Summary: The scientist proposed that natural selection acting on microbes caused them to be more successful when they manipulate the host by changing its behavior, for example by making it more social in order to have a chance to spread to other hosts. That also explains why a person that has received an act of kindness is more likely to reciprocate it, starting what is called a “snowballing effect” of favors, and probably microbial spread.
Connections: This article connects to the lecture about the human microbiome, and how the kind of microbes living in and on us can affect not only our health, aging, and energy levels, but also our behavior.
Analysis: This research is extremely important in more than just the field of human medicine; it has the ability to influence what we think we know about ecology and relationships among animals, such as ants/bees and other social insects and animals caring for offspring that is not related to them. It could be considered one of the main theories about the evolution of altruism, and the first to consider factors other than genetics.
Questions: What happens if the microbe and the host have conflicting interests? How can the host avoid being controlled by its microbes? What is the effect of antibiotics or probiotics on the behavior of the host? Which microbes are able to manipulate their hosts?