Kevin HuginsEvolution in the NewsApril 16, 2014

“Lifestyle determines gut microbes: Study with modern hunter-gatherers tells tale of bacteria co-evolution.”Science Daily, April 15, 2014.

This news article was about a journal article published in Nature Communications on

April 15, 2014. The article is the result of research that was led by scientists from the Max

Planck Institute for Evolutionary Anthropology. The purpose of the research was to study the

co-evolution of humans and gut microbiota and examine adaptation that resulted in groups that

had different diets. The primary group of interest was a hunter-gatherer group located in

Tanzania known as Hadza. This is one of the few remaining true foraging populations in the

world. The Hadza diet consists of baobab, game meat, honey, berries and tubers. Hadza do not

consume any agricultural crops or livestock.

Fecal samples from Hadza were analyzed for bacterial content. These samples were

compared with samples taken from Italians living in urban environments whose diet could be

considered a typical “western” diet. The results showed very different gut microbiota profiles

with Hadza having much greater diversity than the Italians. Some of the most notable points

were the presence of high levels of bacteria such as Treponema which is associated with disease

in western cultures, and low levels of bacteria such as Bifidobacterium which are considered

healthy in the west.

This study showed that the host and bacteria are a “supra-organism” that evolves together

in a mutually beneficial way. It also helps to shed some light on the ways that our ancestors may

have adapted to nutritional needs during the Paleolithic era.

Vocabulary:

Gut microbiota: The microbe population living in our intestinal tract which plays an important

role in health and nutrition.

Co-evolution: when two or more species reciprocally affect each other’s evolution.

Supra-organism: Used to describe the combined activities of a host and microbiome when they

represent both a shared target for natural selection and a driver of adaptive responses. The host

and microbiome work together as a single organism.

References:

Max-Planck-Gesellschaft. (2014, April 15). Lifestyle determines gut microbes: Study with

modern hunter-gatherers tells tale of bacteria co-evolution. ScienceDaily. Retrieved April 15,

2014 from www.sciencedaily.com/releases/2014/04/140415133924.htm

Schnorr, S. L. et al. Gut microbiome of the Hadza hunter-gatherers. Nat. Commun. 5:3654 doi:

10.1038/ncomms4654 (2014). Retrieved April 15, 2014 from

http://www.nature.com/ncomms/2014/140415/ncomms4654/full/ncomms4654.html