Researchers used organic compounds embedded in 50,000-year-old dental plaque to study the Neanderthal diet. The plaque contained a range of carbohydrates and starch granules, hinting that the Neanderthals had consumed a variety of plant species. By contrast, there were few lipids or proteins from meat.
They also found, lurking in the plaque of a few specimens, a range of alkyl phenols, aromatic hydrocarbons and roasted starch granules that suggested that the Neanderthals had spent time in smoky areas and eaten cooked vegetables (Abstract).
Among the compounds found were chemicals from plants such as yarrow and camomile, which taste bitter and have no nutritional value. So why they would intentionally eat them? The researchers think they may have been using them medicinally — the plants are used by modern herbalists as anti-inflamatories and antiseptics."
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