Paul Myers joined the Biology Discipline at UMM back in 2000 and brought with him a wealth of experience in zebra fish research. However, it wasn’t his initial intent as a bio undergrad to one day find himself in a lab full of aquariums.

"Originally, I was interested in the functions of the human brain,” he recalls. “But first, I needed a simple model to work with. Fish are simple, especially young fish, so that led me to the area of early brain development.”

Myers found zebra fish to be well suited to his research because of their rapid development. Eggs are laid one morning and the next day, young fish in the eggs with simple reflexes can be studied. They hatch after only two days.

Zebra fish are now a hot scientific model, according to Myers. Researchers currently explore everything from mutations to genomes with these little fish. “When I started working with zebra fish, there were six of us studying them. Now there are thousands,” he says.

Myers’ research is currently focused in two areas. The first is to study the cellular effects of ethanol on zebra fish embryos. His research has direct implications for those who want a clear understanding of the effects of fetal alcohol syndrome on human embryos.

“Obviously this research can’t be done on human embryos, but we can study the effects of different alcohol solutions on young fish,” says Myers. “Unlike mammal embryos, zebra fish embryos reside in transparent eggs and are transparent themselves. Zebra fish are also cheap, and they lay lots of eggs.”

He has enlisted the help of student research assistants to gather and analyze data on this project. Two years ago, Matt Larson (now in med school), took his ethanol effects research to the National Developmental Biological Society Conference and was awarded the Best Undergraduate Presentation award. This year, Senior Amanda Woodle (who has been accepted to the Duluth medical school) is continuing the ethanol study.

Stupid fish tricks
In addition to their many research attributes, zebra fish also have well-established, distinct genetic lines that can be studied. This is a great advantage in Myers’ second area of research; the genetics of stupid behaviors in fish. What might at first sound like a bad lab joke has a real impact in the commercial world of stocking game fish in the wild.

One of the problems with raising captive game fish for release is that the successful ones have learned to adapt to conditions which don’t mimic natural circumstances. As an example, game fish raised for release are fed on the surface of the water. In the wild, surface feeders would get picked off by predators more easily. But in captivity, surface feeders get the most food, are larger and healthier and therefore, selected for breeding. The results? Stupid fish.

“These less cautious fish don’t give anglers much of a challenge,” notes Myers. “Sports fishermen prefer smart fish. So this is a real issue on lakes that are being stocked.”

Zebra fish offer a useful opportunity to study this wild/captive behavioral problem because of their own domestication as tank fish. Zebra fish were first collected by the British in the 1830s. Over time, researchers began to notice that lab-bred fish were not as smart as their wild counterparts. In recent years, researchers were able to collect small numbers of wild specimens from Nepal, Thailand and locations on the upper Ganges River. These smarter, wild fish and their descendents are timid, afraid of people, and have different feeding behaviors compared to lab fish.

Myers was able to obtain some fish from this wild genetic line to compare their behaviors with his own lab fish. His research student, Mike Peterson, is working on quantifying their differing behavioral responses to light and dark, feeding and the movement of large objects.

“Once behavioral differences have been quantified, we can cross breeding lines to find out what comes out,” says Myers. “And if we can isolate strains of fish with certain behaviors, molecular biologists can in turn examine that to find out what’s going on.”

Once a biologist who was drawn to zebra fish as a cheap way to study early brain development, Myers now finds their behavioral quirks as a species worthy of study.

“These fish are both social and cannibalistic,” he observes. “There must be evolutionary tradeoffs for that. In a tank colony, for instance, only one or two large females make eggs. The others follow her and her mate to eat eggs as they’re released. It’s exhausting for the female, but she also makes the choice each day as to whether she’s going to lay eggs or follow some other female laying eggs to eat them. How does she decide on a given day whether to eat or lay?”

This and other zebra fish behaviors could all warrant further research with the right student assistant. Myers knows that the best plan is to wait for a curious student to come to him.

“They seek you out when the research you’re doing interests them,” he says. “There’s certainly interesting stuff here to look at in dominance hierarchies and territorial behavior. I’m just waiting for a student who’s interested in studying this. Then, all you need is a fish net.”