The oldest elephant herd ever to exist may have been found by scientists from the United Arab Emirates. The researchers found fossilized footprints in an Arabian desert dating back over 6 million years.
The paleontologists' discovery of the oldest elephant herd, reported in scientific journal Biology Letters, shows at least 13 elephants – both adults and young calves – on an interrupted trail through mud of almost 853 feet (260 meters) long.
The elephant herd did not consist of the same elephants that we have today. The tracks, which are about 15 inches (40 centimeters) wide, were most likely made by the four-tusked Stegotetrabelodon syrticus – the elephant ancestor most likely to be in open country.
The footprints provide huge insights into the way older animals behaved.
"Basically, this is fossilized behavior," researcher Faysal Bibi, a vertebrate paleontologist at the Museum of Natural History in Berlin, told LiveScience. This is an absolutely unique site, a really rare opportunity in the fossil record that lets you see animal behavior in a way you couldn't otherwise do with bones or teeth."
The site, dubbed Mleisa 1, shows how elephants spent their time in groups and alone. While the herd's tracks move in a similar pattern and direction, one lone pair of tracks cuts across theirs. While the lone elephant's tracks were probably laid down afterwards, it is evidence that these animals functioned both together and alone.
It wasn't easy to come to that conclusion, however. The tracks cover the space of nine football fields, or about 12 acres. Scientists had to devise a unique way of viewing the prints to get the entire story.
"Once we saw it aerially, it became a much different and clearer story," researcher Brian Kraatz, of Western University of Health Sciences in Pomona, Calif., told LiveScience. "Seeing the whole site in one shot meant we could finally understand what was happening."
The discovery could contribute greatly to the way researchers understand social behavior among elephants in a way that was previously impossible.
"It is quite obvious to anyone, without any technical knowledge, that these are the footprints of very large animals," said scientist Andrew Hill of the University of Poitiers in France.
"To learn that they are over 6 million years old presents a visitor with the sensation of walking back in time."