The tighter the integration, the more closely intertwined the fates of host and microbe become. For such holobionts, Bordenstein says, you can’t understand the evolution of either the host genome or the microbial genomes in isolation because the community of organisms as a whole shapes the traits of the individual. “We need to understand what the microbes make, what the host makes and potentially how those products work together,” he said. The holobiont, he argues, adds up to more than the sum of the host and microbes. Out of their interaction emerges a coherent entity that natural selection might act on alongside other units of selection, like the individual or a gene.
~ Jonathan Lambert
I’m am fascinated by the reality that there are countless microbes which coinhabit our body.
… the microbes are holding the reigns to a lot of what’s going on. If we were not doing a good job at passaging them around to additional culturing flasks — specifically other humans — they would undoubtedly discover ways to make us better at doing that.
I think a more optimistic, or different way to frame this, is just that we’re composite organisms. I think we traditionally think of ourselves — the human body — as a collection of human cells. And what we really are is an ecosystem. We have microbial and human parts that come together to work in a concerted fashion to make up this
super-organism. And we can’t forget about the microbes because they’re really an important part of our biology.
~ Dr. J Sonnenburg
If you haven’t heard much about how important are all the teeny little microbes living in your digestive track, this is a good podcast to get started.
The agent of our immunological misery is the disappearance of something we co-evolved with in a mutually beneficial relationships: microbes and parasites that have lived inside our bodies for millennia.
This new hypothesis is brilliantly summarized in a recent book by Moises Velasquez-Manoff: An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Disease.
~ Todd Becker