Contents: One orange Velociraptor claw cast
This is the slashing claw from the foot of a Velociraptor.
Contents: One green/gray cast of a Deinonychus foot
Deinonychus, which is currently on display in the Hall of Giants, was a raptor similar to a Velociraptor (from Mongolia). Deinonychus means “terrible claw.” This is a cast of a right foot excavated in the early 1990’s from the Cloverly Formation near Bridger, Montana. It is from the Early Cretaceous period (about 112 million years ago). The second toe of the foot was the slasher claw and the third and fourth toes were weight bearing. The slasher toe could flex 180 degrees and had an outer sheath probably another inch longer. The shape of the claws is similar to that of animals that climb. New research shows that Deinonychus may have climbed prey much larger than itself. Deinonychus was a quick and agile bipedal runner who may have travelled in packs. This dinosaur was about 3 feet tall at the hip, 8-11 feet long and weighed 165-175 lbs.
Contents: Three identical casts of a Deinonychus Tooth (one white, two gray resin)
This Deinonychus tooth is a cast of the real one which is on display in the Hall of Giants (all three are the same tooth). Deinonychus teeth have been found in association with the fossilized skeleton of Tenontosaurus. Deinonychus replaced their teeth throughout their lifetimes.
Tenontosaurus Lower Left Jaw with Teeth
Contents: one white resin jaw cast
The wear pattern is visible on the outside of the teeth in this lower left jaw section from the Early Cretaceous plant eater Tenontosaurus.
Contents: one real fossilized horn core
This real fossil is a part of a Triceratops horn core. The channels on the surface of this fossil indicate that it was covered by a keratin (fingernail material) sheath.
Encourage visitors to touch the fossil and ask them what they think it is. Encourage them to make descriptive observations. What do you think this is? What do you notice about it? Would the real horn have been this heavy?
Encourage visitors to compare the fossilized horn with a replica of a horn. What are the similarities? What are the differences?
Contents: two brown casts of horns
Keratin (the material your fingernails are made of) does not fossilize. The horns found as part of fossilized ceratopsian (horned dinosaur) skulls are actually horn cores that would have been covered by a keratin sheath, just like horned animals today. Close study of horn cores indicates a hollow base. Dr. Jack Horner believes this indicates a weakness in the horn that could have caused it to break off if the Triceratops used its horns for defense. Hollow horn cores are therefore one argument against this defensive behavior by Triceratops, although not all scientists agree that the hollow is indicative of weakness. Dr. Jack Horner now thinks that Triceratops used its horns and frill for species recognition. Since horned dinosaurs of a given species are similar in body shape, differences in skull ornamentation would allow for differentiation between species. (Jack Horner’s Docent Talk, 6/6/05)
Hand the replica to visitors and ask them what they think it is. Encourage them to make descriptive observations. What do you think this is? What do you notice about it? This is especially effective if you have just shown the visitors teeth—many think the horn is a tooth!
Encourage visitors to hold the horn up to their head in the correct position. What would it have been like to have these protruding from your face? What might they have been used for?
Encourage visitors to discuss what the horns were used for. Point out the hollow end of the horn. Could the hollow base of the horn change our ideas about how it was used?
Ceratopsians, or horned dinosaurs had many teeth that fit together to form tooth batteries. Each individual tooth had a spade-shaped exposed surface and a bifurcated (double) root. The teeth fit together in an offset pattern allowing various teeth to wear down faster than others (similar to hadrosaurs—duck-billed dinosaurs).