Anthropologists have found skeletons of at least 14 woolly mammoths that died after falling into traps built by humans 15,000 years ago.
The two pits were found in Tultepec, just north of Mexico City, Mexico’s National Institute of Anthropology and History said this week.
Researchers speculated that ancient hunters probably chased the giant animals into the pits, which are 1.70 meters deep and 25 meters in diameter (5½ feet by 82 feet).
There was some evidence that some of the mammals had been butchered.
Luis Cordoba, the head of the excavation team, said the discovery was key in studying the relationship between prehistoric hunting and gathering communities and the huge herbivores.
“There was little evidence before that hunters attacked mammoths. It was thought they frightened them into getting stuck in swamps and then waited for them to die,” he told reporters. “This is evidence of direct attacks on mammoths. In Tultepec we can see there was the intention to hunt and make use of the mammoths.”
Using a special type of radar, researchers have discovered the invisible footprints hiding since the end of the last ice age — and what lies beneath them.
The fossilised footprints reveal a wealth of information about how humans and animals moved and interacted with each other 12,000 years ago, according to the study published in the journal Scientific Reports.
“We never thought to look under footprints, but it turns out that the sediment itself has a memory that records the effects of the animal’s weight and momentum in a beautiful way,” said study lead author Thomas Urban from Cornell University in the US.
“It gives us a way to understand the biomechanics of extinct fauna that we never had before,” Urban said.
The researchers examined the footprints of humans, mammoths and giant sloths in the White Sands National Monument in New Mexico.
Using ground-penetrating radar (GPR), they were able to resolve 96 per cent of the human tracks in the area under investigation, as well as all of the larger vertebrate tracks.
“But there are bigger implications than just this case study,” Urban said.
“The technique could possibly be applied to many other fossilised footprint sites around the world, potentially including those of dinosaurs. We have already successfully tested the method more broadly at multiple locations within White Sands,” Urban added.
“While these ‘ghost’ footprints can become invisible for a short time after rain and when conditions are just right, now, using geophysics methods, they can be recorded, traced and investigated in 3D to reveal Pleistocene animal and human interactions, history and mechanics in genuinely exciting new ways,” said study co-author Sturt Manning.