Galloping across the steppes

A team of horses (Equus caballus) slowly moving across the European steppes around 30,000 years ago. (Art by Tabitha Paterson)

Around 50 million years ago, long before the Epoch of the Twilight Beasts, a little mammal, Eohippus, scurried about in the forests of North America. This creature, about the size of an average dog, was the ancestor of the magnificent horse we know today. During this Period, called the Eocene, the environment and climate was constantly changing, and little Eohippus responded to adapt. Some species kept the paw like feet and just grew a little larger. Others lost a few toes altogether. Like the plants Eohippus fed from, horse evolution was a bushy tree of different species, some branches giving rise to new species, others evolutionary dead ends.

The horse that we know today, Equus caballus, evolved from the tiny little Eohippus. In one group, the little paw-like feet developed into a single hard ‘toe’, which we now know as a hoof. (If you run your hand down a modern horses leg, careful not to be kicked, you will feel  small bony structures either side of the ankle; these are called ‘chestnuts’ and are the rudimentary, diminutive,  proto-pony paws!) This solid, hard hoof allowed for rapid galloping across the plains of North America, and due to the land bridges of the Miocene and Pliocene Epochs, it’s believed that herds of horses galloped their way into Eurasia and Europe.

The horses of the Americas evolved in a slightly different way through the Pleistocene period, with the Hippidion species, which does not appear to have spread into Eurasia. Funny enough, with its name meaning ‘little horse’ the average Hippidion was the size of a small pony (although smaller variations have been found), with a distinctive flexible snout. Some 70% of North American fauna became extinct at the end of the Pleistocene, with the wild equines diminishing in body size, perhaps because of poor grazing and climate changes. No-one really knows if the extinction was due to dwindling vegetation from of climate changes or if human ‘overkill’ hunting methods contributed as well.

We know from beautiful artwork in caves such as Chauvet Cave, dating to around 30,000 years ago, that early humans must have looked in wonder at these herds of creatures. It is easy to imagine the freedom and thrill Ayla gets from riding her wild horse across the steppes in The Valley of Horses by Jean Auel (and equally easy to sympathise with Jondalar’s obvious embarrassment as he sits behind her on the horse and they ride it together!).

Although early humans hunted the horse for food, skins and bone, these big beasts must have also been appreciated for their grace and beauty, as the cave paintings and figurines convey a wonderful understanding of the horse’s elegant natural movements. One of the most fabulous sculpted pieces is the Vogelherd horse, with its neck arched proudly, carved some 32,000 years ago during the bitter cold of the Aurignacian period.

The steppes had the greatest variation of types, from the tarpan to the horse we now know as Przewalski’s Horse. The tarpan (Equus caballus ferus) is the true European Pleistocene horse, depicted in cave art.  Their small height (similar to that of a Exmoor Pony), belied a strength and capacity to survive some of the most challenging conditions of prehistory. They grazed the steppes and steppe/forest lands of Eastern Europe, where some of the subspecies appear to have increased in height to become the ancestors of the exquisite and ancient Akhal Teke breed. Little is known of the other subspecies of European wild horse which roamed freely from Spain to Russia, although we know there was a genotype which created the unusual ‘leopard spot’ horse colouring depicted on the walls of Chauvet  and Lascaux caves in France.

A sketch of a tarpan (Equus caballus ferus) the first true Pleistocene European modern horse. (Art by Tabitha Paterson)

The tarpan was usually a mousey grey colour, with black legs and muzzle and a dorsal stripe down its back, like many of the most ancient breeds extant today. The closest genetic relatives to Equus caballus ferus may well be the modern Exmoor, Dortmund and Konik. The last pure-bred tarpan died in 1879, in the Ukraine, plunging to its death down a ravine rather than accept being captured by humans, which in itself speaks volumes about the wild nature of these wonderful ancestors of the modern horse.

The remote steppes of Eurasia were also the last natural home of the other, perhaps better known wild horse of the Pleistocene, Equus ferus przewalskii; the Przewalkski wild horse.  One man, Dr Przewalksi, saved this horse from extinction, by breeding a number of the animals in captivity to preserve the lineage. With its distinctive golden coat, hogged mane and mealy muzzle, the Przewalski looks the epitome of the primitive wild horse depicted in mobilary art from the dawn of mankind. So unique are its looks that it was considered by many taxonomists to be a unique species in its own right. Research into mitochondrial DNA in 2009 suggests it is closely related to the modern horse, and doesn’t form a separate (or monophyletic) group. This hardy and stunning little pony is a true victor of the Ice Age, perfectly adapted for bitterly cold temperatures, drought and scant food supplies.

As a typically ‘horsie’ little girl, I can understand the awe they held, and as an adult its my own personal ambition to see the Przewalski horses in one of the sanctuaries now created for them across Europe. I admit my preference would be the spectacular Paläon centre in Schöningen, Germany, where a Pleistocene landscape has been recreated for these magical creatures! I can think of few things as fabulous as gazing at a creature whose bloodline is derived from Ice Age survivors and imagining how our own ancestors fell in love with them as much as we do today.

Written by Rena Maguire (@justrena)

Art by Tabitha Paterson (@TabithaPaterson)

Further reading:

Auel, J. M. (1987), The Valley of Horses. Cornet Books. 11th Ed. [Book]

Clutton-Brock, J. (1999), A natural history of domesticated mammals. Cambridge: Cambridge University Press. [Book]

Guthrie, D. (2003), ‘Rapid body size decline in Alaskan Pleistocene horses before extinction’, Nature, 426, 169–171. [Abstract only]

Kavar, T and Dovč, P. (2008), ‘Domestication of the horse: Genetic relationships between domestic and wild horses’, Livestock Science, 116, 1-14. [Abstract only]

Lau, A, et al. (2009), ‘Horse Domestication and Conservation Genetics of Przewalski’s Horse Inferred from Sex Chromosomal and Autosomal Sequences’, Mol. Biol. Evol, 26, 199–208. [Full article]

Levine, M. (2006), ‘mtDNA and Horse Domestication: The Archaeologist’s Cut’ in Mashkour’, M. (ed.), Equids in Time and Space. Oxford: Oxbow Publications, 192-201. [Full article]

Price, N (Ed). (2001), The Archaeology of Shamanism. London: Routledge. [Book]

Weinstock J. et al. (2005), ‘Evolution, Systematics, and Phylogeography of Pleistocene Horses in the New World: A Molecular Perspective’. PLoS Biol. 3.8 e241. doi:10.1371/journal.pbio.0030241 [Full article]