Data for Body size matters for mate choice of the paradise fish
Description
In nature, animals of varying body sizes exhibit differences in genetics, growth rates, and resource-holding capacities. Numerous species display size-assortative mating patterns, which, according to matching theory, stem from mutual preferences for larger partners among both sexes. Although mate choice has been extensively studied in various animals (e.g., mammals and reptiles), some knowledge gaps remain regarding the role of morphological traits such as body size and the underlying behavioral mechanisms in fish. Here, our study investigates mate choice and same-sex behavior in the paradise fish (Macropodus opercularis). we have employed a male-male behavioural preference testing as a control measure to verify whether the outcome of this binary choice is associated with social preference Our findings indicate that female paradise fish consistently prefer larger individuals in both same-sex and opposite-sex encounters, regardless of their own body size. In contrast, male paradise fish exhibit a preference for smaller individuals in both types of encounters. Furthermore, the general activity levels of paradise fish, including swimming speed and percentage time spent on moving, do not appear to influence mate choice outcomes. These results provide evidence that larger body size may confer an advantage in mate choice for female paradise fish.
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Steps to reproduce
Initially, we employed a generalized linear model to explore the impacts of focal fish sex (i.e., focal male or female), stimulus fish size (i.e., small or large), and sex combination (i.e., different sex or same sex) on mate choice and same-sex preference behaviors in the paradise fish. In this model, focal fish sex (i.e., focal male or female), stimulus fish size (i.e., small or large), and sex combination (i.e., different sex or same sex) were used as fixed effects, while the percentage of time spent in the selected area was set as the dependent variable. The activity level (i.e., individual swimming speed and PTM) was incorporated as random effects. If the model indicated significant differences either among or within treatments, independent T-tests were conducted within a stimulus fish size treatment to compare the inter- or intra-treatment differences. Moreover, to delve deeper into the mate choice and same-sex preference behaviors of the paradise fish, we evaluated the strength of preference (SOP) between partners under different treatments (e.g., focal fish sex, stimulus fish size, and sex combination)
Institutions
- Chongqing Normal UniversityChongqing, Chongqing