A new study shows that our peers who live on our tongues are not randomly mixed,media reported. Instead, they seem to prefer to live with their own peers and divide them into different groups according to their race. The researchers started scratching the tongues of 21 healthy volunteers. They then use fluorescent labels to identify specific groups of bacteria, some of which provide nutrients, so they can see exactly where each bacteria is on the surface of the tongue.
The bacteria, without exception, form a tight, clear cluster of the same species, the researchers said march 24 in Cell Reports.
Under a microscope, these clusters (above) act like a microbial rainbow. For example, red line bacteria grow near the epithelial tissue of the tongue, while cyan Rothbacteria bacteria form long patches between other communities. Green streptococcus forms a thin skin at the edge of the tongue and a thin vein inside.
By looking at these images, researchers can guess how these colonies build up and grow over time.
Although scientists have learned from DNA sequencing which microbes are present in the human body, this is the first time they have been able to observe the tongue’s microbiome in such detail.
Looking at where different species gather and how they organize, the researchers say, could reveal more information about how bacteria work and how they interact.