Communal Microbes 


The behavior of microorganisms presents a paradox that puzzles the confident logic of science: some microbes can cease performing a function that had been considered necessary for their survival, yet this seeming disparity causes them to thrive and proliferate.

A progressive group of microbiologists explain that while these microbes seem to be discarding vital functions, they are really just finding others to get these essential tasks done for them. This particular adaptation encourages microorganisms to live in cooperative communities.

This idea is called The Black Queen Hypothesis, named after the queen of spades in the card game Hearts, in which the popular strategy is to avoid picking this card. Accordingly, the loss of the microbe’s ability to satisfy its own vital needs is instead an evolutionary efficacious strategy for certain communal microbes. These microbes can live together more resourcefully if they get rid of certain behaviors and rely on others to help them meet their needs.

Richard Losick of Harvard says that the Black Queen Hypothesis offers a new way of understanding how complex, inter-dependent communities of microorganisms thrive. Cooperative and even altruistic behavior abounds beyond the microbe world: bats feed hungry friends, honeybees commit suicide to defend the hive, birds raise offspring that aren’t their own, and humans leap in front of traffic to save total strangers. The biological success of certain species, like ants, depends entirely on their ability to cooperate and form structured societies based on shared sacrifice.

Cooperation may no longer be thought of as an ideal confined to the imaginations of dreamers: it may not be the exception, but rather the rule, or at least part of the rule. This hypothesis may spur a new evolutionary theory, or at least call for a rereading of the standard one, for it recognizes that a dog-eat-dog concept of nature is limited. After all, we are tuned to cooperate, not merely compete.

Image: "Working Together Teamwork Puzzle Concept" by lumaxart on Flickr courtesy of a Creative Commons License.