Adult nutrition, but not inbreeding, affects male primary sexual traits in the leaf‐footed cactus bug Narnia femorata (Hemiptera: Coreidae)

Abstract

Adverse conditions may be the norm rather than the exception in natural populations. Many populations experience poor nutrition on a seasonal basis. Further, brief interludes of inbreeding can be common as population density fluctuates and because of habitat fragmentation. Here, we investigated the effects of poor nutrition and inbreeding on traits that can be very important to reproductive success and fitness in males: testes mass, sperm concentration, and sperm viability. Our study species was Narnia femorata, a species introduced to north‐central Florida in the 1950s. This species encounters regular, seasonal changes in diet that can have profound phenotypic effects on morphology and behavior. We generated inbred and outbred individuals through a single generation of full‐sibling mating or outcrossing, respectively. All juveniles were provided a natural, high‐quality diet of Opuntia humifusa cactus cladode with fruit until they reached adulthood. New adult males were put on a high‐ or low‐quality diet for at least 21 days before measurements were taken. As expected, the low‐quality diet led to significantly decreased testes mass in both inbred and outbred males, although there were surprisingly no detectable effects on sperm traits. We did not find evidence that inbreeding affected testes mass, sperm concentration, and sperm viability. Our results highlight the immediate and overwhelming effects of nutrition on testes mass, while suggesting that a single generation of inbreeding might not be detrimental for primary sexual traits in this particular population.

Seasonal Effects on the Population, Morphology and Reproductive Behavior of Narnia femorata (Hemiptera: Coreidae)

“…The extent to which these changes are directly related to host plant phenology, temperature, social environment, or other factors cannot be concluded from this single study. However, many results mirror findings from the laboratory [4,8,33,34,35,36,43,45,57]. Together, the existing work makes a powerful case that host plant phenology can alter growth and development in these insects, and that these phenomena extend to real-world settings.…”

“…Temperature, density, or other environmental factors may add to or interact with effects of nutrition on these populations of insects and warrant further study. Finally, thepresence of some red ripe fruit, particularly at the Agricultural Site, should be a boon for insects fortunate enough to develop on this high-quality resource [8,35,36,45,57]. It may be that these well-nourished individuals existed, but that they were outnumbered by those stranded for part of development without cactus fruit at all.…”

A study of the transit amplification divisions during spermatogenesis in Oncopetus fasciatus to assess plasticity in sperm numbers or sperm viability under different diets

“…Research on reproductive costs for males has focused on mate searching, courtship, and malemale competition under different environments, both social and nutritional environments (Flatt & Heyland, 2011;Hunt et al, 2004;Scharf, Peter, & Martin, 2013;Shuker & Simmons, 2014). It is now clear, however, that the sperm production represents a significant cost to males and researchers are exploring phenotypic plasticity in sperm numbers and quality under variable social and nutritional environments (Bunning et al, 2015;Dávila & Aron, 2017;Joseph, Sasson, Allen, Somjee, & Miller, 2016;Moatt, Dytham, & Thom, 2014). Drosophila melanogaster males exposed to the odor of a rival male store both more sperm and a greater proportion of live sperm in their seminal vesicles (Moatt et al, 2014).…”

“…Drosophila melanogaster males exposed to the odor of a rival male store both more sperm and a greater proportion of live sperm in their seminal vesicles (Moatt et al, 2014). High-quality nutrition, on the other hand, appears to promote increased sperm numbers, but does not impact sperm quality in cockroaches (Bunning et al, 2015), leaf-footed bugs (Joseph et al, 2016), or ants (Dávila & Aron, 2017).…”

Broadening the voice of science: Promoting scientific communication in the undergraduate classroom

“…Further, we revisited and reinforced student understanding of ecology and evolutionary biology to help them gain deeper context for their ongoing laboratory research projects (e.g. Cirino & Miller, ; Emberts, St Mary, & Miller, ; Joseph, Sasson, Allen, Somjee, & Miller, ; Miller, McDonald, & Moore, ). Activities specifically focused on science oral communication involved (i) the presentation of primary scientific literature to peers, (ii) the development of a research monologue for the public, and (iii) the construction and presentation of a technical poster based on their current undergraduate research.…”