Neolithic dental calculi provide evidence for environmental proxies and consumption of wild edible fruits and herbs in central Apennines

Abstract

Looking for a biological fingerprint relative to new aspects of the relationship between humans and natural environment during prehistoric times is challenging. Although many issues still need to be addressed in terms of authentication and identification, microparticles hidden in ancient dental calculus can provide interesting information for bridging this gap of knowledge. Here, we show evidence about the role of edible plants for the early Neolithic individuals in the central Apennines of the Italian peninsula and relative cultural landscape. Dental calculi from human and animal specimens exhumed at Grotta Mora Cavorso (Lazio), one of the largest prehistoric burial deposits, have returned an archaeobotanical record made up of several types of palaeoecological proxies. The organic fraction of this matrix was investigated by a multidisciplinary approach, whose novelty consisted in the application of next generation sequencing to ancient plant DNA fragments, specifically codifying for maturase K barcode gene. Panicoideae and Triticeae starches, together with genetic indicators of Rosaceae fruits, figs, and Lamiaceae herbs, suggested subsistence practices most likely still based on wild plant resources. On the other hand, pollen, and non-pollen palynomorphs allowed us to outline a general vegetational framework dominated by woodland patches alternated with meadows, where semi-permanent settlements could have been established.

Microparticles from dental calculus disclose paleoenvironmental and palaeoecological records

“…The failure to find legume starches in the investigated dental calculi seems to be in line with the evidence obtained from other studies on ancient tartar of prehistorical periods (Carra et al., 2022; D'Agostino, Di Marco, Marvelli, Marchesini, Rizzoli, et al., 2022; Lippi et al., 2017; Nava et al., 2021; Oxilia et al., 2021) and the scarce record of pulses registered in Italian Neolithic archaeological sites (Bouby et al., 2020; Celant, 2020), although Fabaceae are among the most adaptable plants to a wide range of habitats and dry legume seeds are capable of being well stored. However, pulses could have been less appreciated by the Neolithic people as a crop because of their low yield, compared to cereals and due to their content in a wide range of potentially toxic metabolites (e.g., saponins, alkaloids).…”

“…In the current work, the analysis of starch granules retrieved from La Sassa samples showed the use of caryopses belonging to C 4 plants in individuals dated to CA, EBA and MBA1/2. These data are not unexpected, as starches of similar morphology have already been found in Neolithic dental calculus from Grotta Continenza (Abruzzi; Nava et al., 2021) and Mora Cavorso (Lazio; D'Agostino, Di Marco, Marvelli, Marchesini, Rizzoli, et al., 2022) and CA‐BA samples from Grotta dello Scoglietto (Tuscany; Lippi et al., 2017) and Casale del Dolce (Lazio; D'Agostino et al., 2021), representing further proof of an already established presence of C 4 plants in the human diet. Therefore, our data from La Sassa confirm the processing of Panicoideae in southern Lazio, already documented by D'Agostino et al.…”

“…In support of this practice, the discovery of Ficus sp. and Rosaceae ancient DNA in Neolithic dental calculi from Mora Cavorso (Lazio, Central Italy) can be mentioned (D'Agostino, Di Marco, Marvelli, Marchesini, Rizzoli, et al., 2022), together with the finding of carpological records of Corylus avellana L., Cornus mas L., Crataegus sp., Malus sylvestris Mill., Pyrus sp., Prunus sp., Quercus sp. L and Vitis vinifera ssp.…”

“…(2023), no isotopic value for C 4 plants in Italian prehistory is available; thus, they have not had the possibility to check whether the recorded value for that single individual was derived reliably from an exclusive consumption of those species. Studies on dental calculus, instead, have testified knowledge of panicoids since the Late Palaeolithic in Southern Italy and Sicily (Carra et al., 2022), the Upper Palaeolithic in Abruzzi (Nava et al., 2021) and the Neolithic‐Bronze Age in Tuscany and Lazio (D'Agostino et al., 2021; D'Agostino, Di Marco, Marvelli, Marchesini, Rizzoli, et al., 2022; Lippi et al., 2017), even if the employment was a rare occasion of use. Evidence of grasses belonging to the Panicoideae subfamily was found in our samples, confirming their use and suggesting ecological aspects of the places frequented by the individuals.…”

“…Taking into consideration the work of Farrer et al. (2021) and our previous evidence (D'Agostino, Di Marco, Marvelli, Marchesini, Rizzoli, et al., 2022), tartar was treated with ultraviolet radiation (UV) for 10 min and immersed in 5% sodium hypochlorite (NaClO), to minimise the exogenous content of the outer surface of the ancient calculus flakes. Afterward, samples were washed twice with ultrapure sterilised water and dried out at 37°C.…”