Many people know about the large beasts that wandered Europe and Asia during the last ice-age (Pleistocene megafauna to you, natch), but few realise that these animals were the architects and beneficiaries of a giant habitat that no longer exists anywhere in the world.
Mammoth steppe; the name seems to allude to both the size of the habitat and the animals that roamed across it. In the period of the Mammoth both the North Sea and Bering Strait were not yet submerged and so a chilled grassy plain rolled unbroken from the British Isles through Siberia; all the way to the Yukon Territory of Canada. Across this steppe habitat we once had vast herds of animals that would make Africa blush: reindeer, yaks, bison, horses, giant undomesticated cattle, woolly rhinoceros, Irish elk, and of course, Mammoth. All of which were predated on by cave lions, sabre toothed cats, cave hyenas, short-faced bears and more. These animals were all the more impressive when it is considered that to conserve heat animals nearer the earth’s poles generally are larger than their equivalents we see at the equator (Bergmann’s rule).
Steppe habitat is characterised by being cool and dry, allowing grasses and shrubs to grow but with too little rainfall to allow trees to flourish. Over approximately the last 2 and a half million years the world has been in a regular state of change, with the cooler glacial periods interspersed with times such as the present, where it is comparatively warm and wet. During these occasions the steppe habitat is known to have contracted as it was possible for trees to grow, thus vastly changing the groups of animals found there as more forest-dwelling groups came in. The lions of the plains were replaced by the wolves of the forest.
There have been some suggestions that the steppe habitat was actually created by the large herbivores that lived on it. It is known that in the African savannahs elephants can be vital in preventing the encroachment of trees such as acacia onto the savannahs, by their regular browsing and demolition of any trees that grow. If this is the case for modern day pachyderms, why not their ancient cousins? It has actually been suggested that the extinction of species of North American mammoth and mastodon around 11,000 years ago caused such increases in vegetation on the continent that global CO2 levels dropped enough to trigger our most recent ice age. To me this presents an interesting idea (and one I’d be curious to hear an experts views on): when the subject of bringing Mammoths back to life is bought up, the retort ‘theres no mammoth steppe for them’ is inevitably used. But if they aided the creation of this habitat before, could they potentially do so again? De-extinction is controversial (and for many good reasons), but does somehow set the imagination ablaze.
A study published this May has focused on how these oscillations between different habitat types effected the interactions between the animals of Eurasia. It appears that wolves may have endured these cycles in habitat due to their greater ability to scavenge, whilst the large cats such as cave lions were more specialised to predating on reindeer; creatures of open spaces whose numbers fell in interglacial periods when tree-cover increased. It also appears that each predator’s degree of specialisation on reindeer was higher in Europe, where they were coexisting with Neanderthals, the close cousins of modern humans that focused their efforts on mammoth and horse species, forcing other predators to focus their efforts on other prey.
All of these species coexisted over many thousands of years in the areas which a great proportion of humanity exists today. To me it is incredible to think that just a few tens of thousands of years ago our world would be so different-the UK as part of the European continent, and where I am sat typing this likely at one point the site of battles between lions and great herds of reindeer, wolves hunting giant Irish elk, and even Neanderthals hunting mammoth. Though we cannot see all of this with our own eyes, these are the sights that our ancestors would have observed as they made their first tentative steps into such areas, a wild open land filled with vast game and enormous predators, perhaps even interactions with people greatly like us but able to hunt formidable mammoths, who even at times mated with us. Though it is foolish to wish for what often becomes an idealised version of Eden, it is fantastic to think what riches these lands have seen.