Just past mile marker eighteen on the bypass Shane Tucker, Highway Salvage Paleontologist with the University of Nebraska State Museum Lincoln, has unearthed a six to eight million-year-old tortoise shell.
Tucker's job is an interesting one, as the Nebraska Roads Department builds new roads he follows along and looks for possible fossils in the earth. Once a fossil is found, depending on the size and whether or not it is collectable, Tucker will dig it up and have it taken to the Nebraska State Museum.
Over the years working with the roads Department, Tucker has found some very interesting fossils. Evidence of Western Nebraska once being home to antelope, camels, short rhinos, three toed horses, bone crushing dogs, elephants and several other interesting creatures has been found.
"Some of the species we have found suggest that the climate here was very different millions of years ago. A lot of the animals suggest warmer temperatures," Tucker said.
In 2010 the tortoise shell in question was found, slightly tipped to the side, it lost a bit of the top of the shell but other than that remained quite in tact. However, due to other pressing projects at the time, Tucker was unable to get back to the shell until recently.
"It was uncovered about a half a foot and then left and due to the freezing weather there are some cracks in the shell that would not have been there otherwise. But I came back and started really unearthing the rest of it," Tucker said.
The tortoise, of course being a cold blooded animal would have needed warmer temperatures in order to survive. A fact that allows the thought that Western Nebraska at one time had a much warmer climate, thrive.
The size of these tortoises meant that that couldn't pull their heads and feet into their shell so they have special bones that covered the tops of their heads and legs, which are visible in the fossil. The size and inability to pull in it's head and legs mean this tortoise was not one to hibernate, also lending to the idea of warmer temperatures in the past.
The process for unearthing the rest of the tortoise shell involves digging below it and covering it in plaster to protect it.
"I'll cover it in plaster covered linen strips and then once that dries and I have it dug up around it we'll have a crane lift it out and load it onto a flat bed. Then we'll take it back to the museum and check it out more extensively, figure out a closer age of the fossil," Tucker said.
Tucker will not be using carbon dating to discover the age of the tortoise shell. Since carbon dating can really only be relied on for dating things back about 50,000 years, it would not work on the tortoise shell that is thought to be several million years old.
"We will have to analyze the layers of volcanic ash in the ground in order to determine the shell's age. It won't be spot on accurate, but it should get us within a million years," Tucker said.
While Tucker finds several fossils because of the roads department unearthing them, he also says that he receives some calls from people who find them while hunting, or working their land.
"Usually we can go out and take a look to determine how collectable it is and assess the situation as to whether or not we are able to dig it. We had an elephant fossil found in Potter, but it was in rock and almost impossible to dig. so we had to leave it," Tucker said.
Tucker had bones from several animals with him, some large and some very small. The interesting thing being their variety.
"It's really interesting finding everything and getting to see what Nebraska might have been like at a different time," Tucker said.
One of the fossils found was that of a rhinoceros. However, unlike modern rhinos, the rhino the fossil was from would have been much shorter.
"Imagine a rhino with more of a hippo build. Short and about ten feet in circumference. That's what that would have looked like," Tucker said.
The fossils that have been found by Tucker and others can be found at the Nebraska State Museum. at the park.