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Marciani, G.

Publications and source records attributed to Marciani, G..

3 recordsLinked to original sources

A multidisciplinary investigation into whether Andean caravans reached the southern lowlands of the Parana-Plata basin during pre-Columbian times

The expansion of llama caravans and the dispersal of domesticated camelids to extra-Andean regions is one of the key topics in South American archaeology, as it reflects the degree of connection between Andean societies and the surrounding lowland societies, as well as the extent of pre-Columbian pastoralism. One of the primary indicators of both processes is the presence of domesticated camelids in the archaeological record, particularly the llama (Lama glama). Based on somewhat ambiguous historical evidence, it has been suggested that llama caravanning may have reached the northern Pampean region and the southern Parana River valley from an unspecified time until historical times. While the archaeological sites in these two regions have abundant camelid remains that have thus far been identified as guanaco (Lama guanicoe), the possibility of misidentification due to the osteometric similarity between the domestic and wild camelids could mask the presence of llamas in the record, undermining evidence of this potential major expansion of llama caravans. To clarify this issue, we applied a multidisciplinary approach combining archaeological, isotopic, and paleogenomic analyses to determine the taxonomic status of camelids recovered from archaeological sites in both areas. Our findings demonstrate that all the individuals analyzed correspond to guanacos, whose survival extended into early historical times. There is no regional evidence to support the presence of llama caravanning or domesticated camelids in the northern Pampean region or the lower Parana River valley.

genomics↗

Genetics and material culture support repeated expansions into Paleolithic Eurasia from a population hub out of Africa

The population dynamics that followed the out of Africa expansion (OoA) and the whereabouts of the early migrants before the differentiation that ultimately led to the formation of Oceanian, West and East Eurasian macro populations have long been debated. Shedding light on these events may, in turn, provide clues to better understand cultural evolution in Eurasia between 50kya and 35kya. Here we analyze Eurasian Paleolithic DNA evidence to provide a comprehensive population model and validate it in light of available material culture. Leveraging on our integrated approach we propose the existence of a Eurasian population Hub, where Homo sapiens lived between the OoA and the broader colonization of Eurasia, which was characterized by multiple events of expansion and local extinction. A major population wave out of Hub, of which UstIshim, Bacho Kiro and Tianyuan are unadmixed representatives, is broadly associated with Initial Upper Paleolithic lithics and populated West and East Eurasia before or around 45 kya, before getting largely extinct in Europe. In this light, we suggest a parsimonious placement of Oase1 as an individual related to Bacho Kiro who experienced additional Neanderthal introgression. Another expansion, started before 38 kya, is broadly associated with Upper Paleolithic industries and repopulated Europe with sporadic admixtures with the previous wave (GoyetQ116-1) and more systematic ones while moving through Siberia (Yana, Malta).

evolutionary biology↗

Early Alpine human occupation backdates westward human migration in Late Glacial Europe

The end of the Last Glacial Maximum (LGM) in Europe (~16.5 ka ago) set in motion major changes in human culture and population structure1. In Southern Europe, Early Epigravettian material culture was replaced by Late Epigravettian art and technology about 18-17 ka ago at the beginning of southern Alpine deglaciation, although available genetic evidence from individuals who lived ~14 ka ago2-5 opened up questions on the impact of migrations on this cultural transition only after that date. Here we generate new genomic data from a human mandible uncovered at the Late Epigravettian site of Riparo Tagliente (Veneto, Italy), that we directly dated to 16,980-16,510 cal BP (2{sigma}). This individual, affected by a low-prevalence dental pathology named focal osseous dysplasia, attests that the very emergence of Late Epigravettian material culture in Italy was already associated with migration and genetic replacement of the Gravettian-related ancestry. In doing so, we push back by at least 3,000 years the date of the diffusion in Southern Europe of a genetic component linked to Balkan/Anatolian refugia, previously believed to have spread during the later Bolling/Allerod warming event (~14 ka ago4,6). Our results suggest that demic diffusion from a genetically diverse population may have substantially contributed to cultural changes in LGM and post-LGM Southern Europe, independently from abrupt shifts to warmer and more favourable conditions.

genomics↗