January 10 2006
If you felt threatened, would you seek safety in the familiar company of relatives or would you seek out a large crowd of strangers, figuring there is safety in numbers?
If you were a tadpole, odds are you'd abandon your brothers and sisters and go hang out with a large crowd, research in Indiana State University's Department of Life Sciences suggests.
Rusty Gonser, assistant professor of life sciences at ISU, tests the acidity of water in which hundreds of tadpoles are living while graduate student Travis Kamm looks on.
It takes just a few weeks for a tadpole to fully develop into a toad or frog. Even in their earliest stages, scientists have long recognized that amphibians - like most creatures - tend to cluster with their relatives, or kin.
But Travis Kamm, a graduate student from Raleigh, N.C., saw a void in existing research and set out to fill that void, seeking to determine the circumstances that would make tadpoles chose a small, somewhat safe group of kin or a large group of "non-kin" that would be more safe from predators.
Over the past two years, Kamm set up cameras to monitor tens of thousands of tadpoles to see just what happens when the tadpoles feel threatened.
"When you add a predator, such as a bluegill, they do in fact switch that strategy and they choose to go with the larger group because, in the presence of a predator large groups are safer," Kamm said.
Scientists don't know how tadpoles recognize relatives or what makes them seek safety with strangers when in danger. Kamm's professor says his study suggests the thought processes of amphibians may be more complex than originally believed.
"It gets to that core debate: Is it nature or is it nurture? And it even says something about genetics. Even if this is genetically hard-wired, it says there's something in there that still allows them to make complex decisions," said Rusty Gonser, assistant professor of life sciences.
Travis Kamm, a graduate student in life sciences at ISU, tests a water sample to ensure proper nutrient levels for tadpoles
"I saw that there was sort of a gap that other researchers had left out and so it just adds a little piece to the big puzzle that we're all trying to figure out," said Kamm, who completed his bachelor's degree at St. Louis University.
He chose Indiana State to pursue his master's degree because he and Gonser share some of the same research interests and because he had more of a say in his own projects.
"I came here because of the freedom to choose my research. I wasn't stuck on a project that I had no interest in, whereas in a lot of graduate programs you don't get to choose what you're going to do, " Kamm said.
Funding for the research on tadpoles came from the ISU School of Graduate Studies and the Indiana Academy of Sciences.