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Are the pathogens of out-groups really more dangerous?
1The Hygiene Centre, Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, United Kingdom. micheal.debarra@lshtm.ac.uk
The Behavioral and Brain Sciences
|February 1, 2012
Summary
This study challenges the idea that local pathogen-host evolution makes outside groups more dangerous. It questions the theory that pathogens from other groups are more harmful than those within one's own family or religious community.
Area of Science:
- Evolutionary biology
- Pathogen-host interactions
- Human social behavior
Background:
- The pathogen-host coevolution theory suggests that pathogens evolve to overcome host defenses.
- Fincher & Thornhill proposed that localized coevolution leads to greater pathogen virulence in out-groups.
Purpose of the Study:
- To critically evaluate the plausibility of Fincher & Thornhill's hypothesis.
- To examine the relationship between localized pathogen-host coevolution and perceived pathogen threat in different social groups.
Main Methods:
- Review of existing literature on pathogen virulence and host specificity.
- Theoretical analysis of coevolutionary dynamics in human populations.
- Examination of social and ecological factors influencing pathogen transmission.
Main Results:
- The proposed link between localized coevolution and increased out-group pathogen damage is not robustly supported by current evidence.
- Alternative explanations for pathogen distribution and perceived threat exist.
- The complexity of pathogen-host dynamics and social structures complicates direct causal links.
Conclusions:
- The Fincher & Thornhill argument regarding out-group pathogen virulence requires further empirical validation.
- Understanding pathogen-host coevolution necessitates consideration of broader ecological and social contexts.
- Future research should focus on nuanced models that integrate genetic, environmental, and social factors.
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