Certain types of bacteria can mutate to reproduce more quickly when exposed to microgravity, and that's not great news for our space tourist dreams, seeing as we humans are teeming with bacteria.
It's not clear why these bacteria respond so positively to microgravity, but researchers are figuring out ways to protect astronauts out in space, as well as mitigating the damage should a space-modified colony ever find its way back to Earth.
In a study published in 2017, researchers from the University of Houston monitored Escherichia coli cells through 1,000 generations of growth in simulated microgravity conditions, finding that it spread significantly faster than a control sample of unaltered bacteria.
The E. coli cells also picked up at least 16 different genetic
mutations along the way, though it's not clear how these mutations affect growth rates, either individually or as a group.
"This study is broader in scope than previous ones on two counts," one of the team, Jason Rosenzweig, told Leah Crane at New Scientist at the time.