The Przewalski horse: a prehistoric horse who lived through the Ice Age (Part 3)


N.B.: This clear chronostratigraphy may be helpful to situate the various dates, periods and events discussed in this article.


Equids first appeared on the earth 4-4,5 millions years ago[1] and went through tremendous evolution phases to acquire their contemporary appearance[2]. Horses originated in North America and subsequently migrated to South America and Eurasia through Beringia, which connected the continents during prehistoric glaciation periods[3]. Eurasian Steppe MapHorse populations significantly fluctuated in size over the past 2 million years in phase with colder and warmer periods[4], and the latest research suggest that climate has been “a major driving force” in megafauna population dynamics, including wild horses, over the past 50,000 years[5]. This latter period roughly corresponds to the second half of the Late Pleistocene (126,000-11,700 years ago) and is concurrent to the last glaciation commonly known as the Ice Age. During this period and until the end of the Last Glacial Maximum (LGM), which lasted from 26,500 to 20-19,000 years ago[6], horse populations boomed due to the expansion of their favored open steppe-type habitat to the detriment of woodland as a result of colder temperatures and a drier climate[7]. They roamed the entire Eurasian steppe belt (see above map)―which nowadays stretches from Moldavia eastward across Ukraine, Russia, Kazakhstan, China, Mongolia, and is bounded by Siberian taiga and broadleaf forests to the North and by deserts to the South―and far beyond to the West.

Horse head, Mas d'Azil, France

Horse head, Mas d’Azil, France / Credit: Edouard Piette.  This image is in the public domain.

This broad prehistoric range is corroborated by archeological and paleontological findings. Horses are present on two thirds of Eurasian archeological sites dating from this period[8]. In Asia, rock pecked and engraved representations as well as horse remains were unearthed in various locations including the Mongolian Altai, particularly the site of Tsagaan Sala-Baga Oigor[9], the South Siberian Altai with the sites of Kara-Bom, Ust-Karakol or Okladnikov[10], and the Yellow River Basin in China. Cave wall engravings and paintings were also discovered in Europe[11]. In southern France, the Grottes de Lascaux (Dordogne) display no less than 364 horse figures[12]―the animal most depicted by far―estimated to be 17,000 years old while those of the Grotte Chauvet (Ardèche) were sketched some 31,000 year ago, making them the oldest ever chanced upon worldwide[13]. Located in northern Spain, the Cueva de Altamira exhibits 15,000 to 14,000 year old illustrations of equids[14].

Horse paintings at the Grotte Chauvet, France

31,000 year old horse paintings at the Grotte Chauvet, France which recently became UNESCO World Heritage / This image is in the public domain.

Western Europe was also rich in decorated tools and other relics including a 35,000 year old ivory carving of a horse found in the Swabian Alps (Germany)[15] and a 13,000 year old horse head sculpted in a reindeer antler fetched from the Grotte du Mas d’Azil (France). These are, of course, just a few examples on a much longer list. 

Horse at the Grotte de Lascaux

A horse from the Grotte de Lascaux displaying Takhi features. / This image is in the public domain.

It has been said that Takhis once inhabited south-western Europe because exterior features of current specimens appear to be recurrent in European prehistoric parietal art. This conclusion, based on look-alikes between creatures that lived thousands of years apart, cannot alone be relied on. Paleontological findings, which in this case are determining, suggest otherwise. Late Pleistocene fossil bones corresponding to Przewalski horses were discovered in Asia, particularly in China from the Liaodong Peninsula to Quinghai, north-east and south-west of the current city of Beijing and in the Dzungarian Basin, as well as Kazhagstan[16]. By contrast, those retrieved in Western, Central and Eastern Europe so far belong to other horse species such as Equus gallicus, Equus latipes and Equus antunesi[17]. Therefore, to date, there is no tangible paleontological evidence that Przewalski horses ever lived in Europe, which confirms Central and East Asia as the cradle of their independent evolution from 72-38,000 years ago.

European Vegetation from the LGM to the mid-Holocene

Source: Europe during the last 150,000 years, Compiled by Jonathan M. Adams, Environmental Sciences Division, Oak Ridge National Laboratory, USA

After the LGM, temperatures started warming up again―save the brief yet abrupt colder Younger Dryas episode from 12,800 to 11,600 years ago[18]―until the end of the Ice Age 11,700 years ago. In Western and Central Europe, the arid vegetation of the past millennia was rapidly and durably replaced first by woodland, and then by increasingly dense forests[19] which significantly downsized the horses’ prefered open habitat. The vegetation of Western Russia, Siberia, Kazakhstan, Northern China and Mongolia shifted to a combination of moist steppe, forest-steppe and semi-desert[20], thus maintaining better conditions than Europe for the horses. Meanwhile, humans were expanding across Europe and Asia, gradually overlapping the horses’ range.

Between the end of the LGM and the final years of the Ice Age, wild horses experienced a decline in genetic diversity[21] and their numbers dwindled in the whole of Eurasia[22]. They went extinct in most of Western and Central Europe[23] or retreated eastward to Ukraine, Russia and the rest of the Eurasian Steppe where herds remained abundant throughout this transition into overall warmer climatic conditions[24]. These trends in wild horse population dynamics were induced by climatic and anthropogenic pressure although the role played by each one in the process and the causal links between the various factors involved remain largely unclear[25].

Asian vegetation 25,000-15,000 years ago

Source: Eurasia during the last 150,000 years, Compiled by Jonathan M. Adams, Environmental Sciences Division, Oak Ridge National Laboratory, USA

Two species of wild horse, which may not have looked identical on the entirety of their respective range, are known to have lived through the end of the Ice Age into our present era, the Holocene: the Tarpan horse in Central and Eastern Europe as far as the Russian steppes and the Przewalski horse in Central and East Asia and parts of Siberia[26].


Continue reading about the Przewalski horse: Part 1 I Part 2 I Part 4 I Part 5 I Part 6 I Part 7 I Part 8 I Part 9 I Part 10 I Part 11 I Part 12


REFERENCES – [1] Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse, Orlando L. et al., Nature, 4 July 2013. [2] Le cheval : monture, nourriture et figure: L’évolution des Équidés, in Études mongoles et sibériennes, centrasiatiques et tibétaines, Véra Eisenmann, 41 (2010). [3] Le cheval : monture, nourriture et figure: L’évolution des Équidés, in Études mongoles et sibériennes, centrasiatiques et tibétaines, Véra Eisenmann, 41 (2010), §4. [4] Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse, Orlando L. et al., Nature, 4 July 2013. [5] Species-specific responses of Late Quaternary megafauna to climate and humans, E. D. Lorenzen et al., Nature, 17 November 2011, Vol 479, pp 359-365. [6] The Last Glacial Maximum, P. U. Clark et al., Science, Vol. 325, No. 5941, 7 August 2009, pp. 710-714. [7] The Fossils of the Przewalski’s horse and the climatic variations of the Late Pleistocene in China, in Equids in Time and Space – Papers in Honor of Véra Eisenmann, Deng Tao, Oxbow Books, 2006. How mammoths lost the extinction lottery, Ewen Callaway, Nature, published 2 November 2011. [8] Species-specific responses of Late Quaternary megafauna to climate and humans, Nature, 17 November 2011, Vol 479, pp 359-365. [9]  Late Pleistocene and Early Holocene Rock Art from the Mongolian Altai: The Material and its Cultural Implications, Esther Jacobson-Tepfer, Arts 2013, 2, pp 151-181. [10] The Pleistocene Peopling of Siberia: A Review of Environmental and Behavioural Aspects, Anatoly P. Derevianko et al., Indo-Pacitif Prehistory Association Bulletin 25, 2005 (Taipei Papers, Vol. 3). [11] Przewalski’s Horse: The History and Biology of an Endangered Species, Lee Boyd, Katherine A. Houpt, p 5. [12] Centre d’etudes prehistoriques de Terra Amata [13] Grotte Chauvet: la plus ancienne au monde, Le Figaro, published on 7 May 2012. [14] Museo de Altamira [15] Przewalski horse information board at the Haus zur Wildnis, Ludwigsthal, Germany. [16] The Fossils of the Przewalski’s horse and the climatic variations of the Late Pleistocene in China, in Equids in Time and Space – Papers in Honor of Véra Eisenmann, Deng Tao, Oxbow Books, 2006. Horse Domestication and Conservation Genetics of Przewalski’s Horse Inferred from Sex Chromosomal and Autosomal Sequences, Lau et al., 2008. The Archaeology of China: From the Late Paleolithic to the Early Bronze Age, Li Liu, Xingcan Chen, Cambridge University Press, 2012, pp 111-112. [17] Le cheval : monture, nourriture et figure: L’évolution des Équidés, in Études mongoles et sibériennes, centrasiatiques et tibétaines, Véra Eisenmann, 41 (2010), §28, §32. [18] Paleoclimate Reconstruction / Younger Dryas Oscillation, Global Evidence, S. Björck, Elsevier B.V., 2007. [19] Europe during the last 150,000 years, Compiled by J. M. Adams, Environmental Sciences Division, Oak Ridge National Laboratory, USA. [20] There is however no definite consensus regarding Asian vegetation distribution during the LGM and its aftermath: Eurasia during the last 150,000 years, Compiled by J. M. Adams, Environmental Sciences Division, Oak Ridge National Laboratory, USA. [21] Species-specific responses of Late Quaternary megafauna to climate and humans, Nature, 17 November 2011, Vol 479, pp 359-365. [22] The Horse, the Wheel, and Language: How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World, David W. Anthony, Princeton University Press, pp 197-198. [23] Le cheval : monture, nourriture et figure: L’évolution des Équidés, in Études mongoles et sibériennes, centrasiatiques et tibétaines, Véra Eisenmann, 41 (2010): §25. [24] Przewalski’s Horse: The History and Biology of an Endangered Species, Lee Boyd, Katherine A. Houpt, p 6. The Horse, the Wheel, and Language: How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World, David W. Anthony, Princeton University Press, pp 197-198. mtDNA and horse domestication: the archaeologist’s cut, in Equids in Time and Space – Papers in Honor of Véra Eisenmann, Marsha Levine, Oxbow Books, 2006. [25] Species-specific responses of Late Quaternary megafauna to climate and humans, Nature, 17 November 2011, Vol 479, pp 359-365. The Horse, the Wheel, and Language: How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World, David W. Anthony, Princeton University Press, pp 197-198. [26] Le cheval : monture, nourriture et figure: L’évolution des Équidés, in Études mongoles et sibériennes, centrasiatiques et tibétaines, Véra Eisenmann, 41 (2010): §26.

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