The recent discovery of a fossilized tooth of an ancient giant sloth is helping scientists understand the environment 27,000 years ago and might help explain the extinction of megafauna in America.
The tooth was unearthed by divers in 2014 while in search for ancient Maya artifacts in Cara Blanca, Belize. Though partially fossilized, the tooth still has unaltered tissue that allowed for stable carbon and oxygen isotope analysis.
From the fossilized tooth, scientists were able to figure out what the sloth ate in the last year of its life, which therefore revealed information about the local climate and environment in the region thousands of years ago.
“We began our study with the hopes of gaining a better understanding of the landscape within which large mammals went extinct and humans emerged in central Belize,” said Jean T. Larmon, a graduate student at the University of Illinois, who led the study. “In the process, we discovered which part of the tooth had best maintained its integrity for analysis. And we refined methods for studying similar specimens in the future.”
The analysis revealed that the giant sloth, which grew to about 4 meters tall, lived through a dry season that lasted for seven months. The researchers also discovered that the creature lived in savanna and consumed a variety of plants that changed along with the seasons.
Their findings, Larmon explained, adds evidence to the idea that the giant sloths had a diverse diet and adapted readily to the climate. This explains why they were so widespread and lasted for as long as they did.
University of Illinois anthropology professor Lisa Lucero, who also led the study, said that the secrets uncovered from the fossilized tooth add evidence to the idea that many factors, in addition to the changing climate, contributed to the extinction of megafaunas, including the giant sloth, from the Americas 14,000 to 10,000 years ago.
“One of those potential factors is the arrival of humans on the scene 12,000 to 13,000 years ago,” she stated.
The study titled “A year in the life of a giant sloth during the Last Glacial Maximum in Belize” appears in Science Advances.