University of Cincinnati scientists have literally drilled down through the teeth of mammoths and mastodons to discover their habits in what’s believed to be the first study of its kind in the region.
UC paleoecologist Brooke Crowley borrowed some mammoth and mastodon teeth from the Museum Center with hopes of finding out where they lived and what they ate. The specimens, very small amounts of white powder from the teeth, were eventually sent to the University of Illinois for testing.
- Samples were dissolved in nitric acid and the strontium was removed
- The strontium was released from the strontium specific resin and put back into clean nitric acid and diluted
- It was analyzed by a mass spectrometer
- The liquid was put through a plasma
- The result was an ionized strontium
Crowley and her assistant, now UC graduate Eric Baumann, studied the ratios of carbon, oxygen and strontium isotopes. Each element tells a different story.
- Strontium isotopes can tie the giant animals to a location
- Carbon provides insight into an animal's diet
- Oxygen relates to the overall climatic conditions
It turns out these mammoths and mastodons stayed right around Cincinnati despite what was previously thought about their migration patterns. Crowley says the tooth tests indicated the mammoths ate more grasses and mastodons favored leaves and shrubs.
Crowley says, “Really all I can do is speculate, but I think this area was at the very edge of the last ice sheet at the last glacial maximus. There was a big ice sheet that covered a lot of North America and we were at the very southern edge of that.”
Even though the samples were small, the teeth weren’t. People are still finding them in their yards. Baumann had the fun job of using the dental drill to get the samples.
“The biggest tooth could fit in my arms," Baumann says, "I could probably bear hug it. That was probably the biggest tooth and we had other ones, maybe as big as my hand.”
He drilled 12 teeth from four mastodons and eight mammoths.
Crowley says mammoths and mastodons migrated in other parts of the country to get a particular nutrient at a certain time of year but if they have the food they need they don’t migrate. There have only been a handful of studies utilizing strontium isotopes. One in Florida showed mastodons moved up and down the east coast. A New Mexico study found mammoths there liked the area and stayed put also.
So how can this research help endangered elephants? Crowley says already some work has been done on strontium for living elephants to identify their herd. This was done to reduce poached ivory.
She notes, “Africa is a very different place in terms of geology than North America, more complicated there but my hope is there, by understanding the ecology of these animals prior to a lot of human disturbance, living in a natural setting we can understand a little bit more about their natural mobility, their natural needs.”
Perhaps studying the isotopes in tusks is next. Crowley says, "We don’t have that ability with a single tooth, but we do with a tusk that’s a new direction, thinking about bigger patterns, overall patterns, data mining and working with some other collaborators.”
Crowley and Baumann’s research was just published in Boreas, an international academic research journal.