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There are calls for research into the historical evolutionary relationships between humans and their commensals, as it would greatly inform models that predict the spread of pests and diseases under urban population expansion. The earliest civilizations emerged approximately 10 000 years ago and created conditions ideal for the establishment and spread of commensal urban pests. Commensal relations between humans and pests likely emerged with these early civilizations; however, for most species (e.g. German cockroach and black rat), these relationships have formed relatively recently—within the last 5000 years—raising the question of whether others could have emerged earlier. Following comparative whole genome analysis of bed bugs,Cimex lectularius, belonging to two genetically distinct lineages, one associated with bats and the other with humans, coupled with demographic modelling, our findings suggests that while their association with humans dates back potentially hundreds of thousands of years, a dramatic change in the effective population size of the human-associated lineage occurred approximately 13 000 years ago; a pattern not found in the bat-associated lineage. The timing and magnitude of the demographic patterns provide compelling evidence that the human-associated lineage closely tracked the demographic history of modern humans and their movement into the first cities. As such, bed bugs may represent the firsttrueurban pest insect species.
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How there got to be so many of us. The evolutionary story of population growth and a life history of cooperation
One of the defining features of human evolution is our demographic success. As of August 2019, the world’s population exceeds 7.7 billion. The human capacity for population growth has profound effects on people’s lives today, but it is also one of the remarkable stories of our evolutionary past. Although most research and public attention has centered on the past 200 years, when growth has increased exponentially, global population growth prior to that was not trifling. Before the industrial era, humans populated all of the world’s environments with more than a billion people. Importantly, it was deep in the past when the biological and social underpinnings were established that allow humans to excel as reproducers and survivors. The evolutionary trends in fertility and survival that gave rise to human demographic success were fundamentally shaped by our ability to cooperate. This essay focuses on how the human dietary niche and life history presented novel opportunities for cooperation that tied younger and older generations together in ways that gave us our demographic edge
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- Award ID(s):
- 1632338
- PAR ID:
- 10205662
- Date Published:
- Journal Name:
- Journal of anthropological research
- Volume:
- 75
- Issue:
- 4
- ISSN:
- 2153-3806
- Page Range / eLocation ID:
- 472-497
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1086/705943
