Precise occlusion and trophic niche differentiation indicate specialized feeding in Early Devonian jawed vertebrates

• Published in: FACETS
• Main Author: Stephanie A. Blais
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2017
• Subjects: ischnacanthiform; acanthodian; Devonian; vertebrate jaws; bite mechanics; paleoecology; Education; L; Science; Q; Northwest Territories; Canada
• Online Access: https://doi.org/10.1139/facets-2016-0030; https://doaj.org/article/15e67e66a774478183ab977e5f5a3498

Acanthodians may represent a paraphyletic assemblage of stem chondrichthyans, stem osteichthyans, stem gnathostomes, or some combination of the three. One of the difficulties in determining the phylogenetic affinities of this group of mostly small, spiny fishes is that several subgroups of acanthodians are represented by relatively little information in the fossil record. It is becoming increasingly apparent that to understand the evolution of gnathostomes, we must understand more about acanthodians. This study uses micro-computed tomography to test hypotheses about acanthodian jaw function, and in doing so provides insight into the form, function, and ecological role of ischnacanthiform acanthodian jaws and teeth from an extraordinary Early Devonian fossil locality in the Northwest Territories of Canada. The results of this study suggest that ischnacanthiform acanthodians may have coexisted by trophic niche differentiation, employing specialized feeding strategies during the Silurian and Early Devonian.