Numbers, neighbors, and hungry predators: What makes chemically defended aposematic prey susceptible to predation?
Abstract Many chemically defended aposematic species are characterized by relatively low toxin levels, which enables predators to include them in their diets under certain circumstances. Knowledge of the conditions governing the survival of such prey animals—especially in the context of the co‐occur...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2020-12-01
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| Series: | Ecology and Evolution |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ece3.6956 |
| _version_ | 1819098662188351488 |
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| author | Jan M. Kaczmarek Mikołaj Kaczmarski Jan Mazurkiewicz Janusz Kloskowski |
| author_facet | Jan M. Kaczmarek Mikołaj Kaczmarski Jan Mazurkiewicz Janusz Kloskowski |
| author_sort | Jan M. Kaczmarek |
| collection | DOAJ |
| description | Abstract Many chemically defended aposematic species are characterized by relatively low toxin levels, which enables predators to include them in their diets under certain circumstances. Knowledge of the conditions governing the survival of such prey animals—especially in the context of the co‐occurrence of similar but undefended prey, which may result in mimicry‐like interactions—is crucial for understanding the initial evolution of aposematism. In a one‐month outdoor experiment using fish (the common carp Cyprinus carpio) as predators, we examined the survival of moderately defended aposematic tadpole prey (the European common toad Bufo bufo) with varying absolute densities in single‐species prey systems or varying relative densities in two‐species prey systems containing morphologically similar but undefended prey (the European common frog Rana temporaria). The density effects were investigated in conjunction with the hunger levels of the predator, which were manipulated by means of the addition of alternative (nontadpole) food. The survival of the B. bufo tadpoles was promoted by increasing their absolute density in the single‐species prey systems, increasing their relative density in the two‐species prey systems, and providing ample alternative food for the predator. Hungry predators eliminated all R. temporaria individuals regardless of their proportion in the prey community; in treatments with ample alternative food, high relative B. bufo density supported R. temporaria survival. The results demonstrated that moderately defended prey did benefit from high population densities (both absolute and relative), even under long‐term predation pressure. However, the physiological state of the predator was a crucial factor in the survival of moderately defended prey. While the availability of alternative prey in general should promote the spread and maintenance of aposematism, the results indicated that the resemblance between the co‐occurring defended and undefended prey may impose mortality costs on the defended model species, even in the absence of actual mimicry. |
| first_indexed | 2024-12-22T00:34:33Z |
| format | Article |
| id | doaj.art-cc9b8d6be0e144e29e42f704f917393e |
| institution | Directory Open Access Journal |
| issn | 2045-7758 |
| language | English |
| last_indexed | 2024-12-22T00:34:33Z |
| publishDate | 2020-12-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecology and Evolution |
| spelling | doaj.art-cc9b8d6be0e144e29e42f704f917393e2022-12-21T18:44:51ZengWileyEcology and Evolution2045-77582020-12-011024137051371610.1002/ece3.6956Numbers, neighbors, and hungry predators: What makes chemically defended aposematic prey susceptible to predation?Jan M. Kaczmarek0Mikołaj Kaczmarski1Jan Mazurkiewicz2Janusz Kloskowski3Department of Zoology Poznań University of Life Sciences Poznań PolandDepartment of Zoology Poznań University of Life Sciences Poznań PolandDepartment of Inland Fisheries and Aquaculture Poznań University of Life Sciences Poznań PolandDepartment of Zoology Poznań University of Life Sciences Poznań PolandAbstract Many chemically defended aposematic species are characterized by relatively low toxin levels, which enables predators to include them in their diets under certain circumstances. Knowledge of the conditions governing the survival of such prey animals—especially in the context of the co‐occurrence of similar but undefended prey, which may result in mimicry‐like interactions—is crucial for understanding the initial evolution of aposematism. In a one‐month outdoor experiment using fish (the common carp Cyprinus carpio) as predators, we examined the survival of moderately defended aposematic tadpole prey (the European common toad Bufo bufo) with varying absolute densities in single‐species prey systems or varying relative densities in two‐species prey systems containing morphologically similar but undefended prey (the European common frog Rana temporaria). The density effects were investigated in conjunction with the hunger levels of the predator, which were manipulated by means of the addition of alternative (nontadpole) food. The survival of the B. bufo tadpoles was promoted by increasing their absolute density in the single‐species prey systems, increasing their relative density in the two‐species prey systems, and providing ample alternative food for the predator. Hungry predators eliminated all R. temporaria individuals regardless of their proportion in the prey community; in treatments with ample alternative food, high relative B. bufo density supported R. temporaria survival. The results demonstrated that moderately defended prey did benefit from high population densities (both absolute and relative), even under long‐term predation pressure. However, the physiological state of the predator was a crucial factor in the survival of moderately defended prey. While the availability of alternative prey in general should promote the spread and maintenance of aposematism, the results indicated that the resemblance between the co‐occurring defended and undefended prey may impose mortality costs on the defended model species, even in the absence of actual mimicry.https://doi.org/10.1002/ece3.6956amphibianaposematismassociational effectsmimicrypredator hungertadpole |
| spellingShingle | Jan M. Kaczmarek Mikołaj Kaczmarski Jan Mazurkiewicz Janusz Kloskowski Numbers, neighbors, and hungry predators: What makes chemically defended aposematic prey susceptible to predation? Ecology and Evolution amphibian aposematism associational effects mimicry predator hunger tadpole |
| title | Numbers, neighbors, and hungry predators: What makes chemically defended aposematic prey susceptible to predation? |
| title_full | Numbers, neighbors, and hungry predators: What makes chemically defended aposematic prey susceptible to predation? |
| title_fullStr | Numbers, neighbors, and hungry predators: What makes chemically defended aposematic prey susceptible to predation? |
| title_full_unstemmed | Numbers, neighbors, and hungry predators: What makes chemically defended aposematic prey susceptible to predation? |
| title_short | Numbers, neighbors, and hungry predators: What makes chemically defended aposematic prey susceptible to predation? |
| title_sort | numbers neighbors and hungry predators what makes chemically defended aposematic prey susceptible to predation |
| topic | amphibian aposematism associational effects mimicry predator hunger tadpole |
| url | https://doi.org/10.1002/ece3.6956 |
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