Minnesota's Growing Paleontologist Population

Minnesota, land of very few dinosaur fossils, has somehow managed to become the land of leading paleontologists—and they've made some incredible discoveries.

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Minnesota ranks first on any number of lists—from most hockey players to fittest cities to best state fair.

One thing our Land of 10,000 Lakes lacks—besides temperate Januaries, that is? Dinosaurs. Er, dinosaur fossils, to be precise.

“Dinosaurs were here, and it was probably a fun place to live,” says Macalester geology professor Raymond Rogers. “Back in the days of dinosaurs, Minnesota was on the eastern shores of the Western Interior Seaway. If you went to western Minnesota, you’d have beautiful waterfront property.”

But even though researchers do occasionally find a piece or scrap of tooth or vertebra that could have belonged to a dinosaur, conditions in Minnesota were not great for preserving bones.

What Minnesota lacks in dinosaur bones, it makes up for in dinosaur experts. By chance, a handful have recently landed in roles at the University of Minnesota, the Science Museum of Minnesota, and Macalester College. The fossil enthusiasts consider each other colleagues and gather every few weeks to talk shop over beer.

“I spent the first several years of my career at [the University of Minnesota] as the only paleontologist around, and over the years, the numbers of paleontologists on campus, in the Twin Cities, and in Minnesota have grown considerably,” says U of M professor David Fox. “So now we have an uncommonly large community, which is great, and I think only exceeded by cities such as New York, Chicago, and L.A. that have world-scale natural history museums and numerous research universities.”

The enthusiasm and curiosity of Minnesotans help make up for the dearth of local fossils, says Science Museum paleontology curator Alex Hastings. “Minnesotans are citizens of the world, traveling all over and finding new things,” he says. “The beauty and glory of Minnesotans is that we’re not just interested in learning about our state here.”

In that vein, we asked a few of the experts to share their stories of extraordinary finds from far-flung locales.

A Giant Carnivorous Dinosaur with Tiny Arms

With the temperature hovering around 113 degrees Fahrenheit on the first day of a dig in Argentina in 2012, paleontologist Peter Makovicky, now a U of M professor, and colleagues decided to take a break—that is, until Makovicky’s collaborator returned with half of a big vertebra in his backpack. Unlike other digs, this one felt special from that moment on, Makovicky says. Usually, researchers spend days poking around, with the best finds often coming on the last day. This time was different: Not only had they stumbled across a dinosaur graveyard, but the vertebra appeared to be from a previously unknown species.

“We had a sense that this was going to be new and exciting,” he says. “We knew we had a lot of the specimen preserved and that the quality of the preservation was excellent.”

They found pieces of four dinosaurs that were significantly different from others of the same era. The team celebrated with a swim at a nearby reservoir before starting the “backbreaking work” of digging the bones out, Makovicky says.

Eventually, after the bones were excavated and packaged in plaster and sent to a museum in the small nearby town of Villa El Chocón, Makovicky’s team realized they had some clues to a question that has stumped paleontologists about this family of large theropods (types of carnivorous dinosaurs): Why do these giant meat-eating dinosaurs, including the Tyrannosaurus rex, have dinky little arms?

The fossils they’d found make up the most complete skeleton of the family (Carcharodontosauridae) found to date in South America. And they helped the scientists develop an explanation recently published in the journal Current Biology: The animals likely evolved to hunt larger prey by developing a bigger head that measures about 4 feet. The trade-off, researchers believe? Smaller arms.

“So, the T. rex has small arms not just because it happens to, but because there’s some sort of pressure on the group that they would need to be reduced to have the big head and the big body,” Hastings says of Makovicky’s work. “It’s going to invest in one or the other, so you could have this awesome, cool head that’s powerful enough to bite through many things, or massive arms and claws. They don’t go together.”

Makovicky voted to name the newly discovered creature the word for “ruler” in the local language, but his Argentinean colleague Juan Canale won out with the Game of Thrones–inspired Meraxes gigas.

A Lizard-like Long-necked Sauropod

Before Macalester professor Kristi Curry Rogers’s team found an almost complete titanosaur in Madagascar, the type of dinosaur was known only by “a head here, a tail there,” she says.

Curry Rogers and her now husband, Ray Rogers, have been searching the hills of Madagascar for dinosaurs on and off since the 1990s.

“Once we identify a few pieces of bones, then it’s like ‘Hansel and Gretel,’” Curry Rogers says. “We trace little bits up a hill slope, do some exploratory digging. When we’re really lucky, they lead to more bone that haven’t been exposed to the surface.”

This was one of the lucky digs.

Curry Rogers wants to find out how long-necked, long-tailed sauropods grow from very small babies— hatched from eggs the size of a grapefruit—to some of the biggest dinosaurs of all time. To do that, she cuts pieces out of the middle of their bones and grinds them down on a wheel by hand until she can see patterns of blood supplies and cells through a microscope. The Rapetosaurus—named after a “mischievous giant” in Malagasy folklore—helped her realize that these dinosaurs grow much faster than people used to think, more on the scale of mammals or birds.

In less than 30 years, the biggest Rapetosaurus dinos could grow to 100 feet long and 100 tons, she says.

“The Rapetosaurus was really susceptible to the ecosystem and died all the time,” says Ray Rogers, noting that the number of juvenile animals at the site suggests mass mortality events, probably due to drought.

A Giant Prehistoric Snake called Titanoboa

This is not a dinosaur find, but “who doesn’t love a giant snake?” says the Science Museum’s Alex Hastings.

Hastings was researching crocodiles in coal mines in northern Colombia during work on his PhD at the University of Florida. When a colleague there who was studying turtles shipped Hastings some material he’d found while looking for turtles, Hastings noted a vertebra around 6 or 7 inches across, and he knew it hadn’t belonged to a crocodile. It seemed much too big to belong to a snake; a vertebra of a python is about 1 inch across.

“It’s like the difference between a mouse and a rhinoceros,” he says.

But after a minute, he realized, “Holy cow, these are snake bones.” The snake is now believed to have been longer than a school bus, weighing 1.25 tons. It could have eaten a crocodile in a single gulp.

Beyond the wow factor and bragging rights, Hastings’s work ended up becoming relevant for a seemingly unrelated reason: He was able to estimate the temperature of the tropics 66 million to 56 million years ago, which has implications for the understanding of climate change.  Previously, it was believed that the tropics could have been buffered from climate temperature increases. But since snakes are cold-blooded animals, the researchers surmised that it had to have been very hot for the snakes to live.

The snakes show that “the tropics had every potential to have had the thermostat way up,” he says. And you don’t need to leave Minnesota to see Titanoboa: The life model developed by the Smithsonian is on display at our own Science Museum.

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