Sex and the Suburban Transgender Frog

I guess you can call them transgender frogs.

A group of Yale ecologists have found a surprising number of male frogs around Connecticut with very distinct properties that make them different from other male frogs. These frogs are carrying eggs, and the Yale team told the Waterbury Republican American they can't seem to figure out why.

"Seeing rates of deformity that high has been enormously surprising," Yale researcher David Skelly told Republican American.

Skelly and his team collected frogs in 24 ponds in 10 different cities and towns along the Connecticut River Valley.  They found one in eight male frogs had developed both sperm and eggs in their reproductive systems, according to the paper. Skelly said that number rose to one in five in suburban areas, and dropped to near zero in for rested areas. 

"The fact that it's concentrated around ponds and people's backyards is also very surprising," Skelly told the paper. 

Skelly was appointed by the Environmental Protection Agency to a panel reviewing a student by a University of California-Berkeley professor on the herbicide atrazine. The study's author believed atrazine caused sexual deformities in frogs that came in contact with the chemical.

The findings of that study were gleaned from research done in a laboratory, something Skelly says doesn't always prove true.

"What was missing from this story at that point, and is still largely missing, is the outdoor context. Just because you see something in the lab doesn't mean it's going to play out that way in the world," he told the Republican American. "There's a zillion things that can happen between that and the world." 

Skelly's theory leans towards more common chemicals, other than atrazine. He believes pollutants in waste water, such as synthetic estrogen found in birth control pills could be a factor. If the drugs get into the waste water, and then leak into the ecosystem, it could be affecting the frogs, the paper reports. Though Skelly says that hasn't been proven yet either. 

Contact Us