Over the last several decades, amphibians around the world have
been disappearing. Dozens of species have vanished entirely; others
are simply becoming harder and harder to find.
In Yosemite National Park in California, three of the seven native
frog and toad species are gone, while the population of the remaining
four species is dropping. Ten frog species have disappeared from
Australia, including the Gastric brooding frog, which hasn't been
seen since 1982. In Monteverde, Costa Rica, golden toads which
once congregated by the hundreds haven't been seen since 1990.
Meanwhile, deformed frogs with missing or extra legs are turning
up all over the United States.
such as this, first discovered by school children in Minnesota,
are now commonly found in frogs throughout the U.S. [Click
for a larger image.] Photo of the courtesy Minnesota Pollution
to this National Public Radio report on the U.S.
government response to the world-wide phenomena of sick
and dying amphimbians, and its impact on humans. Originally
aired on NPR's "Morning Edition" of 5-19-98. [Need
may be several factors working to harm the world's amphibians.
Among these are climate changes, including global warming and
thinning of the ozone layer. Destruction of habitat is certainly
a problem; when rain forests get chopped down and marshes get
filled in, frogs are left with nowhere to go. Pollution is also
probably connected to the decline. Since frogs absorb water directly
through their skin, they're especially vulnerable to water pollutants
like pesticides and acid rain.
skin fungus may also be responsible. This fungus is believed to
slowly suffocate frogs by attacking the skin through which they
breathe. It has been detected in the bodies of dead and dying
frogs of various species from Panama to Australia. This type of
fungus doesn't usually attack frogs, a fact which leads some scientists
to think that the frogs are being weakened by other environmental
Frogs are considered "indicator species," because they are the
first to be affected by degradation of the environment. Their
dwindling numbers may be a warning to us that our planet is becoming
unlivable. No matter what's behind it, the disappearance of frogs
is cause for concern. With a combination of conservation and study,
we can help keep frogs hopping for another 190 million years.
red-eyed tree frog (Agalychnis
[Click for a larger image.] Photo by Amy
What have frogs done for you lately?Well, to begin with,
frogs eat insects that we consider pests. A dwarf puddle
frog can eat up to 100 mosquitoes in one night.
also provide us with food. Frog legs are popular fare throughout
Europe, as well as in the southern United States. (They're
said to taste a lot like chicken.)
frogs' internal anatomy is similar to that of higher animals,
they're often used in medical research, for example, to
test new drugs. Meanwhile, students learn about anatomy
by dissecting frogs, though computerized "virtual dissections"
are gaining popularity as a modern alternative.
skin is a pharmacological bonanza, containing all manner
of interesting compounds. Chemicals recently isolated from
the skin of a South American frog have led to the discovery
of a pain killer that is more powerful than morphine, yet
also less addictive.