"Metagut"

Over at Science, an article about how hippos crapping prodigiously in their ponds means they share a lot of gut microbiome, as well as creating some fetid, deadly pools of water:

Hippos (Hippopotamus amphibius) already have a reputation for modifying their environment. At night, they head to shore to fill up on grass, then they return to the water to digest and excrete the leftovers, basically fertilizing the water. Gut bacteria help them digest these meals, and some escape in the dung excreted into the water. “Much of this dung is alive—microbially speaking,” says Douglas McCauley, an ecologist at the University of California (UC), Santa Barbara, who was not involved in the work.

Suspecting that gut microbes might survive outside the gut, researchers led by Christopher Dutton, an ecologist at the University of Florida, collected water from hippo pools along the Mara River, which flows through the Serengeti in Kenya and Tanzania. During the dry season, some of these pools—which can be up to the size of an ice hockey rink and can support a few to scores of hippos—get cut off from the river’s flow. The team sequenced RNA from hippo dung and the pools, choosing ones with moderate flow, low flow, or no flow to assess the impact of ever-more concentrated dung.

The more stagnant the pool, the more hippo gut microbes survived in the water, the team concludes today in Scientific Reports. The bacteria represented a “metagut,” in which one animal’s microbes could easily infect other hippos, the scientists say, possibly boosting the digestive capabilities and immune defenses of all the hippos in the pond. (There might be more pathogens as well, however).

"Metagut".  Lulz.