What guppy guts can teach us about evolution

On the list of scientific tools that help us understand health, evolution or the environment, the Trinidadian Guppy doesn't often come to mind.

In Trinidad, the wild guppies are almost taken for granted, as they are often thought of as aquarium pets in the U.S.

In Trinidad, they are called drain fish and locals would ask why we were studying them.

"Guppies in Trinidad are kind of like squirrels in Michigan," said Sarah Evans, an associate professor and Fitzpatrick's departmental colleague in the College of Natural Science.

Thanks to a unique combination of biology and ecology, the guppies have provided researchers with insights into evolution for decades. Evans and Fitzpatrick have shown the potential of the guppies to help answer big questions about how microbes living in host organisms contribute to health, survival and quality of life.

The results of a research team led by the Spartans were published in the journal Proceedings of the Royal Society B: Biological Sciences.

The collection of microbes that live in the gut of a host is becoming more and more clear that it plays an important role in the well-being of its host. Human health is tied to our gut microbiome.

Evans and Fitzpatrick are interested in some of the big-picture questions of biology and wanted to better understand how the microbiomes change as organisms evolve.

Evans, who is a core faculty member of the EEB, said that the microbiome affects fitness and can affect evolution.

There are many examples of this in nature. Along their evolutionary path, termites have adapted to welcome populations of single-celled protozoans into their guts that allow them to digest wood.

Another example is giant pandas. pandas eat only leaves Pandas can more closely resemble their relatives than some of their plant-eating kin. The shape and size of the panda's gut is likely to be the reason for that.

As host organisms evolve, Evans and Fitzpatrick wanted to better understand what the biggest drivers of the microbiome are. It could be things like gut shape, diet or characteristics of a new environment, which could be foreign to the host. The researchers knew that guppies could lend a fin.

Trinidad is a continental island that split off from South America a long time ago. There is a continuation of the northernmost part of the mountain range.

In independent systems, the rivers and streams run down the mountains. Each water system has its own guppies that are independent of each other.

In the 1950s, evolution researchers realized that they could take guppies from one environment and put them in another. The native populations in those low-predator environments would be reflected in the genes and traits of the fish. Transferring fish from low-predation sites to high-predation streams would make them adapt.

And it is repeated. Evans said that the system is in textbooks because they evolve in many of the same ways.

Given that we know guppies evolve really fast in parallel ways, we could ask how the microbiome changes as they evolve.

The sites where Evans and Fitzpatrick returned were where scientists used to study the evolution of the choovy. They went to more than a dozen different sites and took samples of fish that had been moved closer to 60 years ago.

Evans and Fitzpatrick collaborated with experts from Brazil to find out how the guppies' microbiomes changed in response to their environment. The shape of the guts that drive what types of microbes survive there has changed more quickly than expected.

Their gut microbe populations did not match those found in the fish native to a particular environment. The function of the microbiomes was the same despite the mismatch. The native microbes were doing the same thing as the transplants.

The idea for this study was created years ago by Evans and Fitzpatrick. The idea was a result of the strengths of Evans and Fitzpatrick.

Fitzpatrick said that it was the exciting thing about interdisciplinary collaborations, merging ideas and expertise.

The two went to Trinidad to collect samples for a side project. Since then, they have been starting up their own research labs, making it difficult to find time to complete the project.

The work of those affected by the coronaviruses, especially women and caretakers, has been published in a special issue of the Proceedings of the Royal Society B: Biological Sciences.

Fitzpatrick said they were glad to support the issue.

The research went through a rigorous peer-review before it was published. Some of the typical criticisms of a study like this were heard by the researchers.

Some reviewers think that the system is too messy and doesn't give researchers enough control. It is not messy enough for some. The guppies have a unique ecology, and they wonder how much of it can be applied in nature. guppies don't let perfect become the enemy of good because no study is perfect.

Evans said that they were in a sweet spot.

More information: S. E. Evans et al, Shifts in gut microbiome across five decades of repeated guppy translocations in Trinidadian streams, Proceedings of the Royal Society B: Biological Sciences (2022). DOI: 10.1098/rspb.2021.1955 Journal information: Proceedings of the Royal Society B Citation: What guppy guts can teach us about evolution (2022, May 27) retrieved 27 May 2022 from https://phys.org/news/2022-05-guppy-guts-evolution.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.