Chicago's Magnificent Museums: Field Museum behind-the-scenes-look

CHICAGO (WLS) -- Roz Varon has been exploring Chicago's Magnificent Museums, taking us behind the scenes, where visitors rarely go!

On Friday, she shares some surprises about the Field Museum.

The Field Museum actually started as the 1893 Columbian Exposition was ending. Benefactors bought all these artifacts and specimens from the World's Fair and opened a museum on that site where the Museum of Science and Industry now stands!

But the World's Fair buildings were never meant to be permanent, so a new museum was built on a new site.

The Field Museum opened in Grant Park in 1921, with about 5,000 artifacts. Today, there are nearly 40 million objects, including favorites, Sue, the T-Rex and Maximo the world's largest dinosaur, but just a fraction of these large fossils are on display. The rest are stored in an underground research facility.

"What a collection manager does is very similar to what a librarian does, but instead of books, in my case it's Field Museum's vertebrate fossils," Bill Simpson, head of geological collections and manager of vertebrates at the Field Museum. "This is where the biggest fossils are, the dinosaur collection."

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The museum's first paleontologist, Elmer Riggs also discovered the museum's first brand new dinosaur that turned out to be the largest dinosaur at the time, and for the next half century!

"When you find a new organism you get to name it, he named it Brachiosaurus which means arm lizard," Simpson said. "It's not a lizard, but that's the Greek that's used for dinosaur's often."

Not every exciting discovery has to be larger than life!

"What we got from the Jurassic of Madagascar we got a little jaw, it's a jaw fragment about this big, it has three teeth in it," Simpson said. "It turned out to be the oldest mammal that's been found in Madagascar!"

From fossils of dinosaurs and flightless terror birds onto the current bird research center.

"We have about 570,000 specimens, 10,800 species of birds," John Bates, curator of birds at the Field Museum. "We've got an incredible data set of birds that have hit the windows at McCormick Place during spring and fall migration. Live birds go to the rehab center where they're released, dead birds come to us. It's a spectacular data base...in a way that we can look at change over time. Body sizes on these birds, almost all across the board in this case is actually going down and that's something that's potentially, completely consistent with climate change."

The egg room contains a wide variety of eggs in all colors, shapes and sizes. Some common murre eggs come from a bird that breeds on North American cliffs. The shape keeps them from rolling off a ledge. The unique color and pattern has a purpose too.

"The evolutionary trait to be able to individually mark your egg as it's going down the ova ducts such that you can identify it and find it in this massive colony of hundreds of breeding common murres," Bates said.