"Your gut bacteria predates appearance of humans", Guardian article

[sarah darwins]

Interesting Guardian article (picked up from a paper in Science, to which I don't have access).

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Guardian link: https://www.theguardian.com/science...ates-appearance-of-humans-genetic-study-finds

Science link: http://science.sciencemag.org/content/353/6297/380
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The perspective is evolutionary but there are obvious implications for health.

The research suggests that microbes in our ancestors’ intestines split into new evolutionary lineages in parallel with splits in the ape family tree.

This came as a surprise to scientists, who had thought that most of our gut bacteria came from our surroundings - what we eat, where we live, even what kind of medicine we take. The new research suggests that evolutionary history is much more important than previously thought.

“If our gut bacteria have been tracing our human lineage for millions of years, it could be used to reconstruct the path of human migration. Different populations likely have different strains of the gut bacteria,” he [Prof Andrew Moeller of the University of California, Berkeley who led the study] said, noting that a comparative sample of human gut bacteria in Malawi showed slightly different microbiomes than the Americans.

That, he adds, could have implications for the burgeoning use of faecal transplants - often used in patients whose own gut bacteria have been suppressed with antibiotics. “It’s a very positive enterprise, but our results suggest those efforts need to consider that our bacteria are tracking our lineage.”

Whenever I read this kind of thing, I wonder why we aren't routinely doing metagenomic gut profiles on neonates. The current testing might be imperfect, and the future uses uncertain, but there seems little doubt that precise manipulation of the microbiome will be a big part of future medicine. Wouldn't it be sensible to start getting baseline profiles for newborns right now? Is anyone already doing this?

 

[sarah darwins]

Another thought occurs. That article suggests that the gut microbiome is hardly dependent on environment, yet I thought there was much research showing the opposite. I wonder if this is a misreading of the original paper. Only the other day someone here on PR mentioned dramatic differences in gut flora between people living in post-industrial societies and people living in largely undeveloped regions.

I keep seeing apparently contradictory assertions about the microbiome.

 

[JPV]

I keep seeing apparently contradictory assertions about the microbiome.

That's because nobody knows what they're talking about yet.

 

[Daisymay]

Thanks for posting, very interesting.

Is this not one of these findings which is surprising initially but then it makes sense that gut bacteria would have to evolve in tandem with speciation, otherwise the new species wouldn't evolve and thrive?

Wouldn't animals evolving to fill some new niche, where they feed on some slightly different food sources, need an altered microbiome to cope with that slightly different food source?

And the environment would and still does impact the microbiome for good or bad, so it's an ongoing interaction over the millenia between this ancestral microbiome and the changing environment.

And now, with changes in food production, diet, pollution, antibiotics,etc etc the microbiome is having to cope with multiple rapid environmental changes, at a rate never before experiences.

 

[sarah darwins]

Wouldn't animals evolving to fill some new niche, where they feed on some slightly different food sources, need an altered microbiome to cope with that slightly different food source?

Someone in the Guardian comments raised the slightly alarming possibility that it was the bacteria's speciation that was driving the mammalian one ... a bit like Douglas Adams' famous mice (perhaps they're the ones experimenting on us!)

 

[ScottTriGuy]

...possibility that it was the bacteria's speciation that was driving the mammalian one...

hmmmm, interesting....perhaps similar to the notion that the first domesticated animal was the human.

Wheat did the domesticating.

 

[worldbackwards]

"Your gut bacteria predates appearance of humans"

...but Guardian science writers probably appeared a few millennia before that.