SCIENCE LAB SPECIAL : MASTODON'S RESEARCH

 

Scientists piece together a mastodon's movements, along with his maladies. Its Tusks reveal a life of fighting.

Over 13,000 years ago, an American mastodon roamed what is today the American Midwest. Year after year, he returned to an area in northeast Indiana - believed to be a mating ground. It was there that he died in battle.

Where the mastodon spent his life and how he died were all recovered by studying chemical signatures recorded in his tusk, scientists reported this week in the Proceedings of the National Academy of Sciences.

Their techniques offer new insight into one of several ancient elephant relatives that roamed North America before going extinct.

Scientists studied the Buesching mastodon, named for the family farm where it was found in 1998, and now on display at the Indiana State Museum.

Also known as Fred, his tusks, like those of modern elephants, record an animal's entire life history and enable scientists to glean information from specific days, weeks or years. Thus, the scientists could specifically sample areas within its tusk from its adolescence and adulthood and determine how its migration changed over time.

This migratory detective work focused on strontium and oxygen isotopes in the tusks, Joshua Miller, a paleontologist from the University of Cincinnati and an author of the study, described strontium isotopes as leaving signals all over the landscape.

Strontium isotopes leach from rocks into surrounding soil and water. As plants absorb those nutrients, they incorporate ''those isotopic signatures,'' he explained.

Our hungry mastodon would come along and eat those plants,stamping the geographic fingerprint into his tusks.

Interpreting these geographical references and matching them with the landscape takes one more step : a map of strontium isotopes change across terrain.

The authors built upon the work of other scientists, including Brooke E. Crowley, also of Cincinnati and one of the study's co-authors, who has created such a map.

The World Students Society thanks author Jeanne Timmons.