It was a paleontologist's dream find: a three-and-a-half foot thigh bone from a Tyrannosaurus rex, preserved wonderfully in the Montana ground. But when the scientists tried to load the femur onto their tiny helicopter, they realized to their dismay it would not fit. Tragically, they would have to break the precious bone to fit it on board.
But the tragedy now looks like a case of fortunate providence: By breaking the fossil, the scientists found unexpected material inside that looked like cellular soft tissue.
The shocking discovery contradicts scientists' conventional wisdom that the process of fossilization is necessarily accompanied by the loss of soft tissue, which contains remnants of cellular structures and possibly genetic material.
This March, nearly two years after the 2003 discovery of the bone, lead investigator Mary Schweitzer, assistant professor of paleontology at North Carolina State University, announced a successful extraction. She had successfully isolated structures that looked astonishingly like blood vessels and blood cells from the 68-million-year-old fossil.
She was also able to repeat her discovery with three other dinosaur specimens, thus becoming the first team to ever observe soft tissue in a dinosaur fossil.
\We may not really know as much about how fossils are preserved as we think,"" Schweitzer said in a news release, but now those beliefs are poised to change. These fossils could help scientists ""learn more not only about the dinosaurs themselves, but also about how and why they were preserved in the first place,"" she said.
Because birds are thought to be the closest living relatives of dinosaurs, Schweitzer compared the T. rex findings to observations of a modern-day ostrich's bone structures. In both samples, Schweitzer identified transparent branching blood vessels, and noted that many small structures in the T. rex blood cells were remarkably similar to those in the ostrich's blood cells.
Scientists hope this will settle the age-old debate of whether dinosaurs were cold- or warm-blooded, and also provide insight into how they lived their daily lives. According to Joseph Skulan, UW-Madison assistant faculty associate of geology, this discovery could also reveal what factor determined a dinosaur's gender: whether it was genetic as with most mammals, or temperature-influenced as with some reptiles.
Sarah Howard, a UW-Madison sophomore and a big fan of the ""Jurassic Park"" trilogy, was excited to learn about the paleontological breakthrough.
""I can't wait to see what happens,"" she said. ""If they can really get DNA, that is such a huge finding.""
But does this discovery signal the beginning of a real-life ""Jurassic Park?"" Not quite yet, Skulan said. Even if scientists can isolate DNA from the soft tissue, many factors still hinder any attempts to clone a dinosaur. For one thing, a scientist would need more than just dino-DNA.
""It is simply false to think that all the instructions [for development] are in the genes,"" he said. The DNA would have to be inserted into a living cell that closely resembles T. rex soft tissue, which would be hard to find. More likely, Skulan theorized, would be the cloning of a mammal like the mastodon, which is believed to be closely related to elephants.
The more promising short-term avenues of inquiry include understanding dinosaurs' lifestyles, determining warm- or cold-bloodedness and resolving the gender of individual fossils.
