(ALBUQUERQUE, N.M.) -- Plenty of crazy things can happen at bachelor parties, but celebrants in New Mexico had the sobering discovery of a prehistoric stegomastodon skull that is estimated to be 3 million years old.
Antonia Gradillas and his buddies celebrating a pal's upcoming wedding were hiking around Elephant Butte Lake State Park about 150 miles outside of Albuquerque, N.M., on Monday.
"As we were walking we saw a bone sticking out about one or two inches from the ground," Gradillas told ABC News.
Gradillas, 31, and his friends started digging and the skull began to surface. Gradillas realized this could be a major discovery, and he called a friend who works at a museum who directed him to Gary Morgan, a paleontologist with the New Mexico Museum of Natural History and Science.
After getting Gradillas' pictures of the skull, Morgan rushed the scene with his crew the very next day and told Gradillas that this could be a stegomastodon, a prehistoric animal that has been buried for about 3 million years.
Morgan explained that this prehistoric animal resembled modern elephants, but had a more squat build. He estimated that the creature uncovered by Gradillas likely stood about 9 feet tall, weighed more than six tons and was about 50 years old when it died.
"This mastodon was living, drinking, feeding alongside the ancient Rio Grande 3 million years ago," Morgan told ABC affiliate KRQE.
There is no way to tell how the creature died or its gender, Morgan said.
So far, museum crews have only found a skull.
"As we've dug around we haven't seen any other bones, so all the limb bones seem to be missing," Morgan said.
He said the skeleton could be one of the best preserved stegomastodon skulls in the U.S.
The skull was found sitting upside down. Crews spent Thursday covering it in protective newsprint, burlap, and plaster and preparing to load it on a truck. The skull will be hauled away to the New Mexico Museum of Natural History and Science.
The extraction process still gives Morgan "butterflies" after more than 20 years of experience. Fossils are fragile, despite their robust appearance.
Gradillas also got a thrill from his discovery.
"This is the coolest thing ever," Gradillas said. "Some people with Ph.D.s in this field might not even have this kind of opportunity. We were so lucky."
Gradillas said he was very impressed that the museum responded to his email so quickly.
"After Gary explained to me the details of the skull, I was just so impressed," Gradillas said. "It was so cool to see someone so passionate about what they do."
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