In the dry desert of New Mexico, a 10-year-old boy stumbled and fell. As he looked around, he found he’d made a startling discovery: a 1.2 million-year-old fossil. The remains turned out to be those of a large herbivore known as a stegomastodon, which eventually went extinct some 28,000 years ago.
“I was running farther up and I tripped on part of the tusk,” said 10-year-old Jude Sparks, who was walking apart from his family as he and his brother tested out their walkie-talkies. “My face landed next to the bottom jaw. I looked further up and there was another tusk.”
At first, Jude’s brother thought that the remains he’d found were those of a rotten cow, although it soon became clear that this obviously was not the case. After contacting Professor Peter Houde at New Mexico State University, they recovered an entire skull, and further excavation of the site revealed even more delicate fossils hidden beneath the surface.
It took months to get permission to finally uncover the entire fossil, and even then, the process was time-consuming and delicate work. The skull is estimated to weigh about a tonne, but that hides the fact that it is also incredibly fragile and “eggshell thin” in some places. “When the sediments are removed from the sides of them, they start to fall apart immediately and literally fall into tiny, tiny bits,” explained Houde. To counter this, the fossil was strengthened with specific chemicals during the dig.
While stumbling across a stegomastodon fossil in New Mexico is considered a pretty rare event, it is not actually the first time that it has happened. In 2014, a bachelor party also came across an almost complete fossil of the beast, which ended up being collected by the New Mexico Natural History Museum. Even so, only a few hundred stegomastodon fossils have ever been found globally, and no one is quite sure why they should be so rare.
The stegomastodon belonged to a group known as gomphotheres. This collection of bizarre animals were distant cousins to the more well-known mammoths and modern elephants. The stegomastodon is thought to have been somewhat of an oddity even among its own kind, as while many gomphotheres had four tusks protruding from their heads, the stegomastodons looked far more like modern elephants with only two.
“A stegomastodon would look to any of us like an elephant,” said Houde. “For the several types of elephants that we have in the area, this is probably one of the more common of them. But they’re still very rare. This may be only the second complete skull found in New Mexico.”