n addition to his lab work, Professor Hayes has traveled all over the world, from Africa to Southeast Asia, and Japan to Costa Rica, to study frogs in their natural habitat. He says both the lab and field are critical to his research. "For example, we're interested in stress and how that induces metamorphosis," he says. "In the lab, we can study what hormones are involved, what genes they turn on and off. You can't do that in the field. But in the lab you can't see a pond drying up, with all the tadpoles trying to developmentally escape death by metamorphosing faster into frogs. You can't understand the evolutionary significance of these changes without seeing them in the wild."
Hayes' primary interests are in understanding amphibian evolution and basic biology, but his research also has implications for conservation and even cancer biology. In addition to counting, cataloging, and photographing wild frogs in the field, Hayes and his students collect specimens to bring back to the lab and start a breeding stock. "Because these animals are under so much environmental pressure," says Hayes, "we limit what we collect. I won't work with an animal that we can't raise in the lab."
Most of the year he's surrounded by tens of thousands of hand-reared frogs in his lab, but Professor Hayes is all too aware of the perils that frogs face in the wild, including pollution, habitat destruction, and human predation. In many cultures throughout the world, including in the U.S., Europe, and Southeast Asia, frogs are food. Humans also have significant impact on frog habitat as high-level consumers of natural resources.
"When I was visiting
a market in Asia recently," he says, "I realized what incredible predators
we are. In one day in one city, I must have seen thousands of live skates,
and tens of thousands of shrimp and little fish in barrels. It makes
you realize what pressure we put on the environment. We do it here too,
but in the U.S. ours is all packaged as meat. We grow a lot of our food,
but that also puts a lot of pressure on the land. We're huge consumers."
© 1999, The Exploratorium