Tag Archives: Africa

Pastoral rock art in the Horn of Africa; making sense of udder chaos

Pastoral rock art in the Horn of Africa; making sense of udder chaos

Seriously, this is the papers title. Unable to cut and paste any, I’ll copy out a few snippets:

Pastoral rock art appears to be a comparatively recent phenomenon in the Horn, spanning only the last four to five thousand years.

The only evidence for cultigens is from Lalibela cave near lake Tana in north central Ethiopia where Dombrowski recovered barley chickpea and legumes from levels dating to no earlier than 2,500 BP.

The archaeological evidence for cattle is largely restricted to dental fragments  from Gobedra and Lalibela in the Ethiopian highlands, lake besaka in the Southern Afar rift, Laga Oda on the Somali plateau near Harar and Gogoshiis Qabe shelter ar Buur Heybe, southern Somalia. None of these faunal remains date to earlier tha 3,500 bp. Clay figurines from the site of Hawlti show that Pre-Axumites were still breeding humpless cattle as late as the first to second century AD. The earliest evidence of a humped Zebu cow is in the form of a small figurine from the 2nd century AD early Axumite site of Zeban Kutur.

It has some info on the rock art in Somalia and Ethiopia, it’s from 1987, but as far as I know no earlier dates have been found in Ethiopia for domesticates. However, some dates fo finger millet and sorghum are older in the Arabian peninsula and India, becoming staples by 2000 BC.


Domestication of the donkey: Timing, processes, and indicator


Abydos donkeys in brick tombs.

Domestication of the donkey: Timing, processes, and indicator

Domestication of the donkey from the African wild ass transformed ancient transport systems in Africa and Asia and the organization of early cities and pastoral societies. Genetic research suggests an African origin for the donkey, but pinpointing the timing and location of domestication has been challenging because donkeys are uncommon in the archaeological record and markers for early phases of animal domestication are hard to determine.We present previously undescribed evidence for the earliest transport use of the donkey and new paleopathological indicators for early phases of donkey domestication. Findings are based on skeletal data from 10 ~5,000-year-old ass skeletons recently discovered entombed in an early pharaonic mortuary complex at Abydos, Middle Egypt, and a concurrent study of 53 modern donkey and African wild ass skeletons. Morphometric studies showed that Abydos metacarpals were similar in overall proportions to those of wild ass, but individual measurements varied. Midshaft breadths resembled wild ass, but midshaft depths and distal breadths were ntermediate between wild ass and domestic donkey. Despite this, all of the Abydos skeletons exhibited a range of osteopathologies consistent with load carrying. Morphological similarities to wild ass show that, despite their use as beasts of burden, donkeys were still undergoing considerable phenotypic change during the early Dynastic period in Egypt. This pattern is consistent with recent studies of other domestic animals that suggest that the process of domestication is slower and less linear than previously thought.

As the paper says at one point:

In the 1980s zooarchaeologists working in southwestern Asia found bones attributable to donkey from sites in Syria, Iran, and Iraq dating to ca. 2800–2500 B.C.

the oldest date at 4,800 BP is from the Iranian highlands. So logically the domestiction of the ass in Africa would date to a substantial amount before 2,800 BC, and given the rate of expansion of camels and other livestock I’d say 6,000 years would be more realistic.

The Making of the African mtDNA Landscape

The Making of the African mtDNA Landscape

Africa presents the most complex genetic picture of any continent, with a time depth for mitochondrial DNA
(mtDNA) lineages 1100,000 years. The most recent widespread demographic shift within the continent was most probably the Bantu dispersals, which archaeological and linguistic evidence suggest originated in West Africa 3,000–4,000 years ago, spreading both east and south. Here, we have carried out a thorough phylogeographic analysis of mtDNA variation in a total of 2,847 samples from throughout the continent, including 307 new sequences from southeast African Bantu speakers. The results suggest that the southeast Bantu speakers have a composite origin on the maternal line of descent, with ~44% of lineages deriving from West Africa, ~21% from either West or Central Africa, ~30% from East Africa, and ~5% from southern African Khoisan-speaking groups. The ages of the major founder types of both West and East African origin are consistent with the likely timing of Bantu dispersals, with those from the west somewhat predating those from the east. Despite this composite picture, the southeastern African Bantu groups are indistinguishable from each other with respect to their mtDNA, suggesting that they either had a common origin at the point of entry into southeastern Africa or have undergone very extensive gene flow since.

An old paper from 2002 that I’m posting for reference while I’m hunting down info on L3a.

Paragroup L3A
We here define two previously unlabeled subclades of L3A, L3f, and L3g. The lineages remaining within L3* represent ~20% of all L3A types in Africa. Although they are distributed throughout the continent, they reach the highest frequencies in East Africa, where they account for about half of all types from this region. This frequency profile suggests an origin for L3 in East Africa (Watson et al. 1997). This is supported by the evidence that the out-of-Africa migration, which took place from a source in East Africa 60,000–80,000 years ago, gave rise only to L3 lineages outside Africa.

Cattle before crops :The Beginnings of Food Production in Africa

Cattle before crops :The Beginnings of Food Production in Africa
In many areas of the world, current theories for agricultural origins emphasize yield as a major concern during intensification. In Africa, however, the need for scheduled consumption shaped the development of food production. African cattle were domesticated during the tenth millennium BP by delayed return Saharan hunter-gatherers in unstable, marginal environments where predictable access to resources was a more significant problem than absolute abundance. Pastoralism spread patchily across the continent according to regional variations in the relative predictability of herding versus hunting and gathering. Domestication of African plants was late (after 4000 BP) because of the high mobility of herders, and risk associated with cultivation in arid environments. Renewed attention to predictability may contribute to understanding the circumstances that led to domestication in other regions of the world.

An interesting pdf, that has a fair bit of information on Nabta Playa and how modern hunter gatherers transplant plants nearer to their homes, and pen wild animals to feed up for meat at social/ritual events. It’s insightful as to the reasons behind some pre-domestication behaviour. I agree with the observation that it’s the favoured/hard to find foods and not the bulk foods that seem to be more likely to be domesticated first. If I think about what I grow in the garden, it’s things like strawberries and tomatoes, for flavour, not as a bulk calorie source. It’s much easier to go out to fetch the bulk of my food, and it seems to be the same for hunter gatherers. I notice they omit that Grigson described the early cattle at Nabta as morphologically wild though.


The observation that wild animals are penned and fed up for special occasions may shed some light on the Nabta Playa cattle remains. There’s been a cattle cult in the area for a long time, and it makes sense that you’ll make sure that you have access to a bull to sacrifice/eat, rather than risk being empty handed on the big day. One of the other Saharan sites is thick with wild Barbary sheep dung so there is a precedent for penning wild animals in the area; a precursor to domestication. I suspect this is more likely to be what happened at Nabta Playa than a full domestication complete with dairying. There was a cattle cult at Catal Hoyuk in Turkey (site of the Turkish domestication of cattle), the same as in El Nabta, so the same incentive would have been on both groups to ensure reliable supply of the animals. However, so far the evidence isn’t great that it got beyond penning  for Nabta. One way to settle this one would be to sample the cattle from Nabta for mt DNA (if possible) to see if they are ancestral to the earlier cattle remains in Egypt and North Africa. A nice direct line back to Nabta into the early neolithic cattle would settle that debate.


The paper also has a good section on the domestication of African crops. It should be noted that some African crops turn up in Asia before they are found in African sites though, so I wouldn’t take the domestication dates at sites as gospel. An interesting (for me at least) observation is that wild grains are often not harvested with a sickle, but are hand stripped or knocked into a basket, which could mean the grains were being eaten in mesolithic Europea too (there’s pollen evidence for it, but plant material doesn’t survive the damp climate).

Phylogenetic and phylogeographic analysis of African mitochondrial DNA variation

Phylogenetic and phylogeographic analysis of African mitochondrial DNA variation
Sadie Anderson-Mann, March 2006

With mitochondrial DNA lineages tracing back more than 100,000 years, the genetic diversity
present throughout Africa is unparalleled. Within this continent, a wide array of different
mitochondrial haplotypes are found; as a result of the numerous demographic movements
that this region has witnessed, these have been differentially dispersed, some being
geographically localised whilst others are found over a large proportion of the continent.
Along with the Atlantic slave trade, the Bantu dispersals are the most recent of population
movements to have had significant effect on the genetic landscape of Africa, and are
associated with the distribution of several different haplogroups. Here, phylogenetic and
phylogeographic analysis of over 2,000 predominantly sub-Saharan African mtDNA
sequences has been carried out, through construction of reduced median and, where
necessary, median joining networks, based on mtDNA hypervariable segment 1 (HVS-I)

A big article that I will read sometime I don’t have food poisoning. It contains a lot of info about the Bantu expansion in it.

Are Africans genetically more vulnerable to HIV?

While reading up on the Duffy blood type the other day, I found this article..

Duffy antigen receptor for chemokines mediates trans-infection of HIV-1 from red blood cells to target cells and affects HIV-AIDS susceptibility.

Duffy antigen receptor for chemokines (DARC) expressed on red blood cells (RBCs) influences plasma levels of HIV-1-suppressive and proinflammatory chemokines such as CCL5/RANTES. DARC is also the RBC receptor for Plasmodium vivax. Africans with DARC -46C/C genotype, which confers a DARC-negative phenotype, are resistant to vivax malaria. Here, we show that HIV-1 attaches to RBCs via DARC, effecting trans-infection of target cells. In African Americans, DARC -46C/C is associated with 40% increase in the odds of acquiring HIV-1. If extrapolated to Africans, approximately 11% of the HIV-1 burden in Africa may be linked to this genotype.After infection occurs, however, DARC-negative RBC status is associated with slower disease progression. Furthermore, the disease-accelerating effect of a previously described CCL5 polymorphism is evident only in DARC-expressing and not in DARC-negative HIV-infected individuals. Thus, DARC influences HIV/AIDS susceptibility by mediating trans-infection of HIV-1 and by affecting both chemokine-HIV interactions and chemokine-driven inflammation.

If I understand this correctly, the Duffy negative individuals catch HIV easier, but it takes longer to kill them. Personally I think I’d prefer being less likely to catch it in the first place. According to the Times this means about 2.5 million Africans have HIV because of their Duffy negative blood.

Another Y chromosome study showing a back migration into Africa from Asia.

A back migration from Asia to sub-Saharan Africa is supported by high-resolution analysis of human Y-chromosome haplotypes.

The variation of 77 biallelic sites located in the nonrecombining portion of the Y chromosome was examined in 608 male subjects from 22 African populations. This survey revealed a total of 37 binary haplotypes, which were combined with microsatellite polymorphism data to evaluate internal diversities and to estimate coalescence ages of the binary haplotypes. The majority of binary haplotypes showed a nonuniform distribution across the continent. Analysis of molecular variance detected a high level of interpopulation diversity (PhiST=0.342), which appears to be partially related to the geography (PhiCT=0.230). In sub-Saharan Africa, the recent spread of a set of haplotypes partially erased pre-existing diversity, but a high level of population (PhiST=0.332) and geographic (PhiCT=0.179) structuring persists. Correspondence analysis shows that three main clusters of populations can be identified: northern, eastern, and sub-Saharan Africans. Among the latter, the Khoisan, the Pygmies, and the northern Cameroonians are clearly distinct from a tight cluster formed by the Niger-Congo-speaking populations from western, central western, and southern Africa. Phylogeographic analyses suggest that a large component of the present Khoisan gene pool is eastern African in origin and that Asia was the source of a back migration to sub-Saharan Africa. Haplogroup IX Y chromosomes appear to have been involved in such a migration, the traces of which can now be observed mostly in northern Cameroon.

I’m just to tired to focus on this right now.. I’ll read it later.

Click to images to see full size.