To stay healthy, humans and some other animals rely on a complex community of bacteria in their guts. But research is starting to show that those partnerships might be more the exception than the rule.
“Every organism that exists has three and a half billion years of evolutionary history behind it, many millions or tens or hundreds of millions of which are not shared with organisms that we use as models,” Sanders said. Scientists’ emerging awareness of the diverse relationships that animals share with microbes “should make us really cautious about drawing inferences using fruit flies as models for gut microbiome importance or interactions, because fruit flies might be operating from a very different fundamental starting point compared to humans. It’s the same thing with mice.”
