When the first complete skin of a duckbill
platypus arrived at the British Museum in 1798, the curators thought it a hoax.
Thick fur, webbed forefeet
and a ducklike bill? Too bizarre.
Even after recognizing the platypus as a new species,
taxonomists debated its proper place in the animal hierarchy.
Found only in Australia, it lays eggs like a reptile yet has
milk glands like a mammal, swims like a duck but has the fur of a beaver.
Ornithorhynchus anatinus was finally assigned to the
monotreme order of mammals, but it has never stopped bemusing zoologists.
Now, scientists report that the platypus is plugged in: it
can sense electrical fields, the first higher vertebrate found to have that
When a platypus dives underwater, a flap of skin covers its eyes and ears and valves shut off
its nostrils, leaving only the bill to locate food.
Biologists had thought the bill was purely tactile, feeling the currents stirred up by moving
Finally, when the researchers switched on an electrical field
behind a hollow brick, the animals turned over the brick, as if
searching for food, more than twice as often as they did when the
field was switched off.
By stimulating the platypus's bill with electrodes and simultaneously monitoring its brain for
activity, the researchers established that it is indeed the bill that senses electric fields.