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Neanderthal - Homo Neanderthalensis
#31
Neanderthals' main food source was definitely meat
Isotope analyses performed on single amino acids in Neanderthals' collagen samples shed new light on their debated diet

Date: February 19, 2019
Source: Max Planck Institute for Evolutionary Anthropology
Summary:
Researchers describe two late Neanderthals with exceptionally high nitrogen isotope ratios, which would traditionally be interpreted as the signature of freshwater fish consumption. By studying the isotope ratios of single amino acids, they however demonstrated that instead of fish, the adult Neanderthal had a diet relying on large herbivore mammals and that the other Neanderthal was a breastfeeding baby whose mother was also a carnivore.

[Image: 190219111704_1_900x600.jpg]
Tooth of an adult Neanderthal from Les Cottés in France. Her diet consisted mainly of the meat of large herbivore mammals.
Credit: © MPI f. Evolutionary Anthropology/ A. Le Cabec

Neanderthals' diets are highly debated: they are traditionally considered carnivores and hunters of large mammals, but this hypothesis has recently been challenged by numerous pieces of evidence of plant consumption. Ancient diets are often reconstructed using nitrogen isotope ratios, a tracer of the trophic level, the position an organism occupies in a food chain. Neanderthals are apparently occupying a high position in terrestrial food chains, exhibiting slightly higher ratios than carnivores (like hyenas, wolves or foxes) found at the same sites. It has been suggested that these slightly higher values were due to the consumption of mammoth or putrid meat. And we also know some examples of cannibalism for different Neanderthal sites.
Paleolithic modern humans, who arrived in France shortly after the Neanderthals had disappeared, exhibit even higher nitrogen isotope ratios than Neanderthals. This is classically interpreted as the signature of freshwater fish consumption. Fishing is supposed to be a typical modern human activity, but again, a debate exists whether or not Neanderthals were eating aquatic resources. When Klervia Jaouen, a researcher at the Max Planck Institute for Evolutionary Anthropology and first author of the study, and collaborators discovered high nitrogen isotope ratios in the collagen of two Neanderthals falling in the range of modern humans, they wondered whether this could a signature of regular fish consumption.
The Neanderthals come from Les Cottés and Grotte du Renne, in France, two sites where no fish remains have been found. However, the measurements were performed on a tooth root, which recorded the diet between four to eight years of the individual's life, and on a bone of a one-year-old baby. These high nitrogen isotope ratios could also indicate that the Neanderthals were not weaned at this age, contradicting in the case of the Les Cottés Neanderthal (the one whose tooth root was analyzed) former pieces of evidence of early weaning around one year of age. In other words, many explanations (e.g. freshwater fish consumption, putrid meat, late weaning or even cannibalism) could account for such high values, and identifying the factor involved could change our understanding of Neanderthals' lifestyles.

Analysis of amino acids

In order to explain these exceptionally high nitrogen isotope ratios, Jaouen and collaborators decided to use a novel isotope technique. Compound-specific isotope analyses (CSIA) allow to separately analyze the amino acids contained in the collagen. Some of the amino acid isotope compositions are influenced by environmental factors and the isotope ratios of the food eaten. Other amino acid isotope ratios are in addition influenced by the trophic level. The combination of these amino acid isotope ratios allows to decipher the contribution of the environment and the trophic level to the final isotope composition of the collagen.
"Using this technique, we discovered that the Neanderthal of Les Cottés had a purely terrestrial carnivore diet: she was not a late weaned child or a regular fish eater, and her people seem to have mostly hunted reindeers and horses," says Jaouen. "We also confirmed that the Grotte du Renne Neanderthal was a breastfeeding baby whose mother was a meat eater." Interestingly, this conclusion matches with the observations of the zooarcheologists.
The study also illustrates the importance of this new isotope technique for future investigations into ancient human and Neanderthal diets. Using compound-specific isotope analysis allowed the researchers not to misinterpret the global nitrogen isotope ratio which was exceptionally high. Michael P. Richards of the Simon Fraser University in Canada comments: "Previous isotope results indicated a primarily carnivorous diet for Neanderthals, which matches the extensive archaeological record of animal remains found and deposited by Neanderthals. There has recently been some frankly bizarre interpretations of the bulk isotope data ranging from Neanderthals primarily subsisting on aquatic plants to eating each other, both in direct contrast to the archaeological evidence. These new compound-specific isotope measurements confirm earlier interpretations of Neanderthal diets as being composed of mainly large herbivores, although of course they also consumed other foods such as plants."

Monotonous diet

In addition to confirming the Neanderthals as terrestrial carnivores, this work seems to indicate that these hominins had a very monotonous diet over time, even once they had started to change their material industry, possibly under the influence of modern humans. The baby Neanderthal of Grotte du Renne was indeed found associated to the Châtelperronian, a lithic technology similar to that of modern humans. Late Neanderthals were therefore very humanlike, painting caves and wearing necklaces, but unlike their sister species, did not seem to enjoy fishing.
Jean-Jacques Hublin, director of the Department of Human Evolution at the Max Planck Institute for Evolutionary Anthropology, comments: "This study confirms that when Homo sapiens arrived in Europe and met Neanderthals, they were in direct competition for the exploitation of large mammals." "The systematic use of the combination of CSIA and radiocarbon dating will help to understand if the two species really had the same subsistence strategies during those crucial times," concludes Sahra Talamo, a researcher at the Leipzig Max Planck Institute.


Story Source: Max Planck Institute for Evolutionary Anthropology. "Neanderthals' main food source was definitely meat: Isotope analyses performed on single amino acids in Neanderthals' collagen samples shed new light on their debated diet." ScienceDaily. www.sciencedaily.com/releases/2019/02/190219111704.htm (accessed February 19, 2019).



Journal Reference:
  1. Klervia Jaouen, Adeline Le Cabec, Frido Welker, Jean-Jacques Hublin, Marie Soressi, Sahra Talamo. Exceptionally high δ15N values in collagen single amino acids confirm Neandertals as high-trophic level carnivores. PNAS, 2019 DOI: 10.1073/pnas.1814087116
Abstract
Isotope and archeological analyses of Paleolithic food webs have suggested that Neandertal subsistence relied mainly on the consumption of large herbivores. This conclusion was primarily based on elevated nitrogen isotope ratios in Neandertal bone collagen and has been significantly debated. This discussion relies on the observation that similar high nitrogen isotopes values could also be the result of the consumption of mammoths, young animals, putrid meat, cooked food, freshwater fish, carnivores, or mushrooms. Recently, compound-specific C and N isotope analyses of bone collagen amino acids have been demonstrated to add significantly more information about trophic levels and aquatic food consumption. We undertook single amino acid C and N isotope analysis on two Neandertals, which were characterized by exceptionally high N isotope ratios in their bulk bone or tooth collagen. We report here both C and N isotope ratios on single amino acids of collagen samples for these two Neandertals and associated fauna. The samples come from two sites dating to the Middle to Upper Paleolithic transition period (Les Cottés and Grotte du Renne, France). Our results reinforce the interpretation of Neandertal dietary adaptations as successful top-level carnivores, even after the arrival of modern humans in Europe. They also demonstrate that high δ15N values of bone collagen can solely be explained by mammal meat consumption, as supported by archeological and zooarcheological evidence, without necessarily invoking explanations including the processing of food (cooking, fermenting), the consumption of mammoths or young mammals, or additional (freshwater fish, mushrooms) dietary protein sources.

https://www.pnas.org/content/early/2019/...1814087116
[Image: wildcat10-CougarHuntingDeer.jpg]
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#32
Neanderthals walked upright just like the humans of today

Date:  February 25, 2019
Source:  University of Zurich

[Image: 190225170236_1_540x360.jpg]
Virtual reconstruction of the skeleton found in La Chapelle-aux-Saints, based on high-resolution 3D surface scans of the spine and pelvis. Credit: Martin Häusler, UZH

Neanderthals are often depicted as having straight spines and poor posture. However, these prehistoric humans were more similar to us than many assume. University of Zurich researchers have shown that Neanderthals walked upright just like modern humans -- thanks to a virtual reconstruction of the pelvis and spine of a very well-preserved Neanderthal skeleton found in France.
An upright, well-balanced posture is one of the defining features of Homo sapiens. In contrast, the first reconstructions of Neanderthals made in the early 20th century depicted them as only walking partially upright. These reconstructions were based on the largely preserved skeleton of an elderly male Neanderthal unearthed in La Chapelle-aux-Saints, France.

Changing perspectives

Since the 1950s, scientists have known that the image of the Neanderthal as a hunched over caveman is not an accurate one. Their similarities to ourselves -- both in evolutionary and behavioral terms -- have also long been known, but in recent years the pendulum has swung in the opposite direction. "Focusing on the differences is back in fashion," says Martin Haeusler, UZH specialist in evolutionary medicine. For instance, recent studies have used a few isolated vertebrae to conclude that Neanderthals did not yet possess a well-developed double S-shaped spine.
However, a virtual reconstruction of the skeleton from La Chapelle-aux-Saints has now delivered evidence to the contrary. This computer-generated anatomical model was created by the research group led by Martin Haeusler from the University of Zurich and included Erik Trinkaus from Washington University in St. Louis. The researchers were able to show that both the individual in question as well as Neanderthals in general had a curved lumbar region and neck -- just like the humans of today.

Sacrum, vertebrae and signs of wear as evidence


When reconstructing the pelvis, the researchers discovered that the sacrum was positioned in the same way as in modern humans. This led them to conclude that Neanderthals possessed a lumbar region with a well-developed curvature. By putting together the individual lumbar and cervical vertebrae, they were able to discern that the spinal curvature was even more pronounced. The very close contact between the spinous processes -- the bony projections off the back of each vertebra -- became clear, as did the prominent wear marks that were in part caused by the curvature of the spine.

Recognizing similarities


Wear marks in the hip joint of the La Chapelle-aux-Saints skeleton also pointed to the Neanderthals having an upright posture similar to that of modern humans. "The stress on the hip joint and the position of the pelvis is no different than ours," says Haeusler. This finding is also supported by analyses of other Neanderthal skeletons with sufficient remnants of vertebrae and pelvic bones. "On the whole, there is hardly any evidence that would point to Neanderthals having a fundamentally different anatomy," explains Haeusler. "Now is the time to recognize the basic similarities between Neanderthals and modern humans and to switch the focus to the subtle biological and behavioral changes that occurred in humans in the late Pleistocene."


Story Source: University of Zurich. "Neanderthals walked upright just like the humans of today." ScienceDaily. www.sciencedaily.com/releases/2019/02/190225170236.htm (accessed February 25, 2019).



Journal Reference:
  1. Haeusler M, Trinkaus E, Fornai C, Müller J, Bonneau N, Boeni T, Frater NT. Morphology, Pathology and the Vertebral Posture of the La Chapelle-aux-Saints Neandertal.. Proceedings of the National Academy of Sciences, 2019 DOI: 10.1073/pnas.1820745116
Abstract
Although the early postural reconstructions of the Neandertals as incompletely erect were rejected half a century ago, recent studies of Neandertal vertebral remains have inferred a hypolordotic, flat lower back and spinal imbalance for them, including the La Chapelle-aux-Saints 1 skeleton. These studies form part of a persistent trend to view the Neandertals as less “human” than ourselves despite growing evidence for little if any differences in basic functional anatomy and behavioral capabilities. We have therefore reassessed the spinal posture of La Chapelle-aux-Saints 1 using a new pelvic reconstruction to infer lumbar lordosis, interarticulation of lower lumbar (L4-S1) and cervical (C4-T2) vertebrae, and consideration of his widespread age-related osteoarthritis. La Chapelle-aux-Saints 1 exhibits a pelvic incidence (and hence lumbar lordosis) similar to modern humans, articulation of lumbar and cervical vertebrae indicating pronounced lordosis, and Baastrup disease as a product of his advanced age, osteoarthritis, and lordosis. Our findings challenge the view of generally small spinal curvatures in Neandertals. Setting aside the developmentally abnormal Kebara 2 vertebral column, La Chapelle-aux-Saints 1 is joined by other Neandertals with sufficient vertebral remains in providing them with a fully upright (and human) axial posture.

https://www.pnas.org/content/early/2019/...1820745116
[Image: wildcat10-CougarHuntingDeer.jpg]
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  • Claudiu Constantin Nicolaescu
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#33
Is there a way to put/copy sommatively the description of the Neanderthal man in the Ice Age discoveries thread ! That would helps a lot for analysis of interactions between ice age animals !?

Thanks !
Just a normal guy who want to learn things !
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