Scientists have been scrapping old notions about dinosaurs eversince they discovered fossilized remains of nests of baby dinos at"Egg Mountain" in Montana.
Contrary to previous belief, dinosaurs apparently didn't abandontheir babies after hatching.
The Montana excavations also support a controversial theory thatat least some dinosaurs were warm-blooded and relativelyfleet-footed, not lumbering, cold-blooded beasts.
Bone fragments, models and casts of eggs and babies from thesite recently went on display at the Chicago Academy of Sciences,2001 N. Clark. The "Lives of the Dinosaurs" exhibit also includes 40photographs and drawings of the 75 million-year-old dinosaurs.
The exhibit, located on the third floor of the nature museum,complements the Dino-rama display of 12 nearly lifesize dinosaurmodels on the museum grounds.
Between 1978 and 1984, paleontologist Jack Horner and colleaguesdug up more than 500 eggs in a square mile area near Choteau, Mont.They also found thousands of eggshell fragments, parts of 150dinosaur skeletons and four nests containing the remains of dinosaurbabies. These were the first nests of baby dinosaurs found anywherein the world.
Many fossils come from the duckbill dinosaur, which laid anaverage of 20 eggs in hollowed-out ground nests about 3 feet by 6feet. The nests were covered with rotting vegetation to keep theeggs warm.
Fossil evidence indicates that newly hatched duckbill dinosremained in the nest and were cared for by their mothers. Forexample, some babies found in nests were 2 1/2 times larger thannewborns. Moreover, the bones in baby skeletons probably were notstrong enough to enable them to walk immediately.
A second species, known as Orodromeus, apparently left the nestat birth but stayed near its mother.
If, as Horner suggests, dinosaurs cared for their young, theybehaved more like birds than reptiles. With rare exceptions,reptiles abandon their young.
The bone structure of dinosaurs also is birdlike, especially thelegs and upright stance. Horner agrees with scientists who saydinosaurs should not be considered cold-blooded reptiles, but beplaced instead in a class with warm-blooded birds.
Dino-rama is open through Labor Day, and the Montana exhibit ison display through Sept. 25. Tickets are $4 for adults and $2.50 forchildren and seniors.
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