American scientists have found that a specific enzyme, synthesized by the bacterium Vibrio fischeri, causes a splash in reproduction at the choanoflagellates Salpinogoeca rosetta. Protozoa collect in aggregation, where genetic recombination takes place, and actively divide. This discovery first showed that bacteria can influence the reproduction of eukaryotes. As the authors note, this may mean that bacteria (for example, living in the intestine) can have an effect on the reproduction of animals, especially since the choanoflagellates are our closest relatives from the world of protozoa. In addition, it is shown that, for example, the intestinal microflora of red cockroaches secretes pheromones that promote their aggregation, and the transplantation of brown bears microflora to mice causes them to prepare for hibernation.