Question
Donald M. Henderson disproved the theory that plesiosaurs and crocodilians relied on these objects to maintain buoyancy, but suggested that these objects prevented them from rolling on their sides. For 10 points each:
[10h] Name these smooth, round objects that are typically found in the rib cages of herbivorous dinosaurs and toothless theropods. These objects are sometimes named for Colorado’s Morrison Formation.
ANSWER: gastroliths [or gizzard stones or stomach stones; accept Morrison stones; prompt on stones or rocks or pebbles]
[10m] Gastroliths can be used to track the migrations of these large “lizard-hipped” dinosaurs, whose tails did not produce sonic booms. The air sacs of these dinosaurs contributed to the relatively lightweight nature of their necks.
ANSWER: sauropods [or Sauropoda; prompt on Saurischia or Saurischians; prompt on individual sauropods such as Brachiosaurus, Diplodocus, Apatosaurus, Brontosaurus, Camarasaurus, Argentinosaurus, and others]
[10e] Gastroliths belonging to Diplodocus have been found in the Morrison Formation, which dates to this period. This middle period of the Mesozoic era sits between the Triassic and Cretaceous periods.
ANSWER: Jurassic period
<KT, Biology>
Summary
| 2023 ARCADIA at Duke | Emory, Duke, Yale | Y | 4 | 12.50 | 100% | 25% | 0% |
| 2023 ARCADIA at Emory | Emory, Duke, Yale | Y | 4 | 25.00 | 100% | 75% | 75% |
| 2023 ARCADIA at Imperial | Imperial | Y | 5 | 16.00 | 100% | 40% | 20% |
| 2023 ARCADIA at Maryland | Maryland, Online | Y | 3 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at Ohio State | Ohio State, Texas | Y | 3 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA Online | Maryland, Online | Y | 3 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at Texas | Ohio State, Texas | Y | 3 | 20.00 | 100% | 33% | 67% |
Data
| Georgetown | George Washington B | 0 | 0 | 10 | 10 |
| George Washington A | Johns Hopkins | 0 | 0 | 10 | 10 |
| Maryland A | Maryland B | 0 | 0 | 10 | 10 |