CSU professor finds rapid evolution in research on guppies

Seth Bodine

A Colorado State University professor is doing research on guppies to see how they evolve to different environments.

Professor and researcher Cameron Ghalambor states "If these fish were about the size of a trout, they could be the most popular pet fish because they are so beautiful."
Professor and researcher Cameron Ghalambor states “If these fish were about the size of a trout, they could be the most popular pet fish because they are so beautiful.” Photo: Maria Nateras

Biology professor Cameron Ghalambor has been researching gene expression in guppies who are exposed to environments with low predators. The research has found that guppies undergo rapid evolution when exposed to different environments.

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“We knew that guppies (have) this capacity to evolve very quickly, but we didn’t know how this would affect the pattern of gene expression,” Ghalambor said. “Our big question was what role does the environment play in inducing changes within individuals, and what’s the consequence of that across generations, in other words, evolutionary change.”

Ghalambor has been conducting experiments that involve placing guppies that are used to predators into an environment that have low predators. After three to four guppie generations, Ghalambor took them back to the lab for analysis.

Ghalambor found that the gene expressions of the guppies were plastic, or able to respond to the environment. A total of 135 genes showed rapid evolution and a change in their brains.

Associate Biology professor and neuroscientist Kim Hoke helps with analyzing the gene expression in the brains of the guppies.

“We’re really lucky that we can work on guppies because they are (an) amazing study system in which in every stream in Trinidad they live, (and) evolve in parallel,” Hoke said. “As a neuroscientist, I am really interested in the brain and behavior. We could have equivalently done this study in something else, but we know that the behaviors are also rapidly changing.”

These changes may not necessarily be a good thing, according to Ghalambor. The guppies initial response from the cue was to grow fast, but over time, the evolutionary response became slower.

“Most of the attention has been given to when plasticity is adaptive, when it’s helpful,” Ghalambor said. “That’s what people focus on. There’s been much less attention to situations like this when it’s not always helpful, at least initially. So if you can’t solve the problem through plasticity, you can’t solve the problem by evolving.”

The research is significant for the environment and evolution, according to Corey Handelsman, a zoology graduate student. He is currently analyzing data on changes in body shape from different environments

“From a very basic sense, just the understanding (of) how organisms interact with the environment and change across environments has huge implications for everything, from our understanding of evolution on a basic level to understanding medicine,” Handelsman said.

This research on evolution has been been going on for several years, and is still continuing because of its significance. 

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“This is a really general phenomenon of trying to understand what the earliest stages of evolution are, how that relates to immediate response in environment and then how that changes how you change in that environment,” Hoke said.

Evolutionary research can also translate into studying the effects of drug resistance and pesticides on crops, according to Hoke.

“Thinking about drug effects and also things like pesticides on crops, similarly there’s a lot of really rapid evolution,” said Hoke. “So thinking about how you could scale from small-scale tests on cell culture in a lab and look at the effects on drugs immediately on cells and pathogen interactions or plants and herbicide interaction, I think these things are really important for people to take into account.”

The guppy research is also significant for evolutionary biology and to CSU, according to Hoke.

“I think this research gives us a very unique picture of the earliest stages of evolution, and that’s something that people really don’t have access to most of the time,” Hoke said. “So, it’s great for CSU that we got to conduct this research here and provide this example of the amazing evolutionary biology we have at CSU. I think that we all know here that we have amazing evolutionary biology, but the word is more and more leaking out to the rest of the country.”

Collegian Science Reporter Seth Bodine can be reached at news@collegian.com or on Twitter @Sbodine120.