Two Halves of Same Individual Sea Turtle Bone Found 160 Years Apart [VIDEO]

What started as an amateur fossil collector's search for shark teeth in a New Jersey streambed turned into a paleontological connection bridging more than a century and a half. A fossilized partial bone of a giant sea turtle discovered in 2012 was found to be the missing piece of a giant turtle bone placed in museum archives in 1849.

Hobbiest fossil hunter Gregory Harpel was searching for shark teeth in Monmouth County, NJ when he came across a puzzling rock-like object that turned out to be the most recent half of the fossil. The heavy object intrigued Harpel enough that he took it to the New Jersey State Museum for experts to examine.

The fossil came into the hands of Jason Schein, assistant curator of natural history at the New Jersey State Museum. Schein and his collaborators recognized the fossil as a humerus - the large upper arm bone - from a sea turtle. But the fossil was broken, only the distal end - the part nearest the elbow - remained. The scientists joked that the missing half could be in a museum somewhere - it did, after all, look strangely familiar.

The paleontologists attempted to identify and describe the fossil, but they needed to turn to other fossil collections for the analysis, so they took the specimen to the fossil collections at Drexel University's Academy of Natural Sciences in Philadelphia, Pa. Housed in Drexel's collection was a peculiar sea turtle humerus fragment, one that was broken at the proximal end, nearest to the shoulder - exactly what was missing from the newfound fossil.

"I didn't think there was any chance in the world they would actually fit," Schein said.

But they did.

Ted Daeschler, associate curator of vertebrate zoology at Drexel's Academy of Natural Sciences, said the moment the pieces came together was like a filling in a missing blank.

"As soon as those two halves came together, like puzzle pieces, you knew it," he said.

Both fossil specimens were determined to belong to the same individual sea turtle. The older of the two fossil specimens was documented in 1849 by 19th-century naturalist Louis Agassiz, whose description of the first bone went on to be the holotype, or the single type specimen, of the species Atlantochelys mortoni.

This discovery is not only a remarkable coincidence, but a revelation that defies conventional wisdom of how long fossils can withstand being exposed to the elements. A fossil unearthed and left exposed to the elements is generally not expected to last beyond a few years, or perhaps a decade. Yet this the newfound fossil had been exposed for at least as long as the original half of the humerus.

"Sure enough, you have two halves of the same bone, the same individual of this giant sea turtle," said Daeschler. "One half was collected at least 162 years before the other half."

With a complete bone, the paleontologists were able to create a more complete description of the ancient turtle, which lived during the Cretaceous Period, 70 to 75 million years ago. They've calculated the animal's overall size to be about 10 feet from tip to tail, making the ancient reptile one of the largest sea turtles ever known.

"The astounding confluence of events that had to have happened for this to be true is just unbelievable, and probably completely unprecedented in paleontology," said Schein.

The paleontologists will publish their research in the next edition of the annual journal Proceedings of the Academy of Natural Sciences of Philadelphia.