Frogs. They’re familiar and otherworldly, slimy and charming, the kind of odd liminal animal that spurs the imagination. Their voices range from the brute croak of the bullfrog to the fairy-sweet, bell-like chorus of the spring peeper. Our complex relationship with frogs shows up even in our childhood in the deeper meanings of the well-known fairy tale, The Frog Prince – ranging from a moral injunction on the rewards for living up to one’s promises, to a symbol of a young princess’ maturation from childhood to adulthood in the transformation of frog to prince on her pillow.
So the plight of frogs worldwide touches a special and symbolic chord. A deadly fungus, the amphibian chytrid, has led to as many as 30% of all frog species worldwide being threatened with extinction since it first appeared in 1993 – and hundreds are already extinct. What would our world, from the literary to the literal, be without frogs?
No one understands how to slow chytrid’s spread. But a study today in the journal PLOS ONE suggests we may have been studying the fungus too narrowly. Biologist Kevin Smith and his colleagues at the University of Washington St. Louis found that of all Missouri ponds expected to harbor the fungus, only a third actually had chytrid present. Frogs in the remaining ponds were healthy and chytrid free – even when the ponds had the right chemistry and water temperature for the fungus.
“Focusing only on amphibians to understand chytrid is like focusing only on people to understand Lyme disease,” says Smith. Just as deer, and in turn deer ticks, carry Lyme, other organisms besides frogs may serve as hosts for the chytrid. Without the presence of these animals or plants, Smith theorizes, the chytrid wouldn’t be able to survive long, and wouldn’t therefore infect nearby frogs. The study is a start in trying to take a wider, ecosystem-level view of the chytrid and its requirements for growth.
But it won’t, of course, allow us turn around and save the frogs. Biologists and frog enthusiasts are so worried that they’ve begun keeping frog exemplars in captivity – using networks of zoos and other institutions, such as the Amphibian Ark, to harbor rare living frogs until the chytrid can be more effectively battled.
The last known Rabbs fringe-limbed treefrog, for instance – collected early on in the chytrid epidemic along with others that have since died of natural causes – lives at the Atlanta Botanical Garden in a special enclosure. His handlers have nicknamed him Toughie, and say they try to touch him as little as possible. “It’s pretty nerve-wracking taking care of him,” says the Garden’s Mark Mandica.
I’ll take a new, healthy generation of Toughie tadpoles over a prince, honestly. What do I have to kiss, tell me, to achieve that miracle?
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This post is the first in a series of science tidbits, short cogitations on recent science findings that interest me and on why they do.