As strange as it might seem, the living African and Asian elephants are only the remnants of what was once a very diverse array of proboscideans. In the not-too-distant past elephants and their closest relatives occupied Africa, Europe, Asia, North America, Central America, and South America, but almost all of them had perished by about 10,000 years ago.* Of these recently-extinct forms the most iconic was the woolly mammoth, Mammuthus primigenius, which was covered in long coats of shaggy hair. They were cold-weather mammoths, inhabiting chillier regions than their North American cousin the Columbian mammoth (Mammuthus columbi), and during the Pleistocene they ranged over much of the northern hemisphere.
*[There were some remnant populations here and there until about 4,000 years ago, but most species of recent fossil elephants were either gone or greatly reduced in number by this time. They disappeared along with many other large mammals such as giant ground sloths. The cause of this Pleistocene mass extinction is still being hotly debated.]
In a new paper published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology scientists Diego Alvarez-Lao, Ralf-Dietrich Kahlke, Nuria Garcia, and Dick Mol have extended the range of the woolly mammoth through the description of a 30,000-40,000 year old site in southern Spain. This Pleistocene fossil site, just south of the city of Granada, represents the southernmost extent of the woolly mammoths’ reach in Europe. The site itself is not new. It had been excavated during the 1980′s, but unfortunately much of the recovered material was either lost or scattered through museum collections. New material has continued to come out of the site since that time, however, and this has allowed the scientists to confirm the existence of its woolly Pleistocene inhabitants.
As yet no complete skeletons have been recovered from the quarry, but as is often the case with mammoth sites numerous molar teeth and jaws have been found in addition to a few scattered bones from the limbs (see above illustration for a look at some teeth and a jaw). Altogether the bones appear to represent at least four individuals, and the robustness of the jaws and curvature of a tusk suggest that most of these animals were adult males. (As the authors note, however, the bones of females and juveniles may have been found and taken away by quarrymen and collectors. How the site formed, and if there was any bias as to the individuals preserved, is as yet unknown.) When compared to woolly mammoth remains recovered from the North Sea between the UK and the European continent there seemed to be no significant differences between the bones; the animals from Spain were woolly mammoths.
Yet southern Spain in the time of the woolly mammoths was strikingly different from what it is like today. Not only was it colder about 30,000-40,000 years ago, but the landscape was a nearly treeless steppe. The spread of this open, grassland habitat created an edible highway for the woolly mammoths. Despite the fact that living elephants are mixed feeders that are browsers, woolly mammoths were grazers that fueled their large bodies with grass.
But how did the mammoths get there? According to the authors, woolly mammoths migrated into Spain through the region known as the Basque Country along the northern border with modern-day France. The species then expanded to the west and south, although it appears that mountains to the south of the site discussed in the paper prevented them from reaching Spain’s Mediterranean coast.
Once they arrived in southern Spain, though, the mammoths did not stay in the area continuously. They were only vacationing. Their presence at the southern site coincides with a climatic cycle in which the area was cold and dry, suitable conditions for the “mammoth steppe” on which the woolly mammoths depended. This pattern can be seen elsewhere in the world at about the same time. As the grasslands expanded, so did the range of the mammoths, and the rising and falling sea levels opened and closed pathways along the coastlines. Some of these fluctuations even precipitated the evolution of pygmy mammoths in places like the Channel Islands off California, but that is a story for another time.
[H/T to Archy for bringing this story to my attention.]
Álvarez-Lao, D., Kahlke, R., García, N., & Mol, D. (2009). The Padul mammoth finds — On the southernmost record of Mammuthus primigenius in Europe and its southern spread during the Late Pleistocene Palaeogeography, Palaeoclimatology, Palaeoecology, 278 (1-4), 57-70 DOI: 10.1016/j.palaeo.2009.04.011