When the first stuffed specimens of the platypus arrived in Europe at the end of the 18th century, scientists thought they were looking at a taxidermic hoax: a beaver's body with a duck's bill and webbed feet.

The platypus is one of nature's oddest looking creatures. Now it turns out it's odd on the inside as well. Researchers at Oxford University in England have just finished mapping the platypus genome. Its genes are pretty mixed up too.

Indeed, the Australian native is a genetic potpourri: part bird, part reptile, part lactating mammal. It's classified as a mammal because it produces milk and is covered by hair. It defends itself with a foot spur containing snakelike venom. It has webbed feet, a flat bill similar to a duck's and reproductive gene sequences similar to those of birds.

“It is much more of a melange than anyone expected,” said Ewan Birney, who led the genome project.

Platypuses display another unusual trait called electroreception. Employing sensitive receptors inside its bill, a swimming platypus can detect the electric fields generated by moving prey such as shrimp, crayfish, worms and insect larvae. The ability is very useful in dark, murky waters where the platypus typically hunts.

So add another animal to the platypus' menagerie of traits: Some sharks also employ electroreception to hunt.

VERBATIM

The cloning of humans is on most of the lists of things to worry about from science, along with behavior control, genetic engineering, transplanted heads, computer poetry and the unrestrained growth of plastic flowers.

– PHYSICIAN AND ESSAYIST LEWIS THOMAS (1913-1993)

BRAIN SWEAT

Select the two phrases of the following five that are equivalent:

a. 14 square yards

b. 14 yards square

c. 127 square feet

d. 196 square yards

e. 206 yards squared

PRIME NUMBERS

29,500 – Number of artificial reservoirs in the world

10,800 – Amount of water, in cubic kilometers, contained in these reservoirs (about twice the volume of Lake Michigan)

30 – Estimated rise, in millimeters, in sea level due to global warming that hasn't happened because of artificial reservoir construction in the past 50 years.

Sources: Scientific American; National Central University, Taiwan

ELECTRON INK

Cool science for curious kids

hhmi.org/coolscience/index.html

Adapted from five museum exhibits and supported by the Howard Hughes Medical Institute, this site is what the name says: a cool science place for curious kids. Interactive categories explore and explain why monkeys are like moose, why caterpillars don't look like butterflies, and what's all that strange stuff we breathe every day.

QUIRKS OF NATURE

The stalk of a mushroom supporting the cap is called a “stipe.”

JUST ASKING

Why do psychics ask you for your name?

BRAIN SWEAT ANSWER

Phrases b and d are equivalent. “Fourteen yards square” describes a square measuring 14 yards by 14 yards, or 196 square yards.

SURELY YOU'RE JOKING

A venerable Indian chief had three wives. The first wife slept on a bed made of cowhide. The second wife slept on a deerhide bed. The third wife slumbered on a bed of hippopotamus hide. In time, the first wife gave birth to a baby boy, the second to a baby girl, and the third wife had twins, a boy and a girl.

Looking at the results, the old chief declared: “This proves the mathematical theory of our long-gone forebears: The Squaw on the hippopotamus is equal to the sum of the squaws on the other two hides.”

POETRY FOR SCIENTISTS

Tell me why the stars do shine.

Tell me why the ivy twines.

Tell me what makes skies so blue.

And I'll tell you why I love you.

Nuclear fusion makes stars to shine.

Tropisms make the ivy twine.

Raleigh scattering make skies so blue.

Testicular hormones are why I love you.

– ISAAC ASIMOV (1920-1992)

THIS WEEK IN SCIENCE

This week in 1980, following a week-long series of earthquakes and smaller explosions of ash and smoke, the long-dormant Mount Saint Helens volcano in Washington state erupted, hurling ash 15,000 feet into the air and setting off mudslides and avalanches. Fifty-seven people were killed; 250 homes, 47 bridges, 15 miles of railways and 185 miles of highway were destroyed. The eruption was characterized as the equivalent of 27,000 atomic bombs. The resulting cloud of ash eventually circled the globe.