animalsaccording to lutz the unique relationships bats have with gut bacteria may be related to another trait that sets them apart from their fellow mammals their ability to flybats have extremely shortened guts she saidthe study noted that food takes only fifteen to thirty minutes to pass through a bats digestive system a third the time it takes for a similarlysized rodentthis the researchers speculated is because a long winding digestive tract may weigh the bats down and affect their flightfor bats you cant be carrying around nonessentials you need to reduce weight for flyingyou dont want a heavy gut lutz saidthe study also noted that the gut bacteria ecosystem in bats resemble those of birds more than what is seen in mammalsthe researchers cautioned that due to weaker dependence on gut microbes bats may be impacted more severely by environmental changesbats may be very susceptible to environmental change if they have a transient microbiome they might not have the most stable defense mechanisms humancaused disturbances to the environment are a very important issue bats may be extrafragile and more at risk lutz said