersal from Africa. Nature 438, 1099-1104 (22 December 2005) doi:10.1038/nature04259
[8] Michael D. Petraglia, Nick Drake, Abdullah Alsharekh, (2009). Chap. 8. Acheulean Landscapes and Large Cutting Tools Assemblages in the Arabian peninsula from "The Evolution of Human Populations in Arabia: Paleoenvironments, Prehistory and Genetics". Eds. Michael D. Petraglia, Jeffrey I. Rose. Springer, Nov 27, 2009.
[9] Hurcombe, L., Dennel, R., et al., (1994). Archaeological evidence for hominids in Northern Pakistan before one million years ago J.L. Franzen (ed.) 100 Years of Pithecanthropus, the Homo erectus problem. Courier Forschungs-Institut Senckenberg 171: Frankfurt. 151-155.
[10] Hurcombe, L. (2004). The lithic evidence from the Pabbi Hills. R.Dennell (ed) Early Hominin Landscapes in Northern Pakistan; Investigations in the Pabbi Hills. Oxford: BAR S1265, pp 222-291
[11] Anek R. Sankhyan et al., New Postcranial Hominin Fossils from the Central Narmada Valley, India. Advances in Anthropology 2012. Vol.2, No.3, 125-131
[12] Yuji Yokoyama, (2008). Gamma-ray spectrometric dating of late Homo erectus skulls from Ngandong and Sambungmacan, Central Java, Indonesia. Journal of Human Evolution, Vol. 55, 2, Aug. 2008, 274–277
[13] John Hawks et al., (2000) An Australasian test of the recent African origin theory using the WLH-50 calvarium. Journal of Human Evolution (2000) 39, 1–22, doi:10.1006/jhev.1999.0384
[14] Grün R., et al.,m (2011). Stratigraphy and chronology of the WLH 50 human remains, Willandra Lakes World Heritage Area, Australia. J Hum Evol. 2011 May;60(5):597-604. doi: 10.1016/j.jhevol.2010.12.001
[15] Kidong Bae, Christopher J. Bae and Kiryong Kim, (2012). The age of the Paleolithic handaxes from the Imjine Hantan River Basins, South Korea. Quaternary International 281 (2012) 14 -25
[16] Chun-Ru Liu et al., (2013) ESR Dating of the donggutuo Paleolithic site in the Nihewan Basin, Northern China. Geochronometria 40(4) 2013: 348-354. doi: 10.2478/s13386-013-0127-4
[17] Shejiang Wang et al., (2014). Newly discovered Palaeolithic artefacts from loess deposits and their ages in Lantian, central China. Chinese Science Bulletin Jan- 2014. 10.1007/s11434-013-0105-5
[18] Marie-Antoinette de Lumey and Arun Sonakia, (1985). Premier Decouverte D'un Homo Erectus sur Le Continent Indien A Hathinora, Dans la Moyenne Valle De La Narmada. L'Anthropologie (Paris), T. 89 n.1. 13-61
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2014 by Austin Whittall ©
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