The lion (Panthera leo) can rightly claim to be the most oft-invoked animal in all of human culture. Whether praising someone as leonine or lion-hearted, or throwing them to the lions, the second largest of felines has the ability to evoke emotions that the tiger (Panthera tigris), leopard (Panthera pardus) and jaguar (Panthera onca) simply do not. This entwined history stretches at least as far back as the late Pleistocene (100,000 to 10,000 years ago) and possibly as far back as the late Pliocene (about 3.5mya), when the lion lineage first split from the other pantherine cats.
We tend to think of the lion as a quintessentially African animal and, indeed, this is where the vast majority of lions survive today. However, the tiny enclave holding around 400 lions, in the Gir forest reserve of India, hints at the expanses previously ranged by this majestic cat. If you were to travel back in time to 50,000 years ago, you would find lions in all of Africa (north and south of the Sahara), the Middle East, Europe, the Indian subcontinent (including Sri Lanka), Siberia, Alaska and North America as far south as Mexico. From the Cape of Good Hope to the isthmus of Darien, lions occupied a range greater than any other terrestrial mammal, except man (Fig. 1). It seems incredible to modern eyes, but the lion was an integral part of the European ecosystem right up until the Holocene (10,000 years ago to the present).
How did it get here? What did it look like? What did it eat? Why did it disappear? For all these questions, we are moving towards answers – answers that paint a fascinating picture of a vanished animal.
What do we know about the evolution of the lion? Quite a lot, thanks to the fact that the fossil record for this large carnivore is pretty good. The modern lion is the sister species to the leopard and jaguar (Fig. 2), which together make up the subgenus Panthera (the tiger is sufficiently different that it has its own subgenus – Tigris). Despite the obvious differences in adult pelage and morphology, the cubs of the three Panthera species are remarkably similar, all possessing rosettes, which are only lost in the lion on reaching maturity (and sometimes even then still faintly visible on the legs).
We know from molecular studies that this group split off from other pantherines around 2 to 3mya (Johnson et al., 2006). The best fossil representative we have for the base of this triumvirate is P palaeosinensis, from the Pliocene of northern China, a unique skull that blends features of all the Panthera cats (Mazak, 2010). After this, the first appearance of fossils that appear lion-like is at Laetoli, around 3.5mya, although whether these actually represent ancestral P leo, P pardus or some other offshoot is difficult to say (Turner and Antón, 1997).
It is not until the appearance of P leo fossilis in Europe around 500,000 years ago that we can be certain that the fossils are absolutely leonine in form. P leo fossilis, or the ancestral cave lion, was an enormous cat. Found at sites such as Bisnik cave in Poland (Marciszak and Stefaniak, 2010), Sierra de Atapuerca, Spain (Garcia et al., 1997) and Mauer in Germany (Wagner et al., 2010; and see Fig. 3), the ancestral cave lion was perhaps up to a quarter larger than the largest modern day lions. During the late Pleistocene, fossilis actually became slightly smaller, producing the true cave lion, P leo spelaea, which has been found in abundance in Europe, Siberia and Alaska – showing what an incredible range the species had. At some stage, fossilis even penetrated the Americas, crossing the Bering land bridge and becoming P leo atrox, the American lion (Barnett et al. 2009).
The ancestral cave lion must have been an imposing sight – in Europe, its only challenger to the title of apex predator would have been the sabretooth cat (Homotherium sp.). We know that sabretooths and the ancestral cave lion made it to Britain, as remains of both have been found in middle Pleistocene deposits in East Anglia (Lewis et al., 2010), which, at that time represented the north-westernmost peninsula of mainland Europe. The true cave lion was equally at home in southern England during the late Pleistocene. Remains of P spelaea have been found in many of the classic sites dating to this era (Fig. 3), including Kent’s cavern, Kirkdale and Wookey Hole (Dawkins et al., 1866). Incredibly, even underneath the giant lions that guard Trafalgar Square in London, remains of cave lions dating to the last interglacial have been found (Franks, 1960) – a rare case of nature imitating art.
Lions and humans
Lions are still often represented in human art. The ‘lions rampant’ and ‘lions passant’, familiar from heraldry, are far from the most ancient attempts at capturing the essence of the leonine. It is under-appreciated that the very oldest known example of figurative art (that is, art not depicting something found in the real world) is of a lion-headed human from the late Pleistocene site of Hohlenstein-Stadel in Germany (Fig. 4). This therianthrope is carved from mammoth ivory and has been radiocarbon dated to around 30,000 years BP (Vanhaeren and d’Errico, 2006). And it is not a one-off piece. Other lion-people (or “Löwenmensch”) have been unearthed from other sites in Germany (Conard, 2003), testifying to some important ritualistic importance for this were-animal in Palaeolithic European societies. What the cave lion meant to these people is now lost in time, but it clearly meant something important. Other groups even used the massive canine of the cave lion as a pendant in a necklace (Vanhaeren and d’Errico, 2006).