Monthly Archives: June 2012

06/21/12

Using "Frog Juice" to Enhance Racehorse Performance

According to a recent New York Times article, frogs and horses have recently been linked in a bizarre—and illegal—way. Evidently a compound found in the secretions of the waxy monkey tree frog (Phyllomedusa sauvagei) is being used to enhance the performance of racehorses.

The waxy monkey tree frog is native to South America. While most frogs like cool and moist places, waxy monkey frogs live in the Chaco (dry prairie) of Argentina, Brazil, Bolivia, and Paraguay. They seal in moisture with a waxy substance secreted through their skin glands. Living in trees, they draw in their arms and legs and sleep in the sun. At night, they awaken and hunt when the air temperature and the rate of water loss are lower.

Waxy monkey tree frog. Photo by Mary Jo Rhodes (from exhibit Frogs: A Chorus of Colors, NYC)

The waxy substance in their skin contains a natural opioid called dermorphin, which is a more powerful painkiller than morphine. When injected into horses, it helps them run faster by dulling the pain from injuries. The substance has been found in more than 30 racehorses. According to the article, it is unclear where the substance is obtained, but it is probably artificially synthesized.

Abuse of horses seems to be rampant in horse racing. This use of “frog juice” is simply the most recent atrocity. In March, the New York Times ran another article titled “Mangled Horses, Maimed Jockeys.“

And, of course, this isn’t good news for the waxy monkey tree frog either.
06/11/12

Remarkable Frog Dads of Papua New Guinea

This is an updated repost of a Father’s Day post from 2009.

Most animal dads aren’t too involved with their offspring (human dads, excepted of course). But two species of frogs, Liophryne schlaginhaufeni and Sphenophryne cornuta, in the microhylid frog family are devoted dads, and in fact, carry their their brood of up to 25 froglets piggyback style through the rain forest of Papua New Guinea. The frogs were discovered by evolutionary biologist David Bickford.

While most frogs start their lives as tadpoles, these frogs undergo “direct development.” They bypass the tadpole stage and go straight from larvae to miniature versions of adults while still inside the egg. This is an adaptation that allows the frog to reproduce in regions without bodies of water nearby.

After the mother frog lays the eggs, she hops off while Dad watches over the clutch, warding off predators, and keeping the eggs moist for about a month.

copyright David Bickford

copyright David Bickford

After the froglets hatch from the eggs, they hop on Dad’s back. He carries them by night through the leaf litter in the rain forest. The froglets have a free ride until they grow up a bit and can live independently (hmmm…sounds familiar).

This is an updated repost of a Father’s Day post from 2009.