Submission Type
Poster
Start Date
April 2020
Abstract
Mononykus olecranus was a small, nonavian predatory theropod that exhibited unusual forelimb size in comparison to other theropods. The forelimbs were distinctly stunted in size with only one finger and claw on each hand. The perplexity of these forelimbs has prompted many to study the function of the Mononykus forelimbs. This study uses phylogenetic muscle reconstruction methods along with previous reconstructions of theropods such as Tawa and Majungasaurus to help us better understand what Mononykus may have been capable of. Overall, there are several modifications in the forelimb that improve the leverage of the shoulder flexors and elbow extensors. An improved lever arm for shoulder flexors like Supracoracoideus would be provided by the enlarged posteroventral process of the scapulocoracoid and the projecting deltopectoral crest of the humerus. Improved leverage for elbow extensors like Triceps brachii would be shown by the massive olecranon process of the ulna and enlargement of the ectepicondyle of the humerus. The humerus also shows an enlargement of internal tuberosity related to the shoulder adductors. These reconstructions, along with the rest of the forelimb, are consistent with the hypothesis that Mononykus used its unusually small forelimbs for digging or scratching, perhaps when foraging for insects.
Recommended Citation
Smith, Jada, "153— Muscular Reconstruction of the Forelimb of the Theropod Dinosaur Mononykus olecranus" (2020). GREAT Day Posters. 95.
https://knightscholar.geneseo.edu/great-day-symposium/great-day-2020/posters-2020/95
153— Muscular Reconstruction of the Forelimb of the Theropod Dinosaur Mononykus olecranus
Mononykus olecranus was a small, nonavian predatory theropod that exhibited unusual forelimb size in comparison to other theropods. The forelimbs were distinctly stunted in size with only one finger and claw on each hand. The perplexity of these forelimbs has prompted many to study the function of the Mononykus forelimbs. This study uses phylogenetic muscle reconstruction methods along with previous reconstructions of theropods such as Tawa and Majungasaurus to help us better understand what Mononykus may have been capable of. Overall, there are several modifications in the forelimb that improve the leverage of the shoulder flexors and elbow extensors. An improved lever arm for shoulder flexors like Supracoracoideus would be provided by the enlarged posteroventral process of the scapulocoracoid and the projecting deltopectoral crest of the humerus. Improved leverage for elbow extensors like Triceps brachii would be shown by the massive olecranon process of the ulna and enlargement of the ectepicondyle of the humerus. The humerus also shows an enlargement of internal tuberosity related to the shoulder adductors. These reconstructions, along with the rest of the forelimb, are consistent with the hypothesis that Mononykus used its unusually small forelimbs for digging or scratching, perhaps when foraging for insects.
Comments
Sponsored by Dr. Sara H. Burch