• A glimpse into Neanderthal life

     

    A fascinating study from Naturwissenschaften (Ha. Spellcheck’s going crazy.) telling us researchers have found evidence that neanderthals may have used some medicinal plants, cooked some of their food and ate far more plant material than previously thought.

         Neanderthals disappeared sometime between 30,000 and 24,000 years ago. Until recently, Neanderthals were understood to have been predominantly meat-eaters; however, a growing body of evidence suggests their diet also included plants. We present the results of a study, in which sequential thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) were combined with morphological analysis of plant microfossils, to identify material entrapped in dental calculus from five Neanderthal individuals from the north Spanish site of El Sidrón. Our results provide the first molecular evidence for inhalation of wood-fire smoke and bitumen or oil shale and ingestion of a range of cooked plant foods. We also offer the first evidence for the use of medicinal plants by a Neanderthal individual. The varied use of plants that we have identified suggests that the Neanderthal occupants of El Sidrón had a sophisticated knowledge of their natural surroundings which included the ability to select and use certain plants.

    Fascinating.

         Although a buccal molar microwear study has suggested a largely carnivorous diet for the Neanderthals of Gorham’s Cave (Lalueza and Pérez-Pérez 1993), a broader survey argues for a mixed diet of animals and plants, with a possible focus on more fibrous plants such as roots and bulbs in cooler periods (Pérez-Pérez et al. 2003). A comparison of occlusal molar microwear patterns including one sample from El Sidrón (SDR-005) suggests a higher consumption of plants in more wooded environments (El Zaatari et al. 2011).
         From a broader evolutionary perspective, human saliva contains a substantially higher number of AMY1 copy variants of the enzyme α-amylase than most other higher primates. The primary role of α-amylase is to break down starch molecules into accessible sugars. As the main constituent of cereal grains, plant storage roots and tubers, many nuts and some inner bark, starch offers the most direct dietary source of glucose, the essential provider of metabolic energy. It has been suggested that the increase in AMY1 copy variants may have developed as a result of a dietary shift to starchy tubers by early hominins (Perry et al. 2007).

    It’s amazing to me that scientists can discover so much from tooth calculus. Simply amazing. What I found interesting, however, is the prevalence of tubers in the neanderthal diet:

         The principal problem in evaluating the exploitation of plants in pre-agricultural times is the lack of direct evidence; nonetheless, O’Connell et al. (1999) argue that Homo erectus had a high dependence on tubers. It has also been argued that the exploitation of starchy roots was a significant factor in the expansion of hominins into a savannah environment (Laden and Wrangham 2005). Although these are theoretical perspectives, they correlate well with the high salivary amylase identified in modern humans in comparison with other higher primates (Perry et al. 2007).
         The presence of pigments and bitter-tasting appetite suppressants (dihydroazulene and chamazulene, and the coumarin, 4-methylherniarin) in the calculus of Young Adult 4—SD1604 is intriguing. One possible reason for the consumption of bitter-tasting plants with no nutritional value and containing these compounds (such as yarrow and camomile) would be for self-medication. All the higher primates have a wide and applied knowledge of the edible plants within their environments, and there is an extensive body of evidence demonstrating the complex use of medicinal plants for zoopharmacognosy by animals including all modern higher primates (e.g., Rodriguez and Wrangham 1993; Cousins and Huffman 2002; Huffman 1997, 2003; Singer et al. 2009; Lisonbee et al. 2003; Krief et al. 2005; Huffman and Vitazkova 2007).
         The starch granules and carbohydrate markers in these samples, the evidence for the azulene and coumarin compounds, the possible evidence for nuts, grasses, and possibly even green vegetables, argue for a broader use of ingested plants than is often suggested by stable isotope analysis. This view is compounded by the surprisingly low levels of protein markers (in the form of diketopiperazines, DKPs), which were lower than in control samples of modern calculus from dog and sheep (ESM_1.pdf). Though preferential degradation of residual protein was considered, the survival of sufficient levels of collagen in both bones and teeth to undertake racemization and radiocarbon dating (de Torres et al. 2010) suggests that the absence of protein is a genuine indicator of low protein levels in the diet during the period over which the dental calculus accumulated.
         The beginnings of cooking are suggested to be as far back as 1.9 Ma (Wrangham et al. 1999); the presence of hearths and burnt bone on many Neanderthal sites suggests that they cooked at least some of their food. Using mass spectrometry, we have identified the ingestion of cooked carbohydrates in the calculus of two adults, one adult in particular having apparently eaten several different carbohydrate-rich foods. The evidence for cooked carbohydrates is confirmed both by the cracked/roasted starch granules observed microscopically and the molecular evidence for cooking and exposure to wood smoke or smoked food in the form of methyl esters, phenols, and polynuclear aromatic hydrocarbons (notably pyrene and fluoranthene) found in the dental calculus.
         Neanderthals lived through different climatic regimes, including periods in which numerous edible plants were available for exploitation (Jones 2009; Hardy 2010; El Zaatari et al. 2011). We propose that that the Neanderthal occupants of El Sidrón, whose hypothesized, cannibalized remains (Rosas et al. 2006) were discarded at the site, had a sophisticated knowledge of their natural surroundings, and were able to recognize both the nutritional and the medicinal value of certain plants. Although the extent of their botanical knowledge and their ability to self-medicate must of course remain open to speculation, the fact that higher primates have some understanding of the flora within their environment, and the extensive evidence for self-medication within the animal kingdom, would surely make it surprising if the Neanderthals did not also share such knowledge.
         We believe that our findings offer the first direct molecular evidence for the ingestion of carbonized food and the inhalation of smoke by a Neanderthal individual. We also offer the first measurable molecular evidence that dental calculus is a trap for ingested material, the starch granules reported from El Sidrón representing the oldest granules ever to be confirmed using a biochemical test. Our approach to the study of this material, combining analytical chemistry with morphological observation, offers the opportunity to maximize the biographical detail to be gained for ancient human populations.

    That’s it. I’m whipping up a tater for lunch.

    Fascinating link.

    Category: Science

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    Article by: Beth Erickson

    I'm Beth Ann Erickson, a freelance writer, publisher, and skeptic. I live in Central Minnesota with my husband, son, and two rescue pups. Life is flippin' good. :)