Evidence
that suggests that modern humans lived at the same time as Neanderthals has
been contentious in archaeological circles for many years. A reevaluation of
artifacts from a cave in France, however, has reignited the debate over whether
the two species coexisted some 40,000 years ago.
New research on Neanderthal and human
artifacts excavated from this French cave is indicating that the two groups
lived here in successive generations, supporting the idea that Neanderthals
and humans coexisted. Image courtesy of Brad Gravina.
Archaeological evidence suggests that the Châtelperronians, the last Neanderthals
living in western Europe, disappeared around 35,000 to 34,000 years before present
(as figured through radiocarbon dating), says Jean-Jacques Hublin, director
of the human evolution department at Max Planck Institute for Evolutionary Anthropology
in Germany. The Aurignacians, the first anatomically modern humans, appeared
in France around 39,000 years before present, and brought with them new technologies,
such as tools and ornaments, which were not seen in the 200,000-year record
of Neanderthal cultures, Hublin says.
In the early 1950s, archaeologist Henri Delporte excavated the Grotte des Fées
cave in central France and recorded a sequence of archaeological levels that
extended 2.5 meters deep. Four distinct layers contained more than 750 artifacts
from the Châtelperronian Neanderthals, underlain by artifacts of an older
Neanderthal culture. In between the lowermost and upper three Châtelperronian
layers is a layer that looked different, says Paul Mellars, an archaeologist
at the University of Cambridge in the United Kingdom, and co-author of a paper
in Nature, published online on Aug. 31. That layer contained Aurignacian
tools and artifacts such as jewelry and reshaped blades made from a different,
nonlocal type of stone.
Delporte recorded this anomaly, but did not press the issue when he published
on his find because “the idea of a Neanderthal-human overlap would have
been considered heretical at the time,” Mellars says. So instead, the bones
and artifacts were cataloged and tucked away in a French museum for 50 years,
until Cambridge graduate student Brad Gravina found them this year.
As radiocarbon dating was just a budding technology and unproven when Delporte
published, the bones and artifacts had never been dated. Gravina and Mellars
brought the remains to England, where they ran accelerated mass spectrometry
radiocarbon dating analyses. The dates were conclusive, Mellars says: Châtelperronians
lived in the cave around 40,000 years before present, then left, and returned
again sometime after 36,000 years before present. In between, from 39,000 to
36,000 years before present, Aurignacians set up camp in the same cave.
“We cannot say how long any of these cultures occupied the site,”
Mellars cautions. “It could have been a few weeks to a few hundred years.
But we can demonstrate that these two cultures coexisted.”
Mellars and colleagues’ evidence that Châtelperronians and Aurignacians
overlapped is “strong and very important,” Hublin says. Other archaeological
sites in France and Spain have shown “interstratification” of Neanderthals
and humans, he says, but they were not as conclusive as this site, which “provides
a very consistent and solid series of dates that supports the same contemporaneity
and possible contacts.”
The researchers also correlated the occupant changes to climatic changes. Deep-sea
paleoclimate cores indicate that around 40,000 years before present, the climate
in Europe began growing colder. Neanderthals likely moved south to warmer climes
and humans moved in from colder areas to the east, around present-day Germany.
Then around 36,000 years before present, the climate began to warm, at which
time Mellars speculates that humans moved back north and east, and the Neanderthals
returned to central France. When the climate cooled again following a brief
warm period, it appears the Neanderthals were again driven out. Whether climate
played a part in their extinction, however, is unknown, Mellars says.
Additionally, to what extent the two species interacted — through trade,
war or sex — has remained, and will likely remain, highly contentious,
Mellars says. New evidence from the cave and other sites, however, continues
to provide examples of possible contact between the two groups, something Hublin
says will remain an important area of research.
Megan Sever
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