The spark that lit the flame under evolution’s gluteus maximus, quite literally, may have recently been found in a cave in modern-day Spain.
Paleontologist Michael Walker of the University of Murcia in Spain and his colleagues found the oldest evidence of fire making in Europe, supporting proposals that members of the human genus, Homo, regularly ignited fires starting at least 1 million years ago.
Archaeologist John Gowlett of the University of Liverpool in England said if the age estimate for the Spain find hold up, the new report adds to a “surprising number” of sites from deep in the Stone Age that retain evidence of small, intentionally lit fires.
Excavations conducted since 2011 at the Spanish cave, Cueva Negra del Estrecho del Río Quípar, have uncovered more than 165 stones and stone artifacts that had been heated, as well as about 2,300 animal-bone fragments displaying signs of heating and charring.
Microscopic and chemical analyses indicate that these finds had been heated to between 400° and 600° Celsius, consistent with having been burned in a fire.
Walker’s group doubts that sparks from a brush fire near the cave’s entrance could have triggered fires 5 to 7 meters inside the cave.
Furthermore, geologic evidence suggests that around 800,000 years ago, the cave bordered a river and a swamp.
As at other sites with signs of ancient fire making, early man at Cueva Negra left behind a range of stone tools signaling advanced technical skills, Walker says. Those savvy toolmakers must have known how to select wood or stone suitable for striking sparks onto small piles of tinder, he proposes.
Other researchers suspect Cueva Negra’s artifacts aren’t as old as reported.
A team led by biological anthropologist Juan Manuel Jiménez-Arenas of the University of Granada in Spain says it’s hard to say where the finds originally lay relative to several reversals of Earth’s magnetic field preserved in the cave’s layers.
A Homo species made tools there no more than about 600,000 years ago, the upper age limit in Europe for the types of stone artifacts found at Cueva Negra, Jiménez-Arenas’ group concluded in 2011 in the Journal of Archaeological Science.
Walker’s team says fossils of extinct animals excavated along with the stone tools support the older age for fire making in the cave. But even at 600,000 years old, the artifacts would still predate other evidence of controlled fire in Europe.