En règle générale, les animaux sauvages sont moins gras que les animaux d’élevage (même s’il ne faut pas sous-estimer le contenu total en lipides des animaux sauvages). Il semble évident d’en conclure que l’alimentation des chasseurs-cueilleurs comprend moins de lipides que l’alimentation des pays industrialisés. Ce n’est peut-être pas si simple. Les lipides sont une part essentielle de la nutrition humaine, per se, mais aussi par leur contenu en micro-nutriments. Les chasseurs-cueilleurs ont donc tendance à adopter des stratégies afin de maximiser leur apport en lipides :
– Préférence pour les espèces les plus grasses.
– Changement d’espèces cibles en fonction de la saison.
– Ciblage des animaux les plus gras (femelles, jeunes…)
– Ciblage des parties grasses de l’animal, et éventuellement rejet de certaines parties maigres.
L’accès aux lipides des chasseurs-cueilleurs est donc possiblement beaucoup plus important que ce que pourrait laisser penser la simple dichotomie animaux sauvages maigres vs animaux d’élevage gras. A l’inverse, nous avons souvent tendance dans nos sociétés à rejeter certaines parties grasses des animaux, et à nous focaliser sur les parties les plus maigres, telles que le muscle (qui est bien entendu plus gras que le muscle des animaux sauvages, mais plus maigre que des parties souvent délaissées dans nos sociétés comme la moelle osseuse, la graisse sous-cutanée, ou la graisse intra-osseuse).
Les espèces sauvages ne sont pas si maigres qu’on le pense. Globalement, la valeur calorique des lipides y est assez proche de celle des protéines, et peut-être supérieure chez les grands animaux. Ben-Dor & Barkai donnent ici, d’après Ledger, 1968, des valeurs entre 25 et 50% pour les animaux jusqu’à 200kg, et entre 45 et 70% pour les animaux au-delà de 200kg.
Prey Size Decline as a Unifying Ecological Selecting Agent in
Pleistocene Human Evolution [PDF]
Ben-Dor & Barkai
Journal of anthropological archeology, 2021
Ici, Pontzer & Wood proposent des valeurs très proches pour les lipides, comprises entre 33% pour les plus petits animaux et 46% pour les animaux de 200kg. Ils ne donnent malheureusement pas de valeurs pour les animaux plus gros.
Effects of Evolution, Ecology, and Economy on Human Diet: Insights from Hunter-Gatherers and Other Small-Scale Societies [Sup. Material]
Pontzer & Wood
Annual review of nutrition, 2021
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Il est possible aux humains de choisir de cibler les espèces les plus grasses, et de choisir au sein de l’animal les portions les plus grasses.
Excess protein enabled dog domestication during severe Ice Age winters [Texte]
Lahtinen et al.
Nature, 2021
Modern human populations have means to avoid excessive amounts of animal protein in their diet by shifting their exploitation strategies toward fauna retaining higher levels of fat deposits such as fish and bear and avoiding lean meat21.
[…] Hunter-gatherers can avoid lean meat by modifying how they butcher ungulates in order to focus on body elements from which fat and grease can be extracted. Distal limbs and crania maintain fat deposits27. Limb bones can be used to extract fatty oils, and there is evidence for such processing behavior during the Upper Palaeolithic
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Il est possible que nos ancêtres aient changé de cible alimentaire selon la saison, pour viser des proies plus grasses quand le taux de lipides de leurs proies de prédilection baisse.
What where they up against? Lower paleolithic hominin meat acquisition and competition with plio-pleistocene carnivores [PDF]
Starkovich & Conard
In Human behavioural adaptations to interglacial lakeshore environments, 2020
The authors argue that at certain times of year, these taxa become sessile prey that are easily collected without any specialized hunting technologies. Specifically, catfish spawn in shallow pools during the dry season, and are vulnerable to becoming stranded. Because they have primitive lungs, they can live out of water for multiple days, providing an easily collected fresh aquatic food source for homi-
nins and other animals (Stewart 2010; Archer et al. 2014). Access to this type of prey is important for two reasons. First, catfish are available in the late dry season, when ungulate fat stores are depleted. Second, aquatic resources provide docosahexaenoic
acid and long-chain polyunsaturated fatty acids that are linked to brain growth in hominins.
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Les humains semblent s’être adaptés à une alimentation plus grasse que celle des chimpanzés (par ailleurs, ils sont adaptés à une alimentation plus riche en amidon).
Comparative analyses of chromatin landscape in white adipose tissue suggest humans may have less beigeing potential than other primates [PDF]
Smain-Lenz et al.
Genome biology and evolution, 2019
Taken together, these results suggest that humans shut down regions of the genome to accommodate a high fat diet while chimpanzees open regions of the genome to accommodate a high sugar diet.
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Use of Animal Fat as a Symbol of Health in Traditional societies Suggests Humans may be Well Adapted to its Consumption [PDF]
Miki Ben-Dor
Journal of evolution and health, 2015
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L’élephant semble avoir été une proie très prisée, quand les humains ont eu la capacité de les chasser. Il semble qu’ils aient visé préférentiellement les juvéniles, au profil nutritionnel plus intéressant.
A taste of an elephant: The probable role of elephant meat in Paleolithic diet preferences [PDF]
Hagar Reshef & Ran Barkai
Quaternary International, 2015
We suggest that early hominins might have had taste preferences and that elephant meat played a significant role in their diet, when available. Furthermore, the archaeological evidence coupled with ethnographic observations and the study of frozen mammoths suggest that juvenile elephants were specifically a delicacy and were hunted intentionally since their specific meat and fat composition seems to have had a better taste and a better nutritional value.
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Man the fat hunter: the demise of Homo erectus and the emergence of a new hominin lineage in the Middle Pleistocene (ca. 400 kyr) Levant [Texte]
Ben-Dor et al.
PlosOne, 2011
We employ a bio-energetic model to present a hypothesis that the disappearance of the elephants, which created a need to hunt an increased number of smaller and faster animals while maintaining an adequate fat content in the diet, was the evolutionary drive behind the emergence of the lighter, more agile, and cognitively capable hominins.
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Mais il faut aussi lire Speth en 2019, article portant principalement sur néandertal, mais probablement valable pour Sapiens [Texte] :
Thus, while wolves, hyenas, and felines can thrive on a diet in which protein provides as much as 70% of total energy (Schermerhorn, 2013:2), northern latitude hunter-gatherers (and presumably Paleolithic foragers as well) would experience dire health consequences, and even death, within a matter of weeks if their protein intake regularly exceeded roughly half that amount (i.e., ca. 35% of total kcal) (Cordain et al., 2000; Speth, 2010). In other words, fat is far more important to the survival of meat-dependent humans (including Neanderthals) than it is to hypercarnivores.
This difference may help explain why Neanderthals, and later humans, routinely targeted prime adults, the age cohort with the highest overall fat levels, while hypercarnivores could make do with fat-poor juveniles and fat-depleted old adults (their capture of course also posed less risk of injury and failure). This important contrast is easily missed in dietary reconstructions based on δ15N values. Neanderthal hunters would have had to exercise far greater selectivity than hypercarnivores with regard to the species, age, sex, reproductive state, and overall condition of the animals they targeted and the body parts they processed and consumed (contra White et al., 2016). At times and in contexts where plant foods were scarce or unavailable, hunting wasn’t just a matter of opportunistically killing an animal and bringing home the meat. To survive the coldest months of the year, hunters had to provide fat in substantial quantities on a regular basis—in fact, as much as 60% or more of total calories (Cordain et al., 2000; Speth, 2010).
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Au Paléolithique déjà… « Le gras, c’est la vie ! » [Texte] [Texte]
Daujeard & Vettese
The Conversation, 2022
Pourquoi le gras a-t-il été si important pour les sociétés du Paléolithique, période gigantesque s’étirant de 3 millions à 12 000 ans avant le présent, toutes latitudes confondues ? Comment les vestiges fossiles nous renseignent sur cette récupération de la graisse, tant par Homo sapiens que Néandertal ? Et en quoi certaines préparations culinaires observées dans les sociétés traditionnelles actuelles nous aident à émettre des hypothèses et à mieux comprendre les « cuisines » paléolithiques ?
Anthropogoniques 