Resource competition explains rare cannibalism in the wild in livebearing fishes
Abstract Cannibalism, the act of preying on and consuming a conspecific, is taxonomically widespread, and putatively important in the wild, particularly in teleost fishes. Nonetheless, most studies of cannibalism in fishes have been performed in the laboratory. Here, we test four predictions for the...
| Main Authors: | , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2022-05-01
|
| Series: | Ecology and Evolution |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ece3.8872 |
| _version_ | 1811256210413846528 |
|---|---|
| author | Rüdiger Riesch Márcio S. Araújo Stuart Bumgarner Caitlynn Filla Laura Pennafort Taylor R. Goins Darlene Lucion Amber M. Makowicz Ryan A. Martin Sara Pirroni R. Brian Langerhans |
| author_facet | Rüdiger Riesch Márcio S. Araújo Stuart Bumgarner Caitlynn Filla Laura Pennafort Taylor R. Goins Darlene Lucion Amber M. Makowicz Ryan A. Martin Sara Pirroni R. Brian Langerhans |
| author_sort | Rüdiger Riesch |
| collection | DOAJ |
| description | Abstract Cannibalism, the act of preying on and consuming a conspecific, is taxonomically widespread, and putatively important in the wild, particularly in teleost fishes. Nonetheless, most studies of cannibalism in fishes have been performed in the laboratory. Here, we test four predictions for the evolution of cannibalism by conducting one of the largest assessments of cannibalism in the wild to date coupled with a mesocosm experiment. Focusing on mosquitofishes and guppies, we examined 17 species (11,946 individuals) across 189 populations in the wild, spanning both native and invasive ranges and including disparate types of habitats. We found cannibalism to be quite rare in the wild: most populations and species showed no evidence of cannibalism, and the prevalence of cannibalism was typically less than 5% within populations when it occurred. Most victims were juveniles (94%; only half of these appeared to have been newborn offspring), with the remaining 6% of victims being adult males. Females exhibited more cannibalism than males, but this was only partially explained by their larger body size, suggesting greater energetic requirements of reproduction likely play a role as well. We found no evidence that dispersal‐limited environments had a lower prevalence of cannibalism, but prevalence was greater in populations with higher conspecific densities, suggesting that more intense resource competition drives cannibalistic behavior. Supporting this conclusion, our mesocosm experiment revealed that cannibalism prevalence increased with higher conspecific density and lower resource levels but was not associated with juvenile density or strongly influenced by predation risk. We suggest that cannibalism in livebearing fishes is rare in the wild because preying on conspecifics is energetically costly and only becomes worth the effort when competition for other food is intense. Due to the artificially reduced cost of capturing conspecifics within confined spaces, cannibalism in captive settings can be much more frequent. |
| first_indexed | 2024-04-12T17:36:44Z |
| format | Article |
| id | doaj.art-6affc0cd274844e6bdbdaadebc5aff3d |
| institution | Directory Open Access Journal |
| issn | 2045-7758 |
| language | English |
| last_indexed | 2024-04-12T17:36:44Z |
| publishDate | 2022-05-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecology and Evolution |
| spelling | doaj.art-6affc0cd274844e6bdbdaadebc5aff3d2022-12-22T03:22:57ZengWileyEcology and Evolution2045-77582022-05-01125n/an/a10.1002/ece3.8872Resource competition explains rare cannibalism in the wild in livebearing fishesRüdiger Riesch0Márcio S. Araújo1Stuart Bumgarner2Caitlynn Filla3Laura Pennafort4Taylor R. Goins5Darlene Lucion6Amber M. Makowicz7Ryan A. Martin8Sara Pirroni9R. Brian Langerhans10Department of Biological Sciences Centre for Ecology, Evolution and Behaviour Royal Holloway University of London Egham UKInstituto de Biociências Universidade Estadual Paulista (UNESP) Rio Claro BrazilDepartment of Biological Sciences North Carolina State University Raleigh North Carolina USADepartment of Biological Sciences North Carolina State University Raleigh North Carolina USADepartment of Biological Sciences Centre for Ecology, Evolution and Behaviour Royal Holloway University of London Egham UKDepartment of Biological Sciences North Carolina State University Raleigh North Carolina USADepartment of Biological Sciences Centre for Ecology, Evolution and Behaviour Royal Holloway University of London Egham UKDepartment of Biological Sciences Florida State University Tallahassee Florida USADepartment of Biology Case Western Reserve University Cleveland Ohio USADepartment of Biological Sciences Centre for Ecology, Evolution and Behaviour Royal Holloway University of London Egham UKDepartment of Biological Sciences North Carolina State University Raleigh North Carolina USAAbstract Cannibalism, the act of preying on and consuming a conspecific, is taxonomically widespread, and putatively important in the wild, particularly in teleost fishes. Nonetheless, most studies of cannibalism in fishes have been performed in the laboratory. Here, we test four predictions for the evolution of cannibalism by conducting one of the largest assessments of cannibalism in the wild to date coupled with a mesocosm experiment. Focusing on mosquitofishes and guppies, we examined 17 species (11,946 individuals) across 189 populations in the wild, spanning both native and invasive ranges and including disparate types of habitats. We found cannibalism to be quite rare in the wild: most populations and species showed no evidence of cannibalism, and the prevalence of cannibalism was typically less than 5% within populations when it occurred. Most victims were juveniles (94%; only half of these appeared to have been newborn offspring), with the remaining 6% of victims being adult males. Females exhibited more cannibalism than males, but this was only partially explained by their larger body size, suggesting greater energetic requirements of reproduction likely play a role as well. We found no evidence that dispersal‐limited environments had a lower prevalence of cannibalism, but prevalence was greater in populations with higher conspecific densities, suggesting that more intense resource competition drives cannibalistic behavior. Supporting this conclusion, our mesocosm experiment revealed that cannibalism prevalence increased with higher conspecific density and lower resource levels but was not associated with juvenile density or strongly influenced by predation risk. We suggest that cannibalism in livebearing fishes is rare in the wild because preying on conspecifics is energetically costly and only becomes worth the effort when competition for other food is intense. Due to the artificially reduced cost of capturing conspecifics within confined spaces, cannibalism in captive settings can be much more frequent.https://doi.org/10.1002/ece3.8872Gambusiaintraspecific competitionoptimal foraging theoryPoecilia reticulatapopulation densitysize difference |
| spellingShingle | Rüdiger Riesch Márcio S. Araújo Stuart Bumgarner Caitlynn Filla Laura Pennafort Taylor R. Goins Darlene Lucion Amber M. Makowicz Ryan A. Martin Sara Pirroni R. Brian Langerhans Resource competition explains rare cannibalism in the wild in livebearing fishes Ecology and Evolution Gambusia intraspecific competition optimal foraging theory Poecilia reticulata population density size difference |
| title | Resource competition explains rare cannibalism in the wild in livebearing fishes |
| title_full | Resource competition explains rare cannibalism in the wild in livebearing fishes |
| title_fullStr | Resource competition explains rare cannibalism in the wild in livebearing fishes |
| title_full_unstemmed | Resource competition explains rare cannibalism in the wild in livebearing fishes |
| title_short | Resource competition explains rare cannibalism in the wild in livebearing fishes |
| title_sort | resource competition explains rare cannibalism in the wild in livebearing fishes |
| topic | Gambusia intraspecific competition optimal foraging theory Poecilia reticulata population density size difference |
| url | https://doi.org/10.1002/ece3.8872 |
| work_keys_str_mv | AT rudigerriesch resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT marciosaraujo resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT stuartbumgarner resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT caitlynnfilla resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT laurapennafort resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT taylorrgoins resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT darlenelucion resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT ambermmakowicz resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT ryanamartin resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT sarapirroni resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes AT rbrianlangerhans resourcecompetitionexplainsrarecannibalisminthewildinlivebearingfishes |