‘We can no longer ignore diseases in the deep human past’: Malaria influenced early humans’ migrations across Africa, study suggests
The risk of malaria influenced where prehistoric people lived in sub-Saharan Africa, a new study suggests.
The research is the first to link early human habitation to deadly disease and contrasts with early hypotheses that prehistoric people migrated to different regions primarily for safety reasons. agricultural reasons.
“For a long time, it was thought that infectious diseases only really became a problem with the advent of agriculture, and this was particularly true for malaria,” co-author of the study. Éléonore Scerrian archaeologist at the Max Panck Institute for Geoanthropology in Germany, told Live Science in an email.
But the study by Scerri and colleagues, published April 22 in the journal Scientific advancessuggests that humans have avoided settling in areas with a high risk of malaria for more than 70,000 years.
“Our work shows that we can no longer ignore diseases from the deep human past,” she said. “They don’t just have a small effect, they have – in the case of malaria, at least – transformative impacts that have helped shape who humans are today.”
Malaria risks
The study authors used data from previous studies to reconstruct the climate of sub-Saharan Africa over the past 74,000 years, at intervals between 1,000 and 2,000 years.
Then, they calculated a “malaria stability index” for each area at each stage, based on modern epidemiological data and the probability that an area contains habitats for the Anopheles kind of mosquito. Female bites Anopheles mosquitoes transmit the parasite Plasmodium falciparum to humans, which causes malaria.
By comparing this index to maps of early human settlements, the authors showed that prehistoric hunter-gatherers in sub-Saharan Africa actively avoided high-risk malaria hotspots. The researchers said this behavior, in turn, helped determine human population structures at least 13,000 years ago, several thousand years before the introduction of humanity. agriculture.
“The key message of our article is that malaria was already a problem before agriculture,” co-author of the study. Andrea Manicaan evolutionary ecologist at the University of Cambridge, told Live Science. But “the situation probably became even worse after people became sedentary and settled at high density due to food production.”
Mosquitoes of the genus Anopheles can carry the parasite responsible for malaria.
(Image credit: Paul Starosta via Getty Images)
The study suggests that central West Africa was hardest hit, he added, and that the region remains a malaria hotbed today.
“Archaeology in central and west Africa is limited, but a number of finds are consistent with the idea that populations in this region were very fragmented,” Manica said.
Malaria hotspots
The study is the first to suggest that the location of prehistoric human settlements was influenced by the risk of disease, rather than simple climatic changes – although wetter and warmer weather would have encouraged populations of disease-carrying animals. Anopheles mosquitoes.
“The role of disease in the deep human past, particularly in the early African phases of our species’ prehistory, has not been well studied because we lack ancient evidence. DNA of these periods,” Scerri said.
But the new study showed how to overcome the lack of evidence. “We have developed a pipeline that can explore a number of vector-borne diseases,” Scerri said. “This is an exciting development and we hope it will open a new area of research.”
“We have shown that it is possible to trace a disease back in time and assess its potential impact on past habitations,” Manica added. “The next phase is to start exploring other diseases in addition to Plasmodium falciparum to see their role.”
Simon Underdowna biological anthropologist at Oxford Brookes University in the United Kingdom, who was not involved in the new study, said he agreed with the study’s findings.
“Disease has always been with us, and it actually shaped what humans could do, where humans could move,” he told Live Science.
Colucci, M., Leonardi, M., Blinkhorn, J., Irish, SR, Padilla-Iglesias, C., Kaboth-Bar, S., Gosling, WD, Snow, RW, Manica, A. and Scerri, EML (2026). Malaria has shaped human spatial organization over the past 74,000 years. Scientific advances, 12(17), eaea2316. https://doi.org/10.1126/sciadv.aea2316
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