This is Throwback Thursday #137. In these, we look back into the past at ESCONI specifically and Earth Science in general. If you have any contributions, (science, pictures, stories, etc ...), please sent them to esconi.info@gmail.com. Thanks!
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October 1997 was a huge month for the Field Museum. The annual meeting of the Society of Vertebrate Paleontology (SVP) was held there from October 8th-11th, 1997. This is an important meeting held each year. Jack Horner was named Acting President. He had just released his new book "Dinosaur Lives". Oh... and Archaeopteryx was on display for the first and only time in the US. It would be on display for only two weeks from October 4th to the 19th, 1997.
And, ESCONI was there as you can see from the announcement in the ESCONI newsletter.
Definitely not to be missed... unfortunately, I missed it! ESCONI even had a field trip to see it... on its last day.
ARCHAEOPTERYX: THE BIRD THAT ROCKED THE WORLD
A Famous Fossil Lands In North America for the First Time
October 4-19, 1997
In 1861, paleontologists made a shocking discovery in a German limestone quarry. Etched in a 150-million- year-old slab of rock was a creature almost to strange to believe. It looked like a small dinosaur with a long tail, sharp teeth, and clawed forelimbs. BUT it had feathers and wings like a bird!
Named Archaeopteryx for "ancient wing", the prehistoric bird was hailed as a "missing link" between dinosaurs and birds. In the next 136 years, only six other fossil Archaeopteryx skeletons were unearthed, all in the famous Solnhofen limestone quarries of Bavaria, Germany. Not one of the famous seven fossils has ever been exhibited outside Europe -until now.
For the first time in North America, an Archaeopteryx will be on display at the Field Museum from October 4 to 19, 1997. This is a once in a lifetime opportunity to see an original specimen of Archaeopteryx here in the United States. "It's a very rare and extremely important fossil one of the most famous in the world." said Field Museum paleontologist Olivier Rieppel.
It was the first transitional fossil ever found. A transitional fossil helps scientists understand how a new group of organisms, in this case birds, evolved from an existing group, reptiles. Fossils in general are rare; transitional fossils are very rare.
It was Charles Darwin who first predicted the existence of transitional animals with his theory of evolution. The first Archaeopteryx fossil, found just two years after Darwin's "Origin of Species" was published, was hailed as "living proof" of his then controversial theory. Six more specimens of Archaeopteryx were found in 1876, 1951, 1956, 1970, 1987, and 1992 -all in the Solnhofen limestone quarries of Germany. The seventh and most recent find will be on exhibit at the Field Museum.
When you start giving a fossil numbers, you know how rare it is. Only three of the fossils have individual feathers clearly preserved in the stone the specimen coming to Chicago is one of them. John Flynn chairman of the Museum's geology department says the exhibit was made possible through close working relationships between Field Museum curators and their German colleagues. Peter Wellnhofer, an expert on Archaeopteryx and pterosaurs (flying reptiles) and curator for the State Museum of Paleontology and Historical Geology in Bavaria, will accompany the fossil to America. He will be in Chicago for the duration of the exhibit and will give a public talk about the prehistoric bird at 2:00 p.m. on Saturday, October 18, at the Museum. He will also participate in the 57th annual meeting of the Society of Vertebrate Paleontology, hosted by the Museum October 8-11.
All of the Archaeopteryx fossils were unearthed in the Upper Jurassic Solnhofen limestone quarries that cover a 516 square mile area near Solnhofen, Germany, and date to around 150 million years ago.
Solnhofen limestone is extremely fine grained. The rock is quarried commercially for use in lithographic printing, which is why the fossils in it are so incredibly detailed.
Even the soft parts of animals like crabs, insects and jellyfish have been preserved in Solnhofen limestone. In fact, the preservation is so good that scientists have reconstructed an entire oceanic ecosystem where Archaeopteryx lived. Remnants of ancient reefs, islands and marine lagoons in the limestone have yielded more than 450 species of animals that lived in the area 150 million years ago, including 8 species of jellyfish consisting entirely of soft body parts.
Solnhofen limestone formed in what was once a shallow and stagnant marine lagoon. "The bottom of the lagoon had no oxygen, so the dead animals that fell to the bottom of it did not decay," says Flynn. Bird fossils with feathers are rare because conditions necessary for the preservation of feathers are very unusual.
Only one dinosaur species has been recovered so far in the Solnhofen rock. Compsognathus, a small ground-dwelling dinosaur that ran on its two hind legs. It is a theropod dinosaur, the group most closely related in physical structure to Archaeopteryx. A cast of a fossil skeleton of Compsognathus will be displayed in the exhibit, along with many marine fossils from Solnhofen.
The exhibit will also feature a lifelike reconstruction of Archaeopteryx that was based on fossil evidence. Greg Septon of the Milwaukee Public Museum used teeth from a rainbow trout and plumage and body parts from seven different species of birds from around the world to bring Archaeopteryx to life.
In the last 10 years, several new species of prehistoric birds have been found in areas ranging from Africa to China, providing more and more evidence of ancestral ties with dinosaurs. Archaeopteryx is still the oldest known and most primitive bird.
Although the bird-dinosaur link is now widely accepted (some scientists call birds "living dinosaurs"), a handful of skeptics insist that dinosaurs and birds evolved separately from a common reptilian ancestor. New findings are making the transition of reptiles to birds a rewarding field to work in. Now the gaps are starting to fill in, and it is getting more and more interesting.
One of the great unsolved riddle of Archaeopteryx is: Could the world's oldest known bird fly?
Each feather on an Archaeopteryx wing is arranged asymmetrically along the shaft, just like modern birds that fly. (Birds what are flightless have feathers that are arranged symmetrically.) Archaeopteryx may have been capable of active flight. At the very least, the prehistoric bird was probably able to glide short distances after jumping off a tree branch.
"This question of whether Archaeopteryx could fly or not relates to the origin of feathers," says Flynn. "Did they evolve for flight, or first for insulation, and only later becoming further adapted to enable flight?
Archaeopteryx is critical to understanding the evolution of many features found in modern birds.
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During October a Lecture Series, Family Workshops and a Family Evening and an Adult Course will be offered. For more information or to register contact the Field Museum Education Department at 312-322-8854.
