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The oral microbiome plays key roles in human biology, health, and disease, but little is known about the global diversity, variation, or evolution of this microbial community. To better understand the evolution and changing ecology of the human oral microbiome, we analyzed 124 dental biofilm metagenomes from humans, including Neanderthals and Late Pleistocene to present-day modern humans, chimpanzees, and gorillas, as well as New World howler monkeys for comparison. We find that a core microbiome of primarily biofilm structural taxa has been maintained throughout African hominid evolution, and these microbial groups are also shared with howler monkeys, suggesting that they have been important oral members since before the catarrhine-platyrrhine split ca. 40 Mya. However, community structure and individual microbial phylogenies do not closely reflect host relationships, and the dental biofilms of Homo and chimpanzees are distinguished by major taxonomic and functional differences. Reconstructing oral metagenomes from up to 100 thousand years ago, we show that the microbial profiles of both Neanderthals and modern humans are highly similar, sharing functional adaptations in nutrient metabolism. These include an apparent Homo -specific acquisition of salivary amylase-binding capability by oral streptococci, suggesting microbial coadaptation with host diet. We additionally find evidence of shared genetic diversity in the oral bacteria of Neanderthal and Upper Paleolithic modern humans that is not observed in later modern human populations. Differences in the oral microbiomes of African hominids provide insights into human evolution, the ancestral state of the human microbiome, and a temporal framework for understanding microbial health and disease., Competing Interests: The authors declare no competing interest., (Copyright © 2021 the Author(s). Published by PNAS.)

Although the key role of long-distance trade in the transformation of cuisines worldwide has been well-documented since at least the Roman era, the prehistory of the Eurasian food trade is less visible. In order to shed light on the transformation of Eastern Mediterranean cuisines during the Bronze Age and Early Iron Age, we analyzed microremains and proteins preserved in the dental calculus of individuals who lived during the second millennium BCE in the Southern Levant. Our results provide clear evidence for the consumption of expected staple foods, such as cereals (Triticeae), sesame ( Sesamum ), and dates ( Phoenix ). We additionally report evidence for the consumption of soybean ( Glycine ), probable banana ( Musa ), and turmeric ( Curcuma ), which pushes back the earliest evidence of these foods in the Mediterranean by centuries (turmeric) or even millennia (soybean). We find that, from the early second millennium onwards, at least some people in the Eastern Mediterranean had access to food from distant locations, including South Asia, and such goods were likely consumed as oils, dried fruits, and spices. These insights force us to rethink the complexity and intensity of Indo-Mediterranean trade during the Bronze Age as well as the degree of globalization in early Eastern Mediterranean cuisine., Competing Interests: The authors declare no competing interest.

Flowering plants possess mechanisms that stimulate positive emotional and social responses in humans. It is difficult to establish when people started to use flowers in public and ceremonial events because of the scarcity of relevant evidence in the archaeological record. We report on uniquely preserved 13,700-11,700-y-old grave linings made of flowers, suggesting that such use began much earlier than previously thought. The only potentially older instance is the questionable use of flowers in the Shanidar IV Neanderthal grave. The earliest cemeteries (ca. 15,000-11,500 y ago) in the Levant are known from Natufian sites in northern Israel, where dozens of burials reflect a wide range of inhumation practices. The newly discovered flower linings were found in four Natufian graves at the burial site of Raqefet Cave, Mt. Carmel, Israel. Large identified plant impressions in the graves include stems of sage and other Lamiaceae (Labiatae; mint family) or Scrophulariaceae (figwort family) species; accompanied by a plethora of phytoliths, they provide the earliest direct evidence now known for such preparation and decoration of graves. Some of the plant species attest to spring burials with a strong emphasis on colorful and aromatic flowers. Cave floor chiseling to accommodate the desired grave location and depth is also evident at the site. Thus, grave preparation was a sophisticated planned process, embedded with social and spiritual meanings reflecting a complex preagricultural society undergoing profound changes at the end of the Pleistocene.