Photos © 1996, Minnesota Pollution Control Agency.
Deformed frogs in Minnesota!
The frogs found by Minnesota schoolchildren in 1995 looked like images from a digital photo retoucher run amok.
The frogs had too many legs. Or too few. Or had legs growing out of other legs. Scary stuff.
Nobody knows exactly why frogs have also begun showing up with such hideous deformities in Wisconsin, New York, Ontario and Quebec, but recent research points to something in the water.
In September, the Minnesota Pollution Control Agency and the National Institute of Environmental Health Sciences (NIEHS) released a study showing that pond water taken from areas with the worst deformities killed tadpoles or caused deformities as the frogs matured.
Furthermore, when the scientists diluted the pond water with pure water, the deformities became rarer. Since local well water also caused the same deformities, the Minnesota agency has offered bottled drinking water to nearby residents.
Although there's no word yet on which chemical may be to blame in the water, hormone-disrupting chemicals are suspected, since they are known to cause birth defects and kill young. It's also possible that some natural toxin or pathogen may be doing the damage.
Taking place against a backdrop of the worldwide decline in amphibians, the deformities could signal a dangerous imbalance, and might be something that affects people, not just wildlife. Says Dr. George Lucier, director of the NIEHS environmental toxicology program, "We know that something in the water, including groundwater, is extraordinarily potent in malforming frogs. We now need to determine if people are at risk. The causative agent or agents could be chemical contaminants or natural products such as pond plants or algae."
And before you get totally convinced that something in the water is causing the deformities, know that some scientists still suspect that parasites and UV light are at least partly responsible (see Deformed Frogs Leap Into Spotlight..., Jocelyn Kaiser, Science, 19 December 1997).
Fantastic flying frogs found!
'Twas back in 1997 that a group of British, Dutch and Brazilian technologists put a frog inside the core of a strong magnet and switched it on. Then they stood back and gaped as the little acrobat hovered in mid-air.
Why can frogs float? Because while only a few materials like iron are magnetic (attracted by magnets) many are "diamagnetic." Diamagnetic materials are inherent contrarians: they produce a weak magnetic field that's opposite to the one surrounding them. This field, being opposite, opposes the stronger field and this pushing causes the levitation.
Diamagnetism also explains why pieces of a superconductor can "levitate"above magnets. Since frogs have much weaker diamagnetism, their flights require a much stronger magnet.
And the flying frog? It scurried back to its home in the biology lab, seemingly unharmed by the experience. Here's hoping the little amphib took some snapshots from on high (see Floating Frogs, Science News, 12/6/97, p. 362-3).
The Why Files is not quite finished with this round-up of oddball science research.
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