Science

Ancient Fossil Record Shows What Life Of Giant Ground Sloth Was Like

Ancient Fossil Record Giant Ground Sloth
Quinn Dombrowski [CC BY-SA 2.0], via Wikimedia Commons
There’s not much information about what the life of the giant ground sloth looked like before its extinction. But, an ancient fossil record reveals that the colossal animal spent its last days hungry and thirsty, as the last glacial maximum sucked up all of Earth’s moisture and water in the polar ice caps.

A team of scientists studied the fossil records of the 13-foot animal found in central Belize. Unlike the jungle that we greet in the area today, Belize used to be arid some 27,000 years ago. Scientists believe that a sinkhole with steep walls where the fossils were uncovered was the last place where the animal was, drinking water. A group of divers found them accidentally while on an expedition of finding Mayan artifacts in the pool in Cara Blanca.

The tooth the scientists found in the ancient fossil record allowed scientists to perform stable carbon and oxygen isotope analysis which gave information about what the food was that the giant ground sloth ate in the last year of its life. Their findings were described in the journal Science Advances.

“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,” University of Illinois graduate student Jean T. Larmon, who led the research with U. of I. anthropology professors Lisa Lucero and Stanley Ambrose said in a statement. “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.”

This gave scientists just another clue that among many factors, climate change affected the fauna on the American continents, according to Lucero who also studies Mayas of central Belize. “One of those potential factors is the arrivals of humans on the scene 12,000 to 13,000 years ago,” she added.

Scientists performed the isotopic analysis that revealed that the giant sloth was quit adaptable, likely living through a long dry season which lasted about seven months. There appeared to also be two short rainy seasons during the year, according to the tooth analysis.

“This allowed us to trace monthly and seasonal changes in the sloth’s diet and climate for the first time, and also to select the best part of the tooth for reliable radiocarbon dating,” Ambrose said.

The analysis also revealed a lot about the habitat where the giant ground sloth lived based on its ancient fossil record. It revealed that instead of forested areas, the sloth lived in savanna, managing to find a lot of plants it could consume to survive, adapting between dry and wet climates. The plants it ate were different between the dry and wet seasons. However, with the last glacial maximum, it couldn’t easily find and consume water.

“We were able to see that this huge, social creature was able to adapt rather readily to the dry climate, shifting its subsistence to relying upon what was more available or palatable,” Larmon said.