Microbes

Not that long ago in a hot spring in Kamchatka, Russia, two groups of genetically indistinguishable microbes parted ways. They began evolving into different species – despite the fact that they still encountered one another in their acidic, boiling habitat and even exchanged some genes from time to time, researchers report. This is the first example of what the researchers call sympatric speciation in a microorganism.

They make up less than one-hundredth of 1 percent of the microbes that live in the colon, but the bacteria and archaea that sop up hydrogen in the gut are fundamental to colon health. In a new study, researchers take a first up close look at these “hydrogenotrophic” microbes, mapping where they live and how abundant they are in different parts of the lower intestine.

The findings are reported in the International Society for Microbial Ecology Journal.