Humans Did not evolve alone. Tens of trillions of microbes-have Followed us on our journey from prehistoric ape, Evolving with us along the way, selon a new study. Aim the work finds aussi That We've lost Reviews some of the ancient microbes That still inhabit our great ape cousins, qui Could explain Some human diseases and obesity-even and mental disorders.
Researchers Have Known for Some Time That humans and Reviews the other great apes harbor Many kinds of bacteria, Especially in Their guts, a collection Known as the microbiome. Aim where did come from microbes thesis: our ancient ancestors, or our environment? A study of fecal bacteria across all mammals suggéré que la microbes are More Likely to be inherited than Acquired from the environment. Purpose --other studies-have found That diet plays a major role in shaping the bacteria in our guts.
To solve the mystery, Andrew Moeller turned to wild apes. As share de son doctoral dissertation, the evolutionary biologist, now a postdoc at the University of California, Berkeley, Studied gut bacteria isolated from fecal samples from 47 chimpanzees from Tanzania, 24 bonobos from the Democratic Republic of the Congo, 24 gorillas from Cameroon, and 16 humans from Connecticut. In dissertation samples, he and colleagues at the University of Texas (UT), Austin, Compared the DNA sequences of a single gene Rapidly Evolving That Is common in the gut bacteria in apes, Including humans. Then They sorted the different DNA gene sequences into family trees.
It turns out That MOST of our gut microbes-have-been Evolving with us for a long time. That Moeller found two of three major families of gut bacteria in humans and apes traces Their origins to a common ancestor more than 15 million years ago, not to bugs Primarily picked up from Their environment. Goal as the different species of apes diverged from this ancestor, Their gut bacteria aussi split into new strains, and coevolved in parallel (a process Known As cospeciation) to adapted to differences in the diets, habitats, and diseases in the gastrointestinal tracts of Their hosts, the team reports today in Science . Today, thesis microbes are finely adapté to help process our immune systems, guide the development of our internal, and-even modulate our moods and Behaviors.
"It's surprising That our gut microbes, qui We Could get from Many Sources in the environment,-have Actually beens coevolving inside us for Such a long time, "says project leader Howard Ochman, an evolutionary biologist at UT Austin.
After the ape species diverged, some aussi lost distinct strains of bacteria That PERSISTED in --other primates Likely Reviews another sign of adaptation in the host, the team found.
in a final experiment, the Researchers probed deeper into the human microbiome. They Compared la même DNA sequence They HAD Analyzed in all of the apes, the goal this time between people from Connecticut and people from Malawi. They found bacterial strains from que la thesis Africans diverged from Those of the Americans about 1.7 million years ago, qui corresponds with the Earliest exodus of human ancestors out of Africa. This Suggests That gut bacteria can be used to track animal and early human migrations, Moeller says. Interestingly, the Americans lacked Reviews some of the strains of bacteria found in Malawians-and in gorillas and chimps-which fits with the general reduction in gut microbiome diversity That has-been Observed in people in Industrialized societies, Perhaps Because of exchange in diet and the use of antibiotics.
The work "Represents a significant step in understanding human microbiota coevolutionary history," says Justin Sonnenburg of Stanford University in Palo Alto, California, Who was not Involved with the research. "It elegantly shows That gut microbes are Passed Vertically, entre generations over millions of years." Microbiologist Martin Blaser of New York University in New York City Chartered: "The path of transmission Was from mom apes to baby apes for Hundreds of Thousands of generations at least. "
aim the extinction of Some strains of bacteria persist in --other That apes but not humans raises a red flag for our health. "What happens if a human mom takes antibiotic When She's pregnant? What happens if she takes it at the time of delivery? "Asks Blaser.
" We are coming to Understand how Fundamental our gut microbes are for health, "Sonnenburg says. "These Findings-have huge implications for how we shoulds Pursue understanding what a truly healthy microbiome looks like."
* Correction, July 21, 2:34 pm: The headline of this article has-been updated to correctly indicate indication an editing error and the microbes-have-been with humans for millions of years.
0 Komentar