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Abstract Among mammals, humans are exquisitely sensitive to lipopolysaccharide (LPS), an environmentally pervasive bacterial cell membrane component. Very small doses of LPS trigger powerful immune responses in humans and can even initiate symptoms of sepsis. Close evolutionary relatives such as African and Asian monkeys require doses that are an order of magnitude higher to do the same. Why humans have evolved such an energetically expensive antimicrobial strategy is a question that biological anthropologists are positioned to help address. Here we compare LPS sensitivity in primate/mammalian models and propose that human high sensitivity to LPS is adaptive, linked to multiple immune tactics against pathogens, and part of multi‐faceted anti‐microbial strategy that strongly overlaps with that of other mammals. We support a notion that LPS sensitivity in humans has been driven by microorganisms that constitutively live on us, and has been informed by human behavioral changes over our species' evolution (e.g., meat eating, agricultural practices, and smoking).
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The complexity of human computation via a concrete model with an application to passwords
Significance This work presents a concrete, mathematically precise model of what humans can compute in their heads. It thereby provides a method to probe the limits of human computation (can humans generate numbers that look random to a powerful computer?) as well as to design efficient humanly computable mental algorithms for everyday tasks, such as generating passwords and making real-time decisions.
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- Award ID(s):
- 1717349
- PAR ID:
- 10144514
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 117
- Issue:
- 17
- ISSN:
- 0027-8424
- Format(s):
- Medium: X Size: p. 9208-9215
- Size(s):
- p. 9208-9215
- Sponsoring Org:
- National Science Foundation
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