Diets a topic of debate; Researchers look into zinc isotopes in molar sample
New research suggests that the closest extinct relatives of humans, the Neanderthals, may have been carnivores. The diets of Homo neanderthalensis have been a topic of debate for a long time.
Neanderthals showed high levels of carnivory, lending more weight to the theory suggesting that our extinct relatives may have been primarily meat eaters, according to a new study.
Researchers in the new study examined a molar belonging to a Neanderthal individual found in Iberia using a less explored technique. The individual was found at the Gabasa site in Spain.
Analysis showed that the individual did not consume the blood of their prey, the study published in journal Proceedings of the National Academy of Sciences highlighted. However, the individual ate the bone marrow of their prey.
Some previous studies examining the dental tartar of remains from the Iberian Peninsula show that Neanderthals were majorly herbivores.
Other studies conducted outside the Iberian Peninsula, according to the researchers, indicate that our extinct relatives feasted on a meat-heavy diet.
Another study recorded evidence of cannibalism at two Iberian sites. But this may be due to nutritional stress.
"I wanted to see how different their diets were from those of modern humans and how to explain it," Klevia Jaouen, the lead author from the French National Centre for Scientific Research (CNRS), told Down To Earth.
This is important because the disappearance of this species is frequently attributed to their subsistence strategy or how they sourced food and other raw materials from their environment.
Previous techniques analysed nitrogen isotopes in the bone collagen. However, this method is suitable in temperate environments, the experts stated. They are less likely to work on samples over 50,000 years old as collagen degrades over time depending on the environmental conditions, the paper said.
But the Gabasa site in Spain could not meet the required conditions. So Jaouen and her colleagues decided to use zinc isotopes in the molar sample. Their analysis showed that this individual switched to an adult diet from the mother’s milk before age two.
The Neandertal individual from Gabasa, according to the study, showed a zinc isotope signature of a top-level carnivore.
The researchers ruled out cannibalism due to the absence of cut marks on hominin (a group consisting of modern humans, extinct human species and all our immediate ancestors) and carnivore bones.
A low zinc value suggests that the species ate muscle and liver from deer and rabbits, leaving out their blood and bones.
Other carnivores like red foxes, wolves and lynxes have been known to gnaw or partially digest bones. They also consume blood, said the study. These trends suggest that the Gabasa individual might have been on a diet distinct from other carnivores, the researchers wrote in the study.
Jaouen could not document any plant consumption based on the zinc-isotope analysis. “But if they ate fruits from time to time, we could not detect it because fruits do not contain a lot of zinc,” the expert explained.
Plant consumption was probably not a substantial part of their diets, she added. The researchers are also unsure whether Neanderthals showed regional differences in food consumption.
“We would like to confirm these conclusions by analysing more specimens. We are working on it,” she said.
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.