The behavior of mountain Neanderthals is still largely unknown to the scientific community, at least within European limits. Different studies have shown thatthe species used animal bones as fuel for bonfiresthat they lit, especially, when the arboreal mass was scarce.
A community of Neanderthals resided in the cave of El Esquilleu (Cantabria), between 53,000 and 30,000 years ago. However, although they had numerous vegetation around them, scientists from the UNED and the Complutense University of Madrid have discovered fossil remains of animals in what could be a bonfire in the cave.
One of the hypotheses raised in their study, published in the journalQuaternary Sciencie Reviews, is that it wasa systematic way of keeping the cave clean, removing any type of residue. “The life of human groups in caves with a lot of humidity, with lurking predators and with decomposing food residues nearby, carried certain risks for these humans who, in addition, had to remain somewhat crowded to cope with the cold”, points out Paloma Uzquiano, a researcher at the UNED and one of the authors of the work. “It is not absurd to think that by systematically eliminating organic waste they will try to avoid greater evils,” he adds. However, the researchers also do not rule out the hypothesis that the bones served, in turn, as fuel for the bonfires.
TheNeanderthals kept those fires lit permanently for both cooking and lighting the cave, build tools and even to avoid mosquito pests, typical in humid environments. “Burning animal waste was a good fuel source for domestic fires, thus saving time and effort,” says Uzquiano.
To see if these bones could serve as fuel, the researchers simulated a total of ten fires, adding different goat bones, the animal to which the remains found at El Esquilleu belonged. These skeletal remains are unusual since, in other Neanderthal bonfires, scientists had found remains of larger animals, such as cows or horses, that had more fat to burn. Another novelty has been to include, along with the trabecular bones –those of the extremities–, axial bones –of the central part of the body–, which are not usually used in these experiments.
“The fires showed thatthe bones of small animals also have combustible qualities and that, in the case of axial bones and epiphyses – ends of a long bone – the combustion process lasted longer”, Details José Yravedra, researcher at the Complutense University of Madrid and co-author of the work.
Resistance to cold and heat
The community of Neanderthals that lived in the cave of El Esquilleu between 53,000 and 30,000 years ago, in the Middle Pleniglacial, had to facestrong stages of atmospheric instability, living both periods of cold and warmer climates.
The dominant vegetation of the Cantabrian area was open and pre-forest in nature, so only scrublands such as legumes, deciduous hawthorn communities, pine, birch, willow, mostard, rowan and juniper ( to a lesser extent) adapted to these changing environments. They also managed to resist oak and hazelnut trees, but sheltered in small enclaves.
For its part, the herbivore fauna that lived among this vegetation was very diverse, with horses, bison and aurochs in open areas; roe deer and wild boar in more wooded environments; goats in the steep areas of the slopes and deer that made movements from the mountains to the valleys.
“This biodiversity made it possible for the groups to settle in an itinerant way in different enclaves, following the seasonal movements of the herds of herbivores, as well as the cycles of the plants throughout that environment,” concludes Uzquiano.
