Abstract: The genomic changes underlying both early and late stages of horse domestication remain largely unknown. We examined the genomes of 14 early domestic horses from the Bronze and Iron Ages, dating to between ~4.1 and 2.3 thousand years before present. We find early domestication selection patterns supporting the neural crest hypothesis, which provides a unified developmental origin for common domestic traits. Within the past 2.3 thousand years, horses lost genetic diversity and archaic DNA tracts introgressed from a now-extinct lineage. They accumulated deleterious mutations later than expected under the cost-of-domestication hypothesis, probably because of breeding from limited numbers of stallions. We also reveal that Iron Age Scythian steppe nomads implemented breeding strategies involving no detectable inbreeding and selection for coat-color variation and robust forelimbs. ... The 14 ancient genomes reported here have strong implications for the horse domestication process. First, it has recently been discovered that a now-extinct lineage of wild horses existed in the Arctic until at least ~5.2 ka and significantly contributed to the genetic makeup of present-day domesticates (14,15). The timing of the underlying admixture event(s) is, however, unknown. Using D statistics, we confirmed that this extinct lineage shared more derived polymorphisms with the Sintashta and especially Scythian horses than with present-day domesticates (Fig. 2B). The domestic horse lineage, thus, experienced a net loss of archaic introgressed tracts within the past ~2.3 ky.Librado et al., Ancient genomic changes associated with domestication of the horse, Science 28 Apr 2017:Vol. 356, Issue 6336, pp. 442-445, DOI: 10.1126/science.aam5298 See also... Middle Ages: rotten time to be a spotted horse
Thursday, April 27, 2017
Sintashta and Scythian horses came from Hyperborea
Figuratively speaking of course. The relevant paper is behind a paywall at Science here. But the supplementary info PDF is freely available here. The press release from the lab that did the research is here.
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Or perhaps not figuratively.
There's still a line of the old, eurasian 'prewalski' existing. Known to have survived both the LGM and the YD at the Atlantic facade we may find the horses of Lascaux to match pretty well to the still existing "Fjord-horse".
This is a direct branch of the old, palaeolithic stock, known to have populated the Scottish and the Scandinavian highlands, along with the Fenno-Balto-Russian inland, during the early Holocene. Along with the 'first farmers' and the dynasty/ies of 'farming highlanders' (R1a).
It's cousine-lines can still be found on the larger and smaller islands outside of Norway, as ell as the Kurgan steppes. Meanwhile the stemfathers and mothers would survive and reproduce throughout the industrial revolution, as well as the post-modern acaademia - in and around the fjords and valleys of the Scandianvian Peninsula...
http://www.fjordhorseinternational.org/joomla/images/handbook/05_breed%20history.pdf
There's still a line of the old, eurasian 'prewalski' existing, who had survived both the LGM and the YD at the Atlantic facade.
No there isn't.
The so called wild ponies at the Atlantic facade are only superficially similar to Przewalski horses. Otherwise they cluster with modern-day domesticated horses.
Yes, sorry - I should say "Tarpan".
In terms of todays genetic they are both clearly different from the Prewalski, which seems to be the 'outlier'.
Here's a 11.100 year old sample of the Eurasian "Ekwos", from Denmark:
https://en.wikipedia.org/wiki/Wild_horse#/media/File:Equus_ferus.jpg
That's cool - the early Scythian groups were pioneering in these very cold, harsh. environments, so introgression from the endemic wild horse would make sense.
More on the ancient arctic horse and changes in horses to present day:
http://siberiantimes.com/science/casestudy/features/f0187-truly-amazing-scientific-discovery-on-adaptation-of-yakutian-horses-to-cold/. As "diverged from modern horses as humans are from Neanderthals, he said".
So how much of the reduced archaic introgression in modern horses will be from an incompatibility process, like is postulated for majority Sapiens Eurasians having reducing % Neanderthal since the Upper Paleolithic (and an apparently similar process in ancient majority Neanderthal for minority Sapiens ancestry), against how much will be from ongoing admixture (genes from Arabian horse, etc)? Generation time for horses is about half human, so it is only about twice the reproductive time to do it in.
@Matt
I'd be skeptical here.
The loss of archaic ancestry through time in both the human cases and in the horse might have nothing to do with selection against incompatibilities.
For the sapiens case, we know that there has been a major increase in Basal Eurasian ancestry in Eurasia in the last 10-15,000 years, and this component lacks archaic introgression.
As for the horse, it could simply be that domestic horses with very little archaic ancestry were later introduced into the breeding population.
Off-topic
42 Whole Genome and Y-chromosomal sequences from diverse Indian tribal and non-tribal populations, including the Jarawa and Onge from the Andaman Islands:
https://www.ebi.ac.uk/ena/data/view/PRJEB11455:
Andamanese whole-genome sequences (BAM and FASTQ files)
https://www.ebi.ac.uk/ena/data/view/PRJEB16019:
Continental Indian whole-genome sequences
https://www.ebi.ac.uk/ena/data/view/PRJEB19598:
Y-chromosome vcf files
The Article:
https://link.springer.com/article/10.1007%2Fs00439-017-1800-0
I read that paper. It's mostly garbage. Seems like it's trying to make it out as if Indo-Aryan languages came to South Asia from Anatolia during the Neolithic. The authors are just making fools of themselves.
The wide use of domesticated horses by many not-IE cultures from Botai in the east to Tripolye in the west makes it difficult to determine PIE by the use of horses only.
Is the Arctic Horse the same as the previously proposed robust Forest Horse ?
Karl_K said...
"For the sapiens case, we know that there has been a major increase in Basal Eurasian ancestry in Eurasia in the last 10-15,000 years, and this component lacks archaic introgression."
Are there any numbers to support this? I know Basal Eurasian ancestry increased, and archaic ancestry decreased, but I thought that the ice-man had higher archaic ancestry than modern Europeans. If this is true, then did the additional Basal Eurasian ancestry arrive since then?
Garvan
@Garvan
The Iceman's Neanderthal levels have been re-examined several times, and it is rather a low level compared to other Eurasians.
@Garvan
Here is a quote from John Hawks on the subject:
"Later analyses have made clear that our initial estimates of Neandertal ancestry in the Ötzi genome are overestimates. The source of the overestimation was sequencing and alignment errors in the ancient genomes."
@Garvan
"Basal Eurasian ancestry explains the reduced Neanderthal admixture in West Eurasians."
http://www.nature.com/nature/journal/v536/n7617/fig_tab/nature19310_F2.html
@Karl, actually I am a bit skeptical also. IRC Fu's study of Ice Age Europe found a reducing level not by Basal populations ancestry alone - http://www.nature.com/nature/journal/v534/n7606/fig_tab/nature17993_SF1.html / https://hms.harvard.edu/sites/default/files/assets/News/2016/images/may/NeanderthalAncestry.jpg - but would be good to see retested without BEu populations and with BEu as a control. Could still be due to mixture with "Crown Eurasians" with varying levels of Neanderthal admixture anyway though. Seems like there Has to be some effect of Neanderthal incompatibility, otherwise why Neanderthal ancestry deserts in genic regions? but can that really drive such a strong effect over the whole genome (inc. non-genic regions).
@Matt
Most of the early high Neanderthal levels are from 2 or 3 individuals that had very small, if any, direct input into modern populations.
Most of the purge in the Crown Eurasian coding regions must have been very rapid, within a few generations, and the rest was just genetic dilution by groups lacking as much admixture.
The sample size between 50,000 and 15,000 years ago is absurdly low to make these kinds of conclusions. A solid GWAS takes thousands of people to see any meaningful statistics.
Good news on the Russian Steppe for Przewalski's horses! http://www.rferl.org/a/endangered-horses-back-on-russian-steppe/27607786.html
Interestingly the Scythian Horses show something South German/Austrian about them. And most of those breeds with closer connection to the Scythian Horses are classified as Large Ponies or Small Horses...
So did the Scythians trade with Celts in that area or did Germanic tribes pick up some Scythian Horses near the Baltic/Poland area and bring it to the Alps ?
So Scythians mostly liked Dun and Palamino coloured horses.
The Scythian horses were from Altai and Tuva regions (Sintashta mare was bay, the Scythian stallions included one cream, two black, two spotted, four bay, and six chestnut). Sintashta mare and four Scythian stallions were MSTN heterozygous (causing muscular hyperthrophy).
The strong front limbs of these ancient Steppe horses must be associated with winter-pasture practice of tebenyovka (from Turkic verb "tebu", "to kick"), which is the horses kicking the snow with front legs to get vegetation from under the snow crust. Tebenyovka is practiced mostly in Kazakhstan, Mongloia, and Yakutia these days, roughly the same region where Sintashta and Scythian horses lived.
The Arctic extinct lineage is quite literally Hyperboreal, as these sceletons were unearthed in Taymyr Peninsula near the shores of Arctic Ocean. On PCA ( http://www.pnas.org/content/111/52/E5661.full ) the Taymyr horses clustered with Mongolian breeds (as well as with a subset of rare European breeds) but I don't think that the magnitudes of Taymyr admixtures have been reported.
So that big aDNA paper coming today or what? :) .
I don't know what's happening exactly. There are rumors of an "epic" ancient DNA paper coming this week, but the week is almost up.
So maybe, just maybe, we'll see something soon after Reich's talk, perhaps at bioRxiv? Or not.
The behemoth mate?>
The Behemoth is due very soon. So it might well be.
If that's the case we will also get some more Yamnaya aDNA., going to be a feast ! ...
EastPole said;
"The wide use of domesticated horses by many not-IE cultures from Botai in the east to Tripolye in the west makes it difficult to determine PIE by the use of horses only."
Looking at the Eurasian north during the Holocene - from western Iberia to eastern Siberia - we find no more than TWO ancient language-families, i.e. I-E and Uralian.
The spread of domesticated plants and animals can clearly be related to the same area and the same period of time.
The earliest spread of these domestics seem to be the goats, sheep and pigs, which start occuring in populations generally considered to be "hunter-gatherers", such as the Ertebolle/PWC.
The spread of the horse-cultures and the cattle-cultures often go together, but not always. Just like the Icelanders and the Faeroe islanders the Mongols and Tibetans keep horses (and goats), but rarely cows (or pigs).
Inbetween both of them we find the oldest (known) horses where the last mammoths died, at the shores between the English Channel and the South-Western Baltic, 11.100 yrs ago (link above).
For some funny reason we find the oldest, post-glacial (aur)oxes and cows in the same area, in Scania dated 11.000+ yrs old. The skeletons of a 9.500 year old aurochs from Denmark was found in complete condition, strongly indicating an intentional burial.
https://en.wikipedia.org/wiki/Aurochs
A selection from these "aurochses" seem to be the origin of the Holstein- and Herford-cattle and other land-races;
http://www.ancient-origins.net/news-evolution-human-origins/enormous-auroch-skeleton-found-ness-brodgar-neolithic-site-002208
Besides the highland-races of Scotland, Scandinavia, Central Europe and the Asia. https://en.wikipedia.org/wiki/Aurochs#/media/File:Bos_primigenius_map.jpg
Mesolithic burials of dogs, even with gravegoods, have been found within well-known graveyards on both sides of the Baltic.
http://www.sarks.fi/fa/PDF/FA31_25.pdf
As the domestication, selection and specification of the grey-wolf started more than 30.000 years ago, it's no wonder that also goats, pigs, cattles and horses had been tamed, selected and bred well before what's known as «the neolithic».
http://www.bioone.org/doi/abs/10.5252/az2013n2a3
A thorough comparision of European horses from ENE-BA shows that spesific breeding of horses were in full swing on various locations in Northern Europe already when the early farmers made their first Funneled Beakers.
http://www.bioone.org/doi/abs/10.5252/az2016n1a2
Concerning wheels, there's still no older known example than the 5.150 yrs old chart-wheel of ash-wood from the Ljubjana marshes – among 6.000 years old mould for bronze-axes. (The worlds oldest known tin-bronze is found in the same region, dating 6.500 years back.) The oldest known oxcharts are depicted on 5.300+ yrs old pottery from Bronice, Poland – found together with remains of an aurochs that had done quite a lot of pulling.
The worlds oldest wooden trackways are still from Ireland and the SW Baltic, with Campenmoor in NE Germany as the oldest; 6.835-6.715 BP. The oldest known stonepaved roads - used for frequent wagon-driving – has been found along the southern coast of Scania - dated around 4.000 yrs ago. The road from the old, bronze-age harbour outside of Malmo was used through some centuries, leaving traces showing a standard wheel-width of 88-90 cm – a common standard throughout iron-age and well into the middle-ages.
One may beg to question the common narrative created by Dr. Anthony, after an idea of Maja Gimbutas, using the kurgans of the well-known, ancient horse-culture of the eastern steppes as a sign of 'ancient origins' – from which we're supposed to find the first horses as well as the oldest wheels and the very origin of the IE languages. Given the above facts, there's NO archeological evidence left to explain a steppe-migration to Europe, as the facts are (all) pointing in the exact oposite direction – FROM the Baltics and towards the Ukrainian and Pontic steppes – and thus Iran and India as well as the Black Sea and the eastern Med.
http://oldeuropeanculture.blogspot.no/2014/03/togher-wooden-trackways.html
worth remembering imo that dogs etc were used to drag/pull loads before horses so wheels don't necessarily mean horses
or even wheels initially
http://www.voga.org/Dog_Sled_Trips.jpg
@Grey
Yes and the Travois could have been even more effective within Muddy conditions of Europe. The Irish used the Travois into the early 1900s.
Grey,
Wheeled car-ts and wag-ons have been pulled by oxen and horses, basically. At times by goat-bucks.
Solid sliders – such as travois and sled-ges - are also used behind horses, while ligther, more sophisticated ski-sledges are found behind dogs and reindeers. Until the boreal farmers came about, using their cold-blod horses - or even elks - to pull lumber out of the winter-woodlands.
Fast-moving ski-sledges are known from the Early Mesolithic, already.The oldest known is from Heinola, Finland, dated 10.000 BP. Here's a reconstruction made from a somewhat younger sledge, excavated from a combware-site in Lapinlax:
http://www.kansallismuseo.fi/sv/Image/4731/kk-49-rekirekonstruktio.jpg
It's known that the population that survived the last glacial maxima (LGM-YD) in NW Europe became the pioneering populations that explored and repopulated northern Eurasia - using boats, skis and sledges. We also know that their norther bracnhes had wolfdogs (huskies) and reindeers at their disposal. As the southern cousins, within the milder climate of the Baltic Ocean, could utilize oxes, horses and bucks – no less than 11.100 years ago.
Considering the estimated mutation-rate of huskies, from greywolfs, at 35.000 yrs, we may safely presume that the «art of domestication» was long at work already during the Paleolithic age.
Compared to the skills and effort needed to domesticate one or more grey-wolfs a domestication of wild goats, horses and reindeers are mere childplay. Besides being far less challenging and time-consuming it's also much more rewarding – in terms of food- and tool-production.
Which is why some have interpretated some famous cave-paintings from Paleolithic Europe to show signs of «proto-domestication». The possibility can obviously not be excluded, as the fist proves of sledges – for dogs and/or reindeers - show up together with the mesolithic pioneers – in the I-E myths remembered as procreating heroes (giants, gods) - along with skis, boats and paddles.
As modern genetics keeps enlitgthening old questions we may wonder, along with John Hawks and others, if not the 45.000 year old ancestors to the existing Europeans - after no less than 20.000 paleolithic winters north of the 60th paralell - had developed both skis and sledges, as well as solid fuhr-coats and snowshoes – already. Not the least to get along with their huskies and keep them domesticated – to endure the final cold-boost as the old, giantic glaciers of the Eurasian mountain-ranges finally shrunk and broke, to slip and slide away...
http://johnhawks.net/weblog/reviews/early_modern/arctic/pavlov_2001_arctic_europe.html
http://johnhawks.net/weblog/reviews/ancient-genomes/ust-ishim-fu-2014.html
But all the propaganda that diversity is good. How can it cause harm?
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