Neanderthals, the closest extinct relatives of modern humans, consumed meat, a new study has found. However, these distant cousins of humans did not consume the blood of their prey. The study, led by a researcher from CNRS (French National Centre for Scientific Research), was published October 17 in the journal Proceedings of the National Academy of Sciences (PNAS). The research marks the first time zinc isotope analysis has been used to determine the position of Neanderthals in the food chain. The authors analysed a first molar of a Neanderthal as part of the study. 


Neanderthals, the closest extinct human relative, had defining features such as a huge nose, angled cheek bones, sloped forehead, bodies shorter and bulkier than humans, and large brains. The Neanderthal brain was often larger than the human brain, and was proportional to the brawnier bodies of the extinct hominins. 


Why were scientists not sure of the diet Neanderthals consumed?


Previously, scientists had not settled the question of whether Neanderthals were carnivores or herbivores. Some studies of the dental tartar of individuals from the Iberian Peninsula showed that Neanderthals were major consumers of plants. Meanwhile, other research carried out at sites outside Iberia suggested that. Neanderthals consumed almost nothing but meat. 


Now, researchers have used new analytical techniques on a molar belonging to a Neanderthal, and showed that the Neanderthals at the Gabasa site in Spain appear to have been carnivores. 


 



A first molar belonging to a Neanderthal | Photo: Lourdes Montes/CNRS


Until now, scientists have generally had to extract proteins and analyse the nitrogen isotopes present in the bone collagen, to determine an individual's position in the food chain. However, a drawback of this method is that it can only mostly be used in temperate environments, and only rare on samples more than 50,000 years old. Nitrogen isotope analysis is very complex, or even impossible, when these conditions are not met. The conditions were not met for the molar from the Gabasa site analysed in the new study. 


How does zinc isotope analysis determine if one was a carnivore?


Klevia Jaouen, a CNRS researcher, along with her colleagues, analysed the zinc isotope ratios present in the tooth enamel. This is a mineral resistant to all forms of degradation. The research marked the first time the method of zinc isotope analysis was used to attempt to identify a Neanderthal's diet. According to the study, the lower the proportion of zinc isotopes in the bones, the more likely they are to belong to a carnivore. The researchers also carried out the analysis on the bones of animals from the same time period and geographical area, including carnivores such as lynxes and wolves, and herbivores like rabbits and chamois. The study found that the Neanderthal to whom this tooth from the Gabasa site belonged was probably a carnivore who did not consume the blood of their prey. 


Neanderthals did not consume bones of their prey


The researchers also found broken bones at the site. Together with isotopic data, these bones indicate that the individual also ate the bone of their prey, without consuming the bones. Other chemical traders show that the Neanderthal was accustomed to a carnivorous diet before the age of two. The Neanderthal probably died in the same place they lived in as a child, the study found.


The new zinc isotope analysis method makes it easier to distinguish between omnivores and carnivores, compared to previous techniques. The scientists aim to repeat the experiment on individuals from other sites, including the Payre site in southeast France, to confirm their conclusions.


Modern humans and Neanderthals started coexisting 42,000 years ago


Modern humans and Neanderthals may have coexisted for up to three millennia, in what is now France and Northern Spain, a new study reports. This was until the Neanderthals mysteriously disappeared from Earth around 40,000 years ago. Archaeologists from Leiden University and Cambridge University provide important insights into human evolutionary history in the new study published in Scientific Reports


However, it is still not clear when and where these populations may have existed in Europe, according to the researchers. Neanderthals and modern humans coexisted about 42,000 years ago, when modern humans are believed to have appeared in the region. The overlap existed until about 40,000 years ago, when the Neanderthals mysteriously disappeared from Earth, and became extinct. 


ALSO READ | Modern Humans And Neanderthals May Have Coexisted For Up To Three Millennia, New Study Says


The 2022 Nobel Prize in Physiology was awarded for research on Neanderthals and Denisovans


Swedish geneticist Svante Pääbo, who won the 2022 Nobel Prize in Physiology or Medicine, did pioneering work in the genetic analysis of Neanderthals and Denisovans, the extinct relatives of human beings. Pääbo was awarded the Nobel Prize “for his discoveries concerning the genome of extinct hominins and human evolution". 


Following the migration of Homo sapiens out of Africa around 70,000 years ago, gene transfer occurred from the now extinct hominins to modern humans. The immune system of human beings is able to fight certain infections due to the presence of genes from Neanderthals and Denisovans. 


Pääbo achieved a seemingly impossible task of sequencing the Neanderthal genome. 


Comparative analyses between Neanderthals and Homo sapiens showed that the most recent common ancestor of the two species roamed Earth around 800,000 years ago. 


Through comparative analyses, Pääbo and his team investigated the relationship between Neanderthals and modern-day humans, and found that the DNA sequences were more similar to sequences from contemporary humans originating from Europe or Asia than to contemporary humans originating from Africa. This suggests that Neanderthals and Homo sapiens interbred during their period of coexistence, which lasted thousands of years. 


Approximately one to four per cent of the genome of modern-day humans with European or Asian descent has originated from the Neanderthals. 


There are several Neanderthal genes which affect humans' immune response to different types of infections.


ALSO READ | Nobel Prize 2022: Relationship Between Humans And Extinct Relatives – Discoveries That Won Swedish Geneticist Physiology Nobel


While Neanderthals developed outside Africa and populated Europe and Western Asia from around 400,000 years until 40,000 years ago, Homo sapiens first appeared in Africa approximately 300,000 years ago. Neanderthals mysteriously disappeared from Earth around 40,000 years ago. 


Some groups of Homo sapiens migrated from Africa to the Middle East about 70,000 years ago. From Africa, these groups spread to the rest of the world. Therefore, for tens of thousands of years, Homo sapiens and Neanderthals coexisted in large parts of Eurasia.


While Neanderthals developed outside Africa and populated Europe and Western Asia from around 400,000 years until 40,000 years ago, Homo sapiens first appeared in Africa approximately 300,000 years ago. Neanderthals mysteriously disappeared from Earth around 40,000 years ago. 


Some groups of Homo sapiens migrated from Africa to the Middle East about 70,000 years ago. From Africa, these groups spread to the rest of the world. Therefore, for tens of thousands of years, Homo sapiens and Neanderthals coexisted in large parts of Eurasia.


ALSO READ | Why Did Neanderthals Mysteriously Disappear From Earth 40,000 Years Ago? Researchers Find Clues