The influences of the microbiota on host physiology are so pervasive that the microbiota has been hypothesized to play a first-rate role in host evolution by shaping key host phenotypes (1). Nonetheless, to contribute to host evolution, traits need to be transmitted in the course of generations. One technique to evaluate whether some or all microbes are influenced by the genetic composition of the host, and therefore conserved in the course of generations, is by measuring heritability. Host species–explicit patterns in the composition of the microbiome—the genetic speak material of the microbiota—indicate there is some level of heritability in the microbiota (2). Nonetheless, studies evaluating variation in the microbiota and host genetics within a single host species private most frequently reported low heritability for a miniature share of microbial taxa (3). On page 181 of this downside, Grieneisen et al. (4) reject this typical conclusion by demonstrating that most gut microbiota traits in wild baboons stammer some level of heritability.