Behaviors may enhance fitness in some situations while being detrimental in others. Linked behaviors (behavioral syndromes) may be central to understanding the maintenance of behavioral variability in natural populations. The spillover hypothesis of premating sexual cannibalism by females explains genetically determined female aggression towards both prey and males: growth to a larger size translates into higher fecundity, but at the risk of insufficient sperm acquisition. Here, we use an individual-based model to determine the ecological scenarios under which this spillover strategy is more likely to evolve over a strategy in which females attack approaching males only once the female has previously secured sperm. We found that a classic spillover strategy could never prevail. However, a more realistic early-spillover strategy, in which females become adults earlier in addition to reaching a larger size, could be maintained in some ecological scenarios and even invade a population of females following the other strategy. We also found under some ecological scenarios that both behavioral types coexist through frequency-dependent selection. Additionally, using data from the spider Lycosa hispanica, we provide strong support for the prediction that the two strategies may coexist in the wild. Our results clarify how animal personalities evolve and are maintained in nature.
Digital Object Identifier (DOI)
This work was partially funded by the Spanish Ministry of Science and Innovation grant CGL2004-03153 to J.M.-L.
Supplementary materials are available online at http://www.mdpi.com/2079-7737/9/9/241/s1. They are also available for download as the additional file listed at the end of this record.
Externally hosted supplementary file 1
- Link: http://www.eeza.csic.es/foodweb/Simulators_FWEE.html
- Description: Page with the MATLAB code
Moya-Laraño, Jordi; Rabaneda-Bueno, Rubén; Morrison, Emily; and Crowley, Phillip H., "Model and Data Concur and Explain the Coexistence of Two Very Distinct Animal Behavioral Types" (2020). Biology Faculty Publications. 195.