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Title: Evolutionary patterns of scale morphology in damselfishes (Pomacentridae)
Abstract

Fish scales are bony plates embedded in the skin that vary extensively in shape across taxa. Despite a plethora of hypotheses regarding form–function relationships in scales, we know little about the ecological selective factors that shape their diversity. Here we examine evolutionary patterns of scale morphology using novel three-dimensional topography from the surfaces of 59 species of damselfishes, a prominent radiation of coral reef fishes. We find evidence that scale morphology changes with different flow environments, such that species that spend more time in open-water habitats have smoother scales. We also show that other aspects of ecology lead to highly derived scales. For example, anemonefishes show an evolutionary transition to smaller scales and smaller ctenii (scale spines). Moreover, changes in body shape, which may reflect ecological differentiation, are related to scale shape but not surface properties. We also demonstrate weak evolutionary integration among multiple aspects of scale morphology; however, scale size and shape are related, and scale morphology is correlated between different body regions. Finally, we also identify a relationship between aspects of lateral line pore morphology, such that the number of lateral line pores per scale and the size of those pores are inversely related. Overall, our study provides insights into the multidimensionality of scale evolution and improves our understanding of some of the factors that can give rise to the diversity of scales seen across fishes.

 
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Award ID(s):
1907156
NSF-PAR ID:
10361032
Author(s) / Creator(s):
; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Biological Journal of the Linnean Society
Volume:
135
Issue:
1
ISSN:
0024-4066
Page Range / eLocation ID:
p. 138-158
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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