Mammoth and Mastodon Teeth Reveal These Massive Beasts Stayed at Home

For years, researchers thought that the ancient mammoths and mastodons that once roamed our planet were migratory. Yet it turns out that these beasts didn't travel nearly as much as scientists once believed. Instead, they much preferred to stay at home in Greater Cincinnati, becoming year-round residents.

Actually discovering this fact wasn't easy. The scientists turned to teeth in order to make the latest finding. They examined museum specimens of molars from four mastodons and eight mammoths. They drilled the teeth's surfaces and analyzed the stable carbon, oxygen and strontium isotopic signatures in the powdered enamel. While carbon provided insight into the animal's diet, oxygen related to overall climatic conditions and strontium showed how much an animal may have traveled at the time the tooth was forming.

"Strontium reflects the bedrock geology of a location," said Brooke Crowley, one of the researchers, in a news release. "So if a local animal grows its tooth and mineralizes it locally and dies locally, the strontium isotope ratio in its tooth will reflect the place where it lived and died. If an animal grows its tooth in one place and then moves elsewhere, the strontium in its tooth is going to reflect where it came from, not where it died."

In the end, the researchers found that mammoths ate more grasses and sedges than mastodons, which preferred leaves from trees or shrubs. In addition, neither of these species moved around a lot, revealing that they were far less migratory than previously thought. The two species also didn't inhabit the same localities and instead probably formed distinct populations.

"Based on our data, mammoths and mastodons seemed to have different diets and lived in different areas during their lives," said Eric Baumann, one of the researchers. "This is important because it allows us to understand how species in the past lived and interacted. And the past is the key to the present."

The findings are published in the journal Boreas.