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Biology subjects

Rifkin, R. F.

Publications and source records attributed to Rifkin, R. F..

2 recordsLinked to original sources

Ancient DNA of Rickettsia felis and Toxoplasma gondii implicated in the death of a hunter-gatherer boy from South Africa, 2,000 years ago

The Stone Age record of South Africa provides some of the earliest evidence for the biological and cultural origins of Homo sapiens. While there is extensive genomic evidence for the selection of polymorphisms in response to pathogen-pressure in sub-Saharan Africa, there is insufficient evidence for ancient human-pathogen interactions in the region. Here, we analysed shotgun metagenome libraries derived from the sequencing of a Later Stone Age hunter-gatherer child who lived near Ballito Bay, South Africa, c. 2,000 years ago. This resulted in the identification of DNA sequence reads homologous to Rickettsia felis, and the reconstruction of an ancient R. felis genome, the causative agent of typhus-like flea-borne rickettsioses. The concurrent detection of DNA reads derived from Toxoplasma gondii, the causative agent of toxoplasmosis, confirms the pre-Neolithic incidence of these pathogens in southern Africa. We demonstrate that an R. felis and T. gondii co-infection, exacerbated by various additional bacterial and parasitic pathogens, contributed to the ill-health and subsequent demise of the boy from Ballito Bay.

molecular biology↗

Multi-proxy analyses of a mid-15th century Middle Iron Age Bantu-speaker palaeo-faecal specimen elucidates the configuration of the ancestral sub-Saharan African intestinal microbiome

The archaeological incidence of ancient human faecal material provides a rare opportunity to explore the taxonomic composition and metabolic capacity of the ancestral human intestinal microbiome (IM). Following the recovery of a single desiccated palaeo-faecal specimen from Bushman Rock Shelter in Limpopo Province, South Africa, we applied a multi-proxy analytical protocol to the sample. Our results indicate that the distal IM of the Neolithic Middle Iron Age (c. AD 1485) Bantu-speaking individual exhibits features indicative of a largely mixed forager-agro-pastoralist diet. Subsequent comparison with the IMs of the Tyrolean Iceman (Otzi) and contemporary Hadza hunter-gatherers, Malawian agro-pastoralists and Italians, reveals that this IM precedes recent adaptation to Western diets, including the consumption of coffee, tea, chocolate, citrus and soy, and the use of antibiotics, analgesics and also exposure to various toxic environmental pollutants. Our analyses reveal some of the causes and means by which current human IMs are likely to have responded to recent dietary changes, prescription medications and environmental pollutants, providing rare insight into human IM evolution following the advent of the Neolithic c. 12,000 years ago.

microbiology↗