About Cave Bears

I've always been fascinated by archaeology.  This article is about cave bears.

Fate of the Cave Bear

Herv?? Bocherens says his colleagues find his research methods a little "crude." He dissolves 30,000-year-old animal bones in hydrochloric acid strong enough to burn through metal, soaks the bone solution in lye, cooks it at about 200 degrees Fahrenheit and freeze-dries it until what's left is a speck of powder weighing less than one one-hundredth of an ounce. The method may be harsh, but the yield is precious-the chemical biography of a cave bear.


Bocherens, an evolutionary biologist at the University
of T??bingen, Germany, is in the vanguard of research on
the bear, a European species that died out 25,000 years
ago. People have been excavating cave bear remains for
hundreds of years-in the Middle Ages, the massive skulls
were attributed to dragons-but the past decade has seen
a burst of discoveries about how the bears lived and why
they went extinct. An abundance of bear bones has been
found from Spain to Romania in caves where the animals
once hibernated. "Caves are good places to preserve
bones, and cave bears had the good sense to die there,"
Bocherens says.

Along with mammoths, lions and woolly rhinos, cave bears
(Ursus spelaeus) were once among Europe's most
impressive creatures. Males weighed up to 1,500 pounds,
50 percent more than the largest modern grizzlies. Cave
bears had wider heads than today's bears, and powerful
shoulders and forelimbs.

Prehistoric humans painted images of the animals on cave
walls and carved their likeness in fragments of mammoth
tusk. But the relationship between humans and cave bears
has been mysterious. Were humans prey for the bears, or
predators? Were bears objects of worship or fear?

Cave bears evolved in Europe more than 100,000 years
ago. Initially they shared the continent with
Neanderthals. For a time, archaeologists thought
Neanderthals worshiped the bears, or even shared caves
with them. The idea was popularized by Jean Auel's 1980
novel, The Clan of the Cave Bear, but has since been
rejected by researchers.

Modern humans arrived in Europe about 40,000 years ago
and were soon aware of the bears. The walls of France's
Chauvet cave, occupied 32,000 years ago, are painted
with lions, hyenas and bears-perhaps the oldest
paintings in the world.

The artists weren't the cave's only occupants: the floor
is covered with 150 cave bear skeletons, and its soft
clay still holds paw prints as well as indentations
where bears apparently slept. Most dramatically, a cave
bear skull was perched on a stone slab in the center of
one chamber, placed deliberately by some long-gone cave
inhabitant with opposable thumbs. "There's no way to
tell if it was just curiosity that made someone put a
skull on the rock or if it had religious significance,"
says Bocherens.

Another discovery, hundreds of miles to the east of
Chauvet, would shed light on the relationship between
cave bears and humans.

The Swabian Jura is a limestone plateau in southwestern
Germany that is riddled with caves. A short walk from
the village of Schelklingen takes visitors to the foot
of a limestone cliff in the Ach Valley. A steel gate
guards the Hohle Fels cave from vandals and curiosity-
seekers. Inside, the sound of dripping water competes
with the quiet conversation of a half-dozen
archaeologists.

Floodlights in the cave's main chamber illuminate the
ceiling, vaulted like a cathedral above 5,000 square
feet of floor space. Long ago, as shown by the bones and
tools that archaeologists have found, cave bears and
human beings sought shelter here from winter weather.

In 2000, University of T??bingen paleobiologist Susanne
M??nzel unearthed a bear vertebra with a tiny triangular
piece of flint embedded in it. The stone was likely a
broken spear point, hard evidence of a successful bear
hunt 29,000 years ago.

M??nzel also found bear bones that had clearly been
scratched and scraped by stone tools. Cut marks on
skulls and leg bones showed that the bears had been
skinned and their flesh cut away. "There must have been
cave bear hunting, otherwise you wouldn't find meat cut
off the bone," she says. Many of the bones were from
baby bears, perhaps caught while hibernating.

Cave bears disappeared not long after humans spread
throughout Europe. Could hunting have led to the bears'
extinction??That's not likely, according to Washington
University at St. Louis anthropologist Erik Trinkaus.
"People living in the late Pleistocene weren't stupid,"
he says. "They spent an awful lot of time avoiding being
eaten, and one of the ways to do that is to stay away
from big bears." If hunting was an isolated event, as he
argues, there must be another reason the bears died out.

Herv?? Bocherens' test tubes may hold the clues. Running
his white powder through a mass spectrometer, he
identifies different isotopes, or chemical forms, of
elements such as carbon and nitrogen that reflect what
the bears were eating and how quickly they grew. After
studying hundreds of bones from dozens of sites in
Europe, Bocherens has found that cave bears mainly ate
plants.

That would have made the bears particularly vulnerable
to the last ice age, which began around 30,000 years
ago. The prolonged cold period shortened or eliminated
growing seasons and changed the distributions of plant
species across Europe. Cave bears began to move from
their old territories, according to a DNA analysis led
by researchers at the Max Planck Institute in Leipzig of
teeth found near the Danube River. The cave bear
population there was relatively stable for perhaps
100,000 years, with the same genetic patterns showing up
generation after generation. But about 28,000 years ago,
newcomers with different DNA?patterns arrived-a possible
sign of hungry bears suddenly on the move.

But climate change can't be solely to blame for the
bears' extinction. According to the latest DNA study, a
Max?Planck Institute collaboration including Bocherens,
M??nzel and Trinkaus, cave bear populations began a long,
slow decline 50,000 years ago-well before the last ice
age began.

The new study does support a different explanation for
the cave bear's demise. As cavemen-Neanderthals and then
a growing population of modern humans-moved into the
caves of Europe, cave bears had fewer safe places to
hibernate. An acute housing shortage may have been the
final blow for these magnificent beasts.

Andrew Curry writes frequently about archaeology and
history for Smithsonian.

___________________________________________