Mini treadmill helps scientists understand mysteries of amphibian mating
Date: December 20, 2016
Source: Ohio State University
Most salamanders are homebodies when it comes to mating. But some of the beasts hit the road, traversing miles of rugged terrain unfit for an amphibian in pursuit of a partner from a far-away wetland.
And when those adventurers leave home, they travel an average of six miles -- and as far as almost nine miles -- to new breeding sites, a new study has found.
That's a long haul on four squatty legs.
The scientists who unlocked this evolutionarily important information got there by cross-referencing genetic details from salamanders in various Ohio wetlands with the distance the animals would walk on a treadmill before tiring out.
The research, published online this month in the journal Functional Ecology, is the work of scientists at The Ohio State University who want to better understand how and where salamanders procreate and how that fits into work to preserve the animals, including land conservation efforts.
It is a mystery what prompts a salamander to cross rocks, fields, streams and roads to mate and, in the process, mix up the genetics of another salamander outpost far from home, said lead author Robert Denton.
"It has to be incredibly intimidating for these tiny salamanders. They could get eaten by a crow or a raccoon. They could dry out," said Denton, a presidential research fellow in Ohio State's Department of Evolution, Ecology and Organismal Biology.
"This is the first study to connect physiological factors -- particularly how fast they get tired of walking -- with genetics showing animal movement in the field."
Understanding these connections is critical to predicting how environmental and other changes can harm species, Denton said. Dispersal -- leaving the birthplace for a new habitat -- is a key element of keeping a species genetically healthy, he said.
Animal travel for breeding is a complex area of research, he said. There are a lot of factors to consider, including how they decide to move, why only certain animals hit the road and how they actually complete the journey -- in a series of shorter trips or all at once, for instance.