Early 'Peking Man' was older, colder, study says

SETH BORENSTEIN, AP Science Writer

WASHINGTON – A famous early ancestor of humans was

able to thrive in glacial weather that would send icy

shivers up the spines of most modern people, new

research shows.

New dating techniques suggest the remains of so-called

Peking Man -- a batch of Homo erectus fossils found in

the 1920s -- are 200,000 years older than previously

calculated.

What's important about that date, about 770,000 years

ago, is that this was a glacial period on Earth, and Peking

Man was found in far northern China.

That suggests he was probably the oldest cold weather

inhabitant in human ancestry, said study co-author Darryl

Granger, an atmospheric scientist at Purdue University

whose research appears in Thursday's edition of the

journal Nature. The average yearly temperature at the

time in that part of China -- at Zhoukoudian near Beijing --

hovered around the freezing mark, but it was too dry for

an ice sheet, he said.

Think of living in a "dry windy cold" much like winters in

Calgary, Canada, without warm close-fitting clothes and

well-made buildings to keep you warm, he said. And these

inhabitants may not have even been able to warm up with

a fire whenever they wanted either.

"They may have been freezing their buns off," said Rick

Potts, a Smithsonian Institution human origins expert who

wasn't part of the research. The research also

demonstrates just how "wimpy" modern humans are, he

said.

This raises a fundamental question. How did Peking Man

survive the cold weather?

Potts raised three possibilities:

Fire. Early findings showed signs of a fire in Peking Man's

cave. But there has been debate about whether the fire

was accidental or controlled, and evidence doesn't point

conclusively either way.

Fur. There is no evidence that this human ancestor used

crude tools to make more form-fitting clothes. Loosely

worn animal fur is more likely.

Homo erectus had evolved to handle the cold.

It's that last part that is the most intriguing, Potts said.

Just like the more modern Neanderthal, Peking Man may

have had physiological changes that allowed more blood

to flow to his extremities, he said.

"People in general who live in colder climates tend to be

shorter and squatter," Potts said.

These aren't the oldest human ancestors in Asia, but it's

the time period and the northern locale that intrigues

experts.

The study authors were able to put Peking Man in colder

weather because of a new method of dating the cave

where the fossils were found. Many of the Peking man

specimens were mysteriously lost after World War II. So

Granger and his colleagues used quartz and other material

that was found buried with the fossils.

The usual methods for dating -- carbon-14 or uranium --

don't go back far enough time, so the scientists looked at

the ratio of aluminum to beryllium, which decay at different

rates to come up with the new dates, Granger said.

On the Net

Nature: http://www.nature.com/nature

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