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Predation affects body shape in the knife livebearer Alfaro cultratus (Cyprinodontiformes: Poeciliidae)
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  • Diego Ardon,
  • Kaitlyn Golden,
  • Trevor Williams,
  • Mark Belk,
  • Jerald Johnson
Diego Ardon
Brigham Young University

Corresponding Author:[email protected]

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Kaitlyn Golden
Brigham Young University
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Trevor Williams
Brigham Young University
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Mark Belk
Brigham Young University
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Jerald Johnson
Brigham Young University
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Livebearing fishes are a standard model for studying the effect of predation on prey biology. Numerous studies have found differences in life history, sexual selection, behavior, and morphology between populations of the same species that co-occur with predators and those that do not. Alfaro cultratus is a livebearing fish with populations in different predation environments, but unlike other livebearers, this species also has an extreme body shape that is laterally compressed. Given this unusual morphology, we asked if predation environment would still predict overall body shape, as has been documented in other species. We collected specimens from both predator and no-predator sites in Costa Rica. We used a geometric morphometrics analysis to determine if body shape is affected by the predation environment while controlling for size and river gradient. Body shape does indeed differ between predation environments; however, the observed differences contrast with the patterns found in other livebearer systems. Alfaro cultratus in predation environments had deeper and shorter bodies and deeper caudal peduncles than those found in environments without dominant fish predators.
24 Aug 2023Submitted to Ecology and Evolution
30 Aug 2023Submission Checks Completed
30 Aug 2023Assigned to Editor
04 Sep 2023Reviewer(s) Assigned
15 Oct 2023Review(s) Completed, Editorial Evaluation Pending
17 Oct 2023Editorial Decision: Revise Minor
03 Nov 20231st Revision Received
08 Nov 2023Assigned to Editor
08 Nov 2023Submission Checks Completed
08 Nov 2023Review(s) Completed, Editorial Evaluation Pending
13 Nov 2023Editorial Decision: Revise Minor
16 Nov 20232nd Revision Received
17 Nov 2023Review(s) Completed, Editorial Evaluation Pending
17 Nov 2023Submission Checks Completed
17 Nov 2023Assigned to Editor
18 Nov 2023Editorial Decision: Accept