Five hundred million years ago, animal life appears to have burst out in glorious diversity, taking new shapes, sizes and forms in an event picturesquely known as the Cambrian explosion.

But the proof — a plethora of beautifully, intricately preserved fossils extracted from the Burgess Shale, a geological formation in Canada — has long been paradoxical. The fossils were once buried deep in the Earth's crust, exposed to temperatures exceeding 600 degrees Fahrenheit before being thrust up by tectonic forces. Why weren't they destroyed?

Researchers at the universities of Cambridge and Leicester and the British Geological Survey think they've found an answer: They suggest that as the delicate organic tissues of long-gone animals were heated, they were transformed into new minerals, preserving minute biological details like gills, guts and eyes.

"This provides a whole new theory for how fossils form," said Alex Page, one of the authors of a paper to be published in the journal Geology. "The deep heating may not have cremated them, but it certainly left them stone baked."

VERBATIM

I have never seen this kind of an increase in the number of applications with eggs, sperm donors or surrogates.

— Cathy Ruberto, owner of a Florida fertility clinic, attributing a rise in would-be donors to economic hard times

BRAIN SWEAT

In forensics labs, which blood cells are used for DNA analysis?

a) platelets

b) red blood cells

c) white blood cells

d) all of the above

BRAIN SWEAT ANSWER

C. Only white blood cells contain DNA.

PRIME NUMBERS

36,000 — Estimated number of Americans who die each winter from the flu or flu-linked causes

30,000 — Number who are age 65 or older

5 — Percentage of annual winter deaths for that age group attributed to the flu

70 — Percentage of Americans 65 and older who receive annual flu vaccinations

1 — Estimated lives saved per 200 flu vaccinations

Sources: Centers for Disease Control and Prevention; Lone Simonsen, George Washington University

"TRUE FACTS"

The moon weighs 81,000 trillion tons.

ELECTRON INK

GWAP

gwap.com

Developed by researchers at Carnegie Mellon University, this website allows you to play computer games that help researchers train and improve computer vision and artificial intelligence systems. It's smart fun.

QUIRKS OF NATURE

Researchers in Colombia have unearthed fossils of what could be the largest snake of all time, a relative of today's boa constrictor. The remains indicate the snake was more than 42 feet in length. The longest known modern-day snake is the reticulated python, which stretches out to a still-whopping 32.8 feet. The smallest known snake species is the recently discovered Leptotyphlops carlae, a kind of "threadsnake." It measures just 3.9 inches in length.

THERE'S A WORD FOR THAT

"Virtual water" refers to water used to grow produce or raise livestock that is then exported. For example, the United Kingdom imports 1,417 million cubic meters of virtual water each year from Spain, mostly in the shape of fruit and vegetables.

POETRY FOR SCIENTISTS

Fermi called the small bugger neutrino

After maybe a little much vino.

I hate to be crass,

But whatever its mass,

It's still way too small to be seen-o.

— Daniel Koon

To find out more about Scott LaFee and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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