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Degree Name

Biological Sciences - Ecology and Natural Resources: M.S.




College of Science and Engineering

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Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Keywords and Subject Headings

anglerfishes, evolution, lures, ichthyology, phylogenetics, geometric morphometrics


The anglerfishes (Lophioidei) consist of carnivorous fishes renowned for their first dorsal-fin spine luring specialization used in prey capture behavior. Anglerfishes encompass a unique fish lineage (>400 species) distributed at varying oceanic depths that have resulted in fascinating evolutionary adaptations, including pseudo-walking, chemical prey attractant lures, bioluminescent lures and barbels, sexual dimorphism, and male parasitism. Chapter one of this thesis investigates the evolutionary relationships of the suborder Lophioidei using a total evidence approach. A total evidence approach is a strategy used to infer evolutionary relationships that combine different lines of evidence, such as morphological and genetic data, to provide a robust hypothesis of evolutionary relationships and is used to investigate the evolution of anglerfishes (Acanthuriformes: Lophioidei). In this thesis I explore the evolutionary relationships of Lophioidei with ultraconserved elements (UCEs), UCEs and mitochondrial genomes, and a total evidence approach that combines UCEs, mitochondrial genomes, and morphological characters. The results of these analyses recover a monophyletic Lophioidei as the sister group to Tetraodontoidei within Acanthuriformes, with Lophioidei+Tetraodontoidei sister to the boarfish Antigonia (Caproidae). Within Lophioidei, the goosefishes (Lophioideo) were inferred as the stem anglerfish lineage. The Lophiidae are the sister group to a clade comprised of the frogfishes (Antennarioideo) + batfishes (Ogcocephaloideo) and the coffinfishes (Chaunancoideo) + deep-sea anglerfishes (Ceratoideo). Chapter 2 explores the luring apparatus of anglerfishes, the primary tool used in prey capture and communication in certain groups. The anglerfishes have three distinctive luring strategies: mechanical luring, chemical attractant luring, and bioluminescent luring. Anglerfish specimens and photos procured from ichthyological museum collections and online public databases are used to collect morphometric data from the lures of these fishes. Depth records collected from FishNet 2 are then used to examine lure morphometrics based on various oceanic depths. Using the total evidence tree in Chapter 1, the study recovers two independent evolutionary events of a mechanical luring strategy in Lophioidei and Caulophrynidae, one independent evolutionary event of bioluminescent luring in Ceratoideo, two independent evolutionary events of chemical attractant luring in Antennarius striatus and Ogcocephaloideo, and a single event of the luring apparatus found in Neoceratidae. Lure total length to standard length ratios from smallest to largest include Chaunacoideo 0.047, Antennarioideo 0.186, Lophioideo 0.208, and Ceratoideo 0.443, indicating deep-sea pelagic anglerfishes have the highest lure to standard length ratios. Chapter 3 continues the investigation of habitat impacts on Lophioidei to investigate body shape changes and lure ranges. A geometric morphometric analysis is performed on the same taxa used in Chapter 2, while also measuring luring ranges in degrees based on videos and photos as a reference to set parameters for the radial range of which these fishes can move their lures. We found the luring ranges to be highly variable across Lophioidei with lateral body shapes exhibiting significant disparities between chemical lures compared to bioluminescent lures (P value: 0.064) and mechanical lures (P value: 0.069). Body shape disparities were also found between Bathypelagic and Abyssopelagic anglers and between the Ceratoideo compared to Lophioideo (P value: 0.034), Antennarioideo (P value: 0.001), and Ogcocephaloideo (P value: 0.020).


I would like to thank the following institutions and people for providing specimens, facilities, and equipment used in this study including Wm. Leo Smith (KU), Bill Ludt and Todd Clardy (LACM); Edda Aßel (ZMB); Jonathon Pfliger (MNHN); Sally Reader (AMS). Funding for this work was provided by the National Science Foundation (DEB 1258141 NSF), the Natural History Museum of Los Angeles County (LACM) Student Collections Study Award, St. Cloud State University (SCSU) Student Research Grants, the Hellervik Award, Midcareer Grant, and Proposal Enhancement Grant. I would also like to thank Rene Martin (AMNH) for her discussion on geometric morphometric methods and analyses used in chapter 3 and Wm. Leo Smith (KU) for his thoughts on figures. I would also like to thank my committee members Matthew Davis, Sarah Gibson, and Jennifer Lamb for their insights and feedback, as well as the contributions they have made to my education during my undergrad and graduate programs that I will forever cherish. The current and former members of the Davis Fish Lab including Spencer Ott, Molly Clyne, Michelle Lanam, Zach May, and Emily DeArmon all have my thanks for their knowledge exchange and support. Additionally, I would like to thank my parents, Jodi and Randy Maile, as well as my fiancé Megan Hassing for their motivation and support in my academic career and for always encouraging me to pursue my dreams. Finally, I would again like to thank my advisor Matthew Davis for giving me the opportunity to pursue an academic path that involves my love of fishes and evolution, for his teachings relating to ichthyology, phylogenetics, bioluminescence, biofluorescence, and for his mentorship for the past 6 years. Thank you, Matt.

Available for download on Tuesday, April 23, 2024