Iberomaurusians descend from a unique Sub-Saharan African lineage: Ancestral North African (ANA)

  I've been away for some time but one thing that's always stuck with me are the results of the Iberomaurusian (Taforalt) samples from the original Loosdrecht et al. paper [1] that published them and the later results from the Dzudzuana pre-print by Iosif Lazaridis et al. [2]

A two-way admix-ture model, comprising Natufian and a sub-Saharan African population, does not significantly deviate from our data (χ2 p ≥ 0.128) with 63.5% Natufian and 36.5% sub-Saharan African ancestry on average (table S8).

  

As quoted above, the original paper appeared to posit—though with only a modest fit—that the Iberomaurusians were essentially within the range of about 40:60 for Sub-Saharan:Eurasian ancestry by trying to model the Iberomaurusians as a two-way admixture between something Natufian-like and something Sub-Saharan that very intriguingly had broad SSA affinities. Seeming part West-African, East-African and even various sorts of SSA Hunter-Gatherer in its affinities:

These results can only be explained by Taforalt harboring an ancestry that contains additional affinity with South, East and Central African outgroups.

Whereas, upon finding the Dzudzuana samples from the Caucasus, that appeared to be an early form of Anatolian type Hunter-Gatherers and farmers a new model was put forward by Lazaridis et al.—once again with a rather modest fit (z-score of 2.4)—where the Iberomaurusians are instead modeled as close to 50:50 for Sub-Saharan:Eurasian ancestry:

They also, as you can see, shifted the narrative backwards in that it was most likely an Iberomaurusian-like population that contributed ancestry to Natufians rather than the other way around. Their percentages of Sub-Saharan-related and Eurasian ancestry in Iberomaurusians were also struck by another unrelated paper that mostly offhandedly touched upon the Iberomaurusians [3]:

This paper also landed on a more or less 50:50 Sub-Saharan:Eurasian background for the Iberomaurusians as you can see above, and I'm inclined to agree with it and Dzudzuana preprint in that their results are very consistent with how Iberomaurusians cluster on a global PCA between Sub-Saharan and Eurasian populations:

From looking at the above PCA they appear to cluster almost exactly the way Tigrinyas do in terms of distance between "purely" Eurasian populations—such as Western Hunter-Gatherers (Villabruna) and Anatolian Hunter-Gatherers (Pinarbasi)—and mostly "purely" Sub-Saharan groups such as Mbutis, the Gumuz and the Mota ancient DNA sample above. 

Their similarity in positioning to Tigrinyas is important because Pickrell et al. 2014 [4], as old of a paper as it is, did the best job I've ever seen of trying to calculate the total Eurasian ancestry of various populations across Africa such as Tigrinyas and had them at about 50%:

Its results are so good that they even, oddly enough, align somewhat closely with Somalis and Tigrinyas' mtDNA results where the former are at about 35-40% for Eurasian mtDNA lineages and Tigrinyas are at 50-55% which roughly fits even the autosomal variation I've seen among various commercial samples over the years where—barring outside recent admixture—Somalis to me seem 38-40% and Tigrinyas about 50-52%, though I'm not as sure with Tigrinyas since I've seen much less of them.

At any rate, the study did a good job compared to many others before or after because it utilized ALDER, a method that detects how much Eurasian ancestry entered African populations and when, rather than just assuming a simple one-time event. This allowed them to separate different waves of admixture rather than lumping everything together. They also reconstructed the ancestral Eurasian source instead of using modern populations like Sardinians or Europeans, which can distort results. 

By doing this, they provided a more accurate estimate of true Eurasian ancestry in African populations rather than forcing them into comparisons with groups that don’t fully represent their ancient genetic makeup. 

Finally, they recognized that bad reference choices can make ancestry "disappear." Studies before the Dzudzuana preprint failed to detect anything remotely Sub-Saharan related in populations like Natufians or as much Sub-Saharan related ancestry as there likely really is in Iberomaurusians because they compared them to the wrong groups such as Yorubas, Dinkas, the Mbuti or whomever else who may not be relevant to the type of SSA ancestry these populations actually carried. 

Pickrell and his colleagues avoided this sort of pitfall, making their results much more reliable than most and theirs is the only study I've ever seen where the percentages actually almost perfectly match a given population's global PCA position in respect to where they sit between Eurasians and Sub-Saharan Africans:

The results you see above are my own concoction using R and David Wesolowski's Global25 PCA coordinates. I calculated ancestry proportions by measuring the distance of each population to two reference clusters—one Sub-Saharan and one Eurasian—using mean PCA coordinates. The closer a population is to one cluster, the higher its assigned ancestry from that group, creating a proportional estimate of SSA vs. Eurasian ancestry.

The Sub-Saharan cluster in this case was represented by Mota, the Gumuz, and Mbutis, whereas the Eurasian cluster was represented by the previously mentioned WHG and Anatolian HG samples (AHG). I find it quite remarkable how I was able to so closely match Pickrell's results. In my opinion, much of the difference is attributable to the minor Eurasian ancestry in the Gumuz. I would not be shocked to see an almost 1:1 match between my results and Pickrell's if we ever have a "pure" AEA population to include among the SSA cluster.

It’s always encouraging when distinct methodologies yield similar results and this to me suggests Iberomaurusians were indeed roughly 50:50 Sub-Saharan:Eurasian with a slight skew toward the latter, as indicated by the Dzudzuana preprint, the Shum Laka paper, and the PCA positionings.

But moving on from that, you might wonder why I refer to Ancestral North African (ANA) ancestry as "Sub-Saharan" admixture. The Dzudzuana preprint and Shum Laka paper appear to theorize that the ANA lineage—if it existed— may have originated and spent much of its history no farther south than the Sahel, making "SSA" somewhat of a misnomer. While this might be true geographically, genetically, it is very much a Sub-Saharan population:

Above are a public simulated ANA component I encountered being used around the anthro-sphere from an unknown source (possibly made using Genoplot) and my own concoction in R. 

Funnily enough, I initially attempted to reconstruct ANA following Loosdrecht et al.'s ~65% Natufian-like and ~35% Sub-Saharan model whilst trying to explain Iberomaurusians' clustering but instead noticed this population—albeit with a poor fit—looked more like it contributed ancestry to both Natufians and Iberomaurusians with AHGs looking more like they fit the bill for the other side of Iberomaurusians' roots:

Generated using a Monte Carlo Simulation technique via the VahaduoJS tool

 That led me to try a different approach: instead of assuming Iberomaurusians were a fixed proportion of different ancestries, I used linear algebra to infer the missing population. I considered their PCA clustering position, the clustering position of AHGs, and calculated where another population must have been positioned to explain Iberomaurusians' pull away from AHGs:

ANA = Iberomaurusian + λ(Iberomaurusians − AHG)

Solve for that using something like R or Python and you should be able to get my final simulated ANA population's coordinates (it is the one used in the PCAs above):

My_Simulated_ANA,-0.494675,-0.00507719999999998,-0.0769332,-0.091086,-0.018835,-0.0725678,-0.1372456,0.0376134,0.2645316,-0.0786172,0.0414416,-0.0735542,0.1736056,-0.0870324,0.1799378,-0.067753,-0.027589,-0.1310216,-0.2921226,0.0829396,-0.064087,-0.2577662,0.1478732,-0.0187496,0.0461032

 

And what's incredibly interesting about this simulated sample I managed to put together is that it plainly clusters like a Sub-Saharan population and—like the 63.5% Natufian and 36.5% ANA based simulation and the public ANA simulation—it shifts Loosdrecht et al.'s model around in that both Iberomaurusians and Natufians look more like varying mixtures between something Anatolian Hunter-Gatherer related and this component rather than Iberomaurusians looking Natufian-like admixed:

Despite the poor fit for Natufians and the overdone fit for Iberomaurusians—we will surely need more appropriate samples such as Dzudzuana, real ANAs and ancient DNA from Egypt—quite interesting results because I effectively came to the same conclusion as the Dzudzuana pre-print before rereading and refreshing my memory on their findings and did so via a totally different methodology.

From the supplemental materials of the Dzudzuana pre-print

Again, always encouraging when differing methodologies point in the same direction like this. In both my PCA clustering of it and in the Dzudzuana pre-print it clusters plainly like a Sub-Saharan component, albeit like one that seems to perhaps have elevated affinities to Eurasians in a manner similar to but greater than Mota in displaying something of a pull toward Eurasians mostly along the y-axis of the following PCA:

 I strongly suspect that this is because—as the Dzudzuana pre-print's qpGraph essentially depicts—it is a cousin to the AEA cluster often discussed on this blog. A component that makes up most of the ancestry in Mota as well as the modern Dinka and Gumuz and even more so than this component ANA might have remained related to the Proto-Eurasians longer.

Nifty but perhaps simplified and not wholly accurate illustration of the Out-of-Africa migrations from Wikipedia

I'm sure those of you well-versed in population genetics are well-aware that all the populations outside of Africa including Native Americans, Pacific Islanders and Australasians appear to descend from a single population that expanded out of Africa sometime between 50,000 to 75,000 years ago: the "Proto-Eurasians".

This bottleneck may have formed in Africa itself before they left and I ultimately suspect, whatever ANA is, it probably represents a population that may have remained a sister population to these Proto-Eurasians right up until the last second. In a way Basal Eurasian before Basal Eurasian, but since it doesn't seem to have participated in the Eurasian bottleneck unlike Basal Eurasian it remains a firmly "Sub-Saharan" component in appearance:

And I would say it is possibly the source of most of the SSA ancestry we've always seen across the Middle-East, North-Africa and wider Mediterranean prior to the ancient DNA revolution when we were heavily dependent on global and regional ADMIXTURE runs. You will quickly notice that when ANA or a seemingly ANA admixed population such as Natufians or Iberomaurusians are introduced to a modeling of various MENA and Mediterranean peoples' ancestries their previous AEA and West-African (WA) affinities greatly depress:

I would venture to say that some populations, as you can see above, possibly never had AEA or WA admixture. It was all perhaps just ANA related ancestry being misattributed.

Then on the other side of things we now find populations such as Natufians, Neolithic Levantines and Iron-Age Egyptians who previously couldn't be modeled as part SSA being able to now show such ancestry because we found the unique SSA population we needed in the form of these hypothesized ANAs and they finally explain why groups such as Natufians and those Egyptians have a plain as day SSA pull in global PCAs:

I would strongly argue that—barring the interesting but unrelated things going on with East pulling groups such as Mal'ta boy, Ust-Ishim and the Han—you simply cannot pull away toward SSA populations on the x-axis and away from WHGs and AHGs in the manner above without possessing some sort of SSA ancestry and I suspect that, whatever ANA is, it may have existed along some sort of admixture continuum with AHGs from the southern Levant to what is now Morocco in different forms. Time and ancient DNA results will tell.

If and when this ANA group is found I personally don't doubt it will be shown to have originated and spent much of its time no more south than the Sahel. In fact, the same is likely true for AEA which only appears more south than modern Sudan in an admixed form such as in the case of Mota. But, in the end, both ANA and AEA clearly cluster like populations that did not participate in the Eurasian bottleneck just like any other "SSA" group.

References

1. Loosdrecht MV, Bouzouggar A, Humphrey L, Posth C, Barton N, Aximu-Petri A, et al. Pleistocene North African genomes link Near Eastern and sub-Saharan African human populations. Science. 2018;360(6387):548-552. doi:10.1126/science.aar8380. Available from: https://doi.org/10.1126/science.aar8380

2. Lazaridis I, Belfer-Cohen A, Mallick S, Patterson N, Cheronet O, Rohland N, et al. Paleolithic DNA from the Caucasus reveals core of West Eurasian ancestry [preprint]. Cold Spring Harbor (NY): bioRxiv; 2018. doi:10.1101/423079. Available from: https://doi.org/10.1101/423079

3. Lipson M, Ribot I, Mallick S, Rohland N, Olalde I, Adamski N, et al. Ancient West African foragers in the context of African population history. Nature. 2020;577(7792):665-670. doi:10.1038/s41586-020-1929-1. Available from: https://doi.org/10.1038/s41586-020-1929-1

4. Pickrell JK, Patterson N, Loh P-R, Lipson M, Berger B, Stoneking M, et al. Ancient west Eurasian ancestry in southern and eastern Africa. Proc Natl Acad Sci U S A. 2014;111(7):2632-2637. doi:10.1073/pnas.1313787111. Available from: https://doi.org/10.1073/pnas.1313787111

R Scripts and other files for the PCAs, charts and ANA simulations: https://github.com/Awale-Abdi/Anthromadness_ANA_post

Simplified and shortened for complete laymen:

Based on the findings of a peer-reviewed paper, a groundbreaking yet-to-be-peer-reviewed paper, and my own data analysis that corroborates and attempts to build upon their findings, there appears to have been an ancient population from over 15,000 years ago in North Africa that genetically clustered with present-day "Black" Africans. This group likely contributed ancestry to prehistoric populations such as the Natufians, and further influenced the genetic makeup of  modern Middle Easterners, North Africans, and potentially other populations with Middle Eastern ancestral ties such as those in Central Asia, South Asia, and at least Southern Europe. More on this in future posts and with future ancient DNA that rolls in.

Comments can be made freely from now on

This is an unusual post, but I feel I owe some of you an apology. Years ago, I enabled comment moderation due to excessive spam (ads, sex-bots etc.) and low-brow comments like one insisting, "These results are wrong! Sudanese people can’t have more Eurasian ancestry than Habeshas," without any explanation...

As a result, I didn't notice some comments under my latest post from January until today and have dozens of older ones backed up. Since Blogger doesn’t send notifications, I simply missed them. It bothers me that thoughtful, inquisitive, and respectful comments—or ones where I might disagree with the author's respectfully shared opinion—got lost in this process.

So, moving forward, comments will no longer be moderated before appearing. I'll just check in every few weeks or months to remove obvious spam, offensive content (e.g., threats, racial slurs, excessive insults), or anything too low-brow—though I might leave some for entertainment value.

Apologies to anyone whose comments I missed, both recently and in the past.

Ancient Egyptian Old Kingdom DNA (2500-3000 BCE): 10% Sub-Saharan and no Iran-Chalcolithic

I have larger, more expansive posts in the works but I had to share this as yet another piece of quick, interesting findings that seemed to have not popped up on a lot of people's radars. Credit should go to a Somalispot poster by the username of Xareen for bringing it to my attention on there. We now have a Bronze-Age Egyptian sample thanks to the thesis of one Adeline Morez from Liverpool John Moores University.[1]

In her thesis she goes over a sample dated to ~2,868-2,492 BCE from the Nuerat cemetery just south of Beni Hasan in the Minya governorate of Upper Egypt and they found that this sample is about ~10% Dinka-like in its ancestry

NUE001 also carries ~10% ancestry similar to the one found in the 4,500-year-old Ethiopian genome, derived from the eastern sub-Saharan African component

That component has gone by many names over the years in the anthropology sphere. East-African (EA), Ancestral East African (AEA), "Nilo-Saharan", or simply "Dinka-like" as it makes up the vast majority of the ancestry of Nilo-Saharan groups such as Dinkas and the Gumuz above, as well as the Mota Hunter-Gatherer of Southern Ethiopia. It further makes up the vast majority of the Sub-Saharan African ancestry in modern Horn-Africans such as Somalis, Amharas, Oromos, Tigrinyas, Aris and Wolaytas who are mostly genetically intermediate populations between Middle-Easterners and groups such as the Dinka (see here).

It appears this Egyptian, unlike the Iron-Age Egyptians from 8 years ago [2], has a bit of this ancestry much like modern Copts do:

They also seem to lack or have very little Iran-Chalcolithic-related ancestry, unlike the later Egyptians of the Iron Age, with the author in my opinion correctly speculating that this is due to the later period Egyptians having significant admixture from Asiatic (Semitic-speaking) groups such as the Hyksos:

The Nuerat sample did not carry the Caucasus Hunter-Gatherer genetic component that started to spread across West Asia ~4,000 years ago and is widely spread in present-day populations. The presence of this component in Egypt is likely associated with admixture between local Egyptian populations and Bronze Age-related populations from West Asia. This admixture pattern might result from the dominance of Lower Egypt by Canaanite (Levantine) rulers during the Second Intermediate Period (ca. 1,650-1,550 BCE).

A group of West Asiatic foreigners, possibly Canaanites, labelled as Aamu (ꜥꜣmw), including the leading man with a Nubian ibex labelled as Abisha the Hyksos (𓋾𓈎𓈉 ḥqꜣ-ḫꜣsw, Heqa-kasut for "Hyksos"). Tomb of 12th-dynasty official Khnumhotep II, at Beni Hasan (c. 1890 BC).

So, it seems many of us who assumed Ancient and Pre-historic Egypt may have not had any Dinka-like ancestry were being premature in going off those Iron-Age genomes we got several years ago, if indeed this sample is representative and I see no reason to believe it is not. It appears that when the West-Asian migrants came in they brought with them not just significant Iran-Neolithic/Caucasus-Hunter-Gatherer type ancestry but they also diluted out the previously present Sub-Saharan ancestry.

This sample, if we can get it into David Wesolowski's Eurogenes Global 25 PCA should be extremely interesting to run for many populations including my own Horn-Africans as I strongly suspect it will prove quite representative of our non-Arabian MENA ancestors who consistently appear very similar to Natufians—with a slight Iberomaurusian shift—in G25 based runs:

I reckon this individual will essentially be that with ~10% Dinka-like ancestry. We'll see, and here's to seeing more ancient genomes from Egypt from around this period and earlier. 

References

1. Morez A. Reconstructing past human genetic variation with ancient DNA: case studies from ancient Egypt and medieval Europe [doctoral thesis]. Liverpool: Liverpool John Moores University; 2023. Available from: 

https://researchonline.ljmu.ac.uk/id/eprint/18979/

2. Schuenemann VJ, Peltzer A, Welte B, van Pelt WP, Molak M, Wang CC, et al. Ancient Egyptian mummy genomes suggest an increase of Sub-Saharan African ancestry in post-Roman periods. Nat Commun. 2017 May 30;8:15694. doi: 10.1038/ncomms15694. Available from: https://www.nature.com/articles/ncomms15694

3. Wikimedia Commons. Drawing of the procession of the Aamu group tomb of Khnumhotep II at Beni Hassan [Internet]. Available from: https://commons.wikimedia.org/wiki/File:Drawing_of_the_procession_of_the_Aamu_group_tomb_of_Khnumhotep_II_at_Beni_Hassan.jpg.

Simplified for total laymen:

About eight years ago, Iron-Age Egyptian genomes were analyzed, showing no detectable "Black" African ancestry, unlike modern Egyptians—both Muslim and Christian—who have such ancestry at usually a range of 10-20%. This led to the assumption that such ancestry was a later addition and largely absent in Ancient Egypt.

Media headlines sensationalized the findings, with some even falsely and absurdly claiming that Ancient Egyptians were "closer to Europeans" than to modern Egyptians, their direct descendants. This is misleading because mostly non-Eurasian admixed Africans are genetically quite distinct from Eurasians. Even if two populations share 90% of their ancestry, a small (~10%) amount of Sub-Saharan ("Black") ancestry can inflate genetic distance, making them appear more distant from a closely related group than other Eurasians are, even when those Eurasians (such as Europeans) share no ancestry from within the last 5,000 to 10,000 years or more with the group that lacks Sub-Saharan ancestry unlike the group that's 10% Sub-Saharan. To be fair, the researchers didn't necessarily sensationalize the findings like that—the media did.

However, this new data discussed above regarding an Old Kingdom sample suggests that migrations from the Levant (Palestine-Israel region)—possibly during the Middle Kingdom—introduced new Eurasian ancestry, temporarily diluting the earlier Sub-Saharan African component. 

So, Egypt seems to for now have had some minor but not negligible Black-African ancestry (~10%), lost it for a time due to migrations from Asia, then got it back through a mixture of intermixing with Nubians (likely what happened with Copts) and the Trans-Saharan Slave Trade (mostly what seems to have happened with the Muslims), the latter case of which brought some completely new Black-African elements such as West-African ancestry. The rest is nerdy stuff about the other strains of ancestry from the Middle-East the average person probably won't be that interested in but I'll be discussing in future posts so feel free to stick around if you're intrigued.

Early Cushites rode Oxen?

It's been a minute so I thought I'd come back with a quick and interesting post. A few years ago I caught something presented in the findings of Sada Mire that left me somewhat bemused. In her findings at Dhambalin she says:

One of the hunting scenes depicts two hunters together, one standing and another hunter sitting on an animal, perhaps a horse, and holding a bow and arrow in position to hit antelopes surrounding him. Horses are still found/kept in Somaliland. [1]

Yet this makes little sense because the Dhambalin site is pre-historic by Horn African standards, dating to around 5,000 to 3,000 years ago according to her own paper [1]. This is important because domesticated horses originally come from the Eurasian Steppe where they were first domesticated by the people of the Botai Culture about 5,500 years ago [2]:

They only begin to appear in the Middle East after this by about 4,200 years ago from the Eurasian Steppe. [2] This is important because the Middle-East would have been where domesticated horses would have to spread to the Horn from and, unsurprisingly, the earliest known examples of horse domestication in the Horn so far date later than this to the Aksumites from about 2,000 years ago. [3] [4]

In the Somali Peninsula in particular, horses may have been introduced even later. The linguistic evidence implies as much at least, as the Somali word for "horse" (faras) is a loanword from Arabic [5], indicating that horses were possibly introduced during the Islamic period, approximately 1,400 years ago or after.

The gist is that these depictions could not have been of horses if the site indeed dates to around 5,000 to 3,000 years ago. At that time, domesticated horses, much like domesticated camels [6], were not present in the Horn of Africa. 

Instead, the animals kept by Horn Africans' ancestors at this time would have consisted of cattle, goats, sheep, and donkeys [7], as well as shepherd or hunting dogs often depicted in the cave-paintings across Somalia. These were the animals they brought with them as they seemingly migrated into the Horn from what is now Sudan and Southern Egypt [7]:

So, how could these Cushitic pastoralists have been depicting the mounting of horses? Well, if the depictions are not the people who made them simply being fanciful, I suggest that the answer is the following:

Footage of Baggara Arabs riding cattle

The man and his child you see above who are riding an ox belong to the Baggara Arab people of Chad and Sudan. Baggara = Baqara/بقرة in Arabic which means "cow", hence the group's name. They are aptly named after cattle because of their peculiar tradition of riding them. 

This is relevant because the Baggara people appear to be quite influenced by Cushitic pastoralists who once expanded into what is now Chad and Western Sudan around 4,000 to 3,000 years ago before being absorbed by waves of Chadic and Nilo-Saharan speakers whom modern Arabic speakers such as the Baggara descend from. [8] This even appears to show itself in the ancestral make up of the Baggara:

(see notes section for details on chart)

I myself, as a layman, have also noticed Cushitic roots in their material culture and would not be shocked if trained anthropologists with more time and resources noticed far more. Like many nomadic macro-cultures, Cushitic nomads have their own characteristic tents the way the nomads of the MENA region use poled goat-hair tents ("Bayt al-sha'ar" in Arabic which means "House of Hair") and the nomads of the Eurasian steppe use Yurts/Gers. Cushites' mobile dwelling of choice was and is the domed mat-tent ("Aqal Soomaali" in the Somali language):

Bejas

Afars in Ethiopia

Somalis

Something the Baggara share in with Coastal Cushitic Pastoralists such as Bejas, Sahos, Afars and Somalis:

The mat-tent is a core part of Cushitic nomads' culture and was probably left behind by the ancient Cushitic speaking inhabitants of Chad after they were absorbed by the ancestors of now Arabic speakers like the Baggara as well as Nilo-Saharan speaking camel pastoralists like the Tobou:

From a linguistic point of view [8], Cushitic pastoralists also appear to have most likely been the earliest known source of pastoralism among these groups given that many of the words they left behind in the surrounding Chadic and Nilo-Saharan languages have to do with livestock such as cattle and the general pastoral way of life. 

So, the earliest known people the Baggara may trace their herding of cattle to would have been Cushitic speakers like those of the Somali Peninsula and here they are, to this day, living in the same sorts of tents those Cushitic speakers would have and seemingly tracing significant ancestry to them whilst probably displaying many other cultural influences I lack the time, resources and skills to notice. Who is to say their cattle riding is not one of them?

You probably understandably think I'm getting ahead of myself. But, there is another group of Cushitic influenced people whom we know got their pastoralist way of life entirely from Cushites and they too were known for the same peculiar practice:

Long before horses became the premier riding animals, oxen had filled this need. At least 150 years previously there were Khoikhoi riders on cattle on the south coast, and on the lower Orange River by 1661. From them, the Xhosa had acquired riding skills by 1686. [10]

As shown in the depiction above and supported by the quote, the Khoekhoe of South Africa displayed cattle riding long before the introduction of horses. This is important because we know that they got got their pastoral way of life from South-Cushitic pastoralists. These South-Cushitic pastoralists are known to have appeared in Kenya and Tanzania around 4,000 to 3,000 years ago where they are believed to have made contact with the Khoekhoe's ancestors and influenced them [11], after prior arriving in the Horn possibly as early 5,500 years ago [12][13].

In Khoekhoe's case we have known for about a decade through peer-reviewed population genetic studies that they trace ancestry to these ancient Cushitic speaking pastoralists. We furthermore have evidence of Cushitic linguistic and cultural influences noticed by anthropologists beyond just the pastoralism itself. [14] Right down to the mat-tent:

Due to all of this evidence, they are outright accepted by academics to have gotten their pastoralist way of life from Cushitic speaking pastoralists who expanded out of the Horn. And much like the Baggara seem to have, the Khoekhoe have also preserved the original cattle focused pastoralism of early Cushitic nomads; unlike Bejas, Sahos, Afars and Somalis whose ancestors shifted to camel focused pastoralism within the last 2,000 to 3,000 years seemingly due to influences from Arabia. [6] 

It might be a stretch but I think the pre-historic rock-art in Somalia is in fact depicting people riding cattle, particularly oxen as in the case of the Baggara and Khoekhoe, and that these two groups preserved this ancient practice the same way they preserved other elements of early Cushites' culture.

It weaves together quite nicely. We have pre-historic Cushites who appear in the Horn about 5,500 years ago depicting what is possibly cattle riding sometime between then and 3,000 years ago then we have two geographically distant groups—whose ancestors were influenced by them sometime between 3,000 and 4,000 years ago—showing the practice. While not completely open and shut, it seems plausible that pre-historic Cushites practiced cattle riding and possibly even mounted archery as shown in the cave paintings in Somalia:

One of the hunting scenes depicts two hunters together, one standing and another hunter sitting on an animal, perhaps a horse, and holding a bow and arrow in position to hit antelopes surrounding him Horses are still found/kept in Somaliland.[1]

If true, this is remarkable—as it means early Cushites practiced mounted archery before it emerged on the Eurasian Steppe during the Iron Age [15], making them the earliest known humans to do so. They may also have been the first to ride animals, as the evidence suggests they likely practiced cattle riding before 4,000 years ago, approaching 5,000 years ago, during their time in the Horn. This assumption being based on their migrations into Chad, Kenya, and Tanzania after the Horn* by 3,000 to 4,000 years ago, where they appear to have already carried this practice given the Baggara and Khoekhoe. 

If cattle riding originated earlier in Neolithic Sudan, before 5,500 years ago where the upper limit lies for their appearance in the Horn, they would predate the Botai culture as the first known humans to ride animals, and are at minimum their contemporaries if the range of cattle-riding's development falls within 4,000 to 5,500 years.

References

1. Mire S. The discovery of Dhambalin rock art site, Somaliland. African Archaeological Review. 2008. Available from: https://www.academia.edu/4080948/The_Discovery_of_Dhambalin_Rock_Art_Site_Somaliland

2. Librado P, Tressières G, Chauvey L, et al. Widespread horse-based mobility arose around 2200 BCE in Eurasia. Nature. 2024;631(819–25). https://doi.org/10.1038/s41586-024-07597-5

3. Finneran N. The archaeology of Ethiopia. Routledge; 2007. Available from: https://www.taylorfrancis.com/books/mono/10.4324/9780203821183/archaeology-ethiopia-niall-finneran?

4. Munro-Hay S. Aksum: An African civilisation of late antiquity. Edinburgh University Press; 1991. Available from: https://drive.google.com/file/d/0B2ARnUeK-Y8WSF9uVEo2OGpMSkk/view?usp=sharing&resourcekey=0-fdIdGXk_s_aNdrcaZJLdAA

5. Soffer G. 6000+ Arabic - Somali Somali - Arabic vocabulary. Gilad Soffer; n.d. Available from: https://www.google.com/books/edition/6000+_Arabic_Somali_Somali_Arabic_Vocabu/CHelBQAAQBAJ?hl=en&kptab=morebyauthor&gbpv=1&bsq=faras

6. Banti G. Strata in Semitic loanwords in Northern Somali. 2013. Available from: https://www.academia.edu/5529034/2013_Strata_in_Semitic_loanwords_in_Northern_Somali

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8. Blench R. The westward wanderings of Cushitic pastoralists: Explorations in the prehistory of Central Africa. 2008. Available from: https://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_7/divers2/010020136.pdf

10.  The Reins of Power: Equine Ecological Imperialism in the Seventeenth and Eighteenth Centuries. In: Riding High. Cambridge University Press; 2019. Available from: https://www.cambridge.org/core/books/abs/riding-high/reins-of-power-equine-ecological-imperialism-in-the-seventeenth-and-eighteenth-centuries/F217FC987506E0C727F496DBFA9664EE

11. Blench R. Language, Archaeology and the African Past. Cambridge: Altamira Press; 2005. Available from: https://drive.google.com/file/d/1iHR5WP2KKaQMpJG3j9X_loFus9s1DWO9/view?usp=sharing

12. Negash A. Regional Variation of the Rock Art of Ethiopia: a Geological Perspective. 2018. Available from: https://drive.google.com/file/d/12tObLKQiNK1gvXxRrYOQV9WE4DtIRYzx/view?usp=sharing

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14. Blench R. Was there an interchange between Cushitic pastoralists and Khoisan speakers in the prehistory of Southern Africa and how can this be detected? Presented at Königswinter, March 28-30, 2007. Cambridge: Kay Williamson Educational Foundation; 2008. Available from: http://www.rogerblench.info/Archaeology/Africa/Konigswinter%202007/Konigswinter%20paper.pdf

15. Holmes R. Horse Archers: The Feared Unit of Ancient and Medieval Warfare. The Collector. 2023 Sep 4. Available from: https://www.thecollector.com/horse-archers/

References for all unlinked images in the order they appear

1. Haaland G. Amballa, Lower Wadi Azum, Darfur Before. 1965. Available from: https://ubdarfur.w.uib.no/2013/01/27/photo-84-ubb-haa-33/

2. Haaland G. Western foothills of Jebel Marra, Western Darfur, Darfur Before. 1965. Available from: https://ubdarfur.w.uib.no/2013/01/27/photo-83-ubb-haa-70/

3. Haaland G. Lower Wadi Azum, Western Darfur, Darfur Before. 1965. Available from: https://ubdarfur.w.uib.no/2013/01/27/photo-80-ubb-haa-283/

4. Hemis. Chad Southern Sahara desert Ennedi massif Archei Toubou nomad camp, Alamy Stock Photo. 2011. Available from: https://www.alamy.com/stock-photo-chad-southern-sahara-desert-ennedi-massif-archei-toubou-nomad-camp-70372606.html

5. Hemis. Chad Southern Sahara desert Ennedi massif Archei Toubou nomad camp, Alamy Stock Photo. 2011. Available from: https://www.alamy.com/stock-photo-chad-southern-sahara-desert-ennedi-massif-archei-toubou-nomad-camp-70372630.html

6. Johnston K. Khoisan Natives Riding Pack Oxen In Africa In The 19th Century. From Africa. 1884. Available from: https://www.gettyimages.com/detail/news-photo/khoisan-natives-riding-pack-oxen-in-africa-in-the-19th-news-photo/188005112

7. Daniell S. Khoikhoi of South Africa dismantling their huts, preparing to move to new pastures—aquatint. 1805. Available from: https://www.smithsonianmag.com/science-nature/ritual-cemeteries-cows-humans-pastoralist-expansion-across-africa-180970683/

8. Ratzel F. Khoikhoi People Building Huts, Southern Africa, Illustration from "Volkerkunde," Bibliographisches Institut, Leipzig. 1885. Available from: https://www.alamy.com/stock-photo-khoikhoi-people-building-huts-southern-africa-illustration-from-the-133334548.html

Notes

The chart results are from using samples from the Eurogenes G25 datasets and the Vahaduo tool as explained over Eurogenes. I then plugged the numbers into a google sheet and made my chart. The Eurogenes samples in turn come from studies featuring Baggara Arabs, a Savanna Pastoral Neolithic sample from Hyrax Hill in Kenya 2,300 years ago (Cushitic Pastoralist), Naqab Bedouin B samples (Peninsular Arab), Dinkas (Nilotic), Yorubas (West-African) and Third Intermediate Period Egyptians (Iron-Age Egyptian) all to be found in the various studies the Eurogenes dataset draws its samples from (see Eurogenes blog post linked).

* They appear in the Horn before they seem to have been in Chad, Kenya and Tanzania but it's important to point out that Blench, probably correctly, assumes the migration into Chad was from Sudan rather than from the Horn.