Can economics help explain microbial life?

Adam Smith was a famous 18th century economist, not a biologist, but could his economic theories help solve longstanding mysteries about gut microbes? The authors of a new PLOS One study seem to think that’s the case.
Joshua Tasoff, an economics professor at Claremont Graduate University, and colleagues from Boston and Columbia Universities report in their new study that the same framework that is used to explain how societies buy, sell, and trade goods and services could also be applied to microbial life, and could help answer larger questions about biological evolution and productivity.
“As an economist, I don’t normally get to experiment with a living organism’s DNA,” Tasoff, who conducted the research along with Michael Mee from the BU Department of Biomedical Engineering and Harris Wang of the Columbia Department of Systems Biology, said.
“By developing an economic framework of microbial trade, we can use off-the-shelf economic concepts and theories to better understand how these microbial communities work,” he added in a statement. The authors said that their findings offer new insights into these tiny life forms.
Increasing production caused bacterial communities to thrive
While they are far too small to see with the naked eye, microbes can be found in the air, the soil, and even within the human body, the researchers explained. Bacterial cells even outnumber the human cells found in a person’s body by 10-to-1, and while some of them cause disease, most of them are vital to sustaining life.
Microbes also interact with one another in complicated, but not yet well understood ways. They live in complex communities where they need to exchange molecules and proteins in order to survive, the study authors stated. These resources are traded between microbes in much the same way that modern societies exchange goods and services in order to grow and thrive.
These similarities inspired Tasoff and his colleagues to apply the general equilibrium theory of economics to microbes. The theory was used to explain resource exchange in complex economies as a way of understanding the trade of resources in microbial communities. They used synthetic E. coli and manipulated bacterial cells to alter their production and export rates.
They then tested the population growth implications of the theory, and found that the increase in trade caused microbial communities to grow faster, and that while all of the bacteria benefits from trade, those that predominantly exported their “goods” grew more slowly than those that predominantly imported.
“That means that species face a tradeoff between growing their communities faster versus increasing their own population relative to that of a trading partner,” Tasoff said, adding that the findings could lead to the application of other economic concepts which could help scientists better understand microbial communities, as well as those of other biological organisms.
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