Mini-Assignment 6: Prepare for the next excavation lab (caudal bones and trace fossils)
To answer the questions below, read pages 226-231 about dinosaur trace fossils and see box 6.1 and page 341 for information about the skeletal regions you’ll seen
in lab this week.
1.
What trace fossil could serve as evidence that main dinosaur you are excavating was predated upon? (1 pt)
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The trace fossil that could serve as evidence the dinosaur you’re excavating was predated upon would be tooth marks left on the bones. The tooth marks
could indicate that another predator fed on the dinosaur. 2.
What evidence could you use to support that a given coprolite was made by a dinosaur? What might give you uncertainty about what animal made the coprolite? (2 pts)
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Evidence to support a given coprolite was made by a dinosaur could be the presence of undigested bone fragments or plant matter within the coprolite. We might have an uncertainty about what animal made the coprolite because crocodiles also produce similar coprolites.
3.
The ventral bones beneath the skeleton are called chevrons. What are the functions of chevrons? (1 pt)
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They can provide support and protection for the tail, help stabilize the tail during locomotion, and help in balance. 4.
What are the two types of bones represented in the caudal region of the organism’s skeleton? (1pts)
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The two types of bones in the caudal region are the caudal vertebrae and the chevrons. 5.
Examine the figures of these dinosaur tails. You may need to be logged in to the library using your NetID and password to view some images. Describe the differences you see among the taxa using at least 5 of the following terms
: centrum, neural arch, neural spine, transverse process, chevron, osteoderm, caudal, sacral (5 pts)
Ankylosaur:
https://journals.plos.org/plosone/article/figure/image?size=large&id=10.1371/journal.pone.0006738.g001
Titanosaur:
https://media.springernature.com/full/springer-static/image/art%3A10.1038%2Fsrep06196/MediaObjects/
41598_2014_Article_BFsrep06196_Fig1_HTML.jpg?as=webp
Spinosaur:
https://media.springernature.com/full/springer-static/image/art%3A10.1038%2Fs41586-020-2190-3/MediaObjects/
41586_2020_2190_Fig1_HTML.png?as=webp
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Centrum
Ankylosaur had a squat centrum to support their armored plates. A Titanosaur had a more elongated slender centrum. And the Spinosaur had an elongated and streamlined centrum. -
Neural arch
Ankylosaur had heavy armored neural arches. The Titanosaur had less pronounced neural arches in comparison to the Ankylosaur. And the Spinosaur’s neural arch was adapted most likely to support the sail on their back.
