scholarly journals Beyond sex allocation: the role of mating systems in sexual selection in parasitoid wasps

2014 ◽  
Vol 90 (2) ◽  
pp. 599-627 ◽  
Author(s):  
Rebecca A. Boulton ◽  
Laura A. Collins ◽  
David M. Shuker
2013 ◽  
Vol 368 (1613) ◽  
pp. 20120052 ◽  
Author(s):  
Lukas Schärer ◽  
Ido Pen

Sex allocation theory predicts the optimal allocation to male and female reproduction in sexual organisms. In animals, most work on sex allocation has focused on species with separate sexes and our understanding of simultaneous hermaphrodites is patchier. Recent theory predicts that sex allocation in simultaneous hermaphrodites should strongly be affected by post-copulatory sexual selection, while the role of pre-copulatory sexual selection is much less clear. Here, we review sex allocation and sexual selection theory for simultaneous hermaphrodites, and identify several strong and potentially unwarranted assumptions. We then present a model that treats allocation to sexually selected traits as components of sex allocation and explore patterns of allocation when some of these assumptions are relaxed. For example, when investment into a male sexually selected trait leads to skews in sperm competition, causing local sperm competition, this is expected to lead to a reduced allocation to sperm production. We conclude that understanding the evolution of sex allocation in simultaneous hermaphrodites requires detailed knowledge of the different sexual selection processes and their relative importance. However, little is currently known quantitatively about sexual selection in simultaneous hermaphrodites, about what the underlying traits are, and about what drives and constrains their evolution. Future work should therefore aim at quantifying sexual selection and identifying the underlying traits along the pre- to post-copulatory axis.


Author(s):  
Rachel Olzer ◽  
Rebecca L. Ehrlich ◽  
Justa L. Heinen-Kay ◽  
Jessie Tanner ◽  
Marlene Zuk

Sex and reproduction lie at the heart of studies of insect behavior. We begin by providing a brief overview of insect anatomy and physiology, followed by an introduction to the overarching themes of parental investment, sexual selection, and mating systems. We then take a sequential approach to illustrate the diversity of phenomena and concepts behind insect reproductive behavior from pre-copulatory mate signalling through copulatory sperm transfer, mating positions, and sexual conflict, to post-copulatory sperm competition, and cryptic female choice. We provide an overview of the evolutionary mechanisms driving reproductive behavior. These events are linked by the economic defendability of mates or resources, and how these are allocated in each sex. Under the framework of economic defendability, the reader can better understand how sexual antagonistic behaviors arise as the result of competing optimal fitness strategies between males and females.


2018 ◽  
Vol 285 (1883) ◽  
pp. 20180836 ◽  
Author(s):  
Jukka Kekäläinen ◽  
Jonathan P. Evans

‘Sperm competition’—where ejaculates from two or more males compete for fertilization—and ‘cryptic female choice’—where females bias this contest to suit their reproductive interests—are now part of the everyday lexicon of sexual selection. Yet the physiological processes that underlie these post-ejaculatory episodes of sexual selection remain largely enigmatic. In this review, we focus on a range of post-ejaculatory cellular- and molecular-level processes, known to be fundamental for fertilization across most (if not all) sexually reproducing species, and point to their putative role in facilitating sexual selection at the level of the cells and gametes, called ‘gamete-mediated mate choice’ (GMMC). In this way, we collate accumulated evidence for GMMC across different mating systems, and emphasize the evolutionary significance of such non-random interactions among gametes. Our overall aim in this review is to build a more inclusive view of sexual selection by showing that mate choice often acts in more nuanced ways than has traditionally been assumed. We also aim to bridge the conceptual divide between proximal mechanisms of reproduction, and adaptive explanations for patterns of non-random sperm–egg interactions that are emerging across an increasingly diverse array of taxa.


1990 ◽  
Vol 40 (2) ◽  
pp. 367-373 ◽  
Author(s):  
J. David Ligon ◽  
Randy Thornhill ◽  
Marlene Zuk ◽  
Kristine Johnson

2009 ◽  
Vol 276 (1664) ◽  
pp. 1971-1980 ◽  
Author(s):  
J. Jordan Price ◽  
Scott M. Lanyon ◽  
Kevin E. Omland

Birds in which both sexes produce complex songs are thought to be more common in the tropics than in temperate areas, where typically only males sing. Yet the role of phylogeny in this apparent relationship between female song and latitude has never been examined. Here, we reconstruct evolutionary changes in female song and breeding latitude in the New World blackbirds (Icteridae), a family with both temperate and tropical representatives. We provide strong evidence that members of this group have moved repeatedly from tropical to temperate breeding ranges and, furthermore, that these range shifts were associated with losses of female song more often than expected by chance. This historical perspective suggests that male-biased song production in many temperate species is the result not of sexual selection for complex song in males but of selection against such songs in females. Our results provide new insights into the differences we see today between tropical and temperate songbirds, and suggest that the role of sexual selection in the evolution of bird song might not be as simple as we think.


2018 ◽  
Author(s):  
Piret Avila ◽  
Lutz Fromhage ◽  
Laurent Lehmann

AbstractModels of sex allocation conflict are central to evolutionary biology but have mostly assumed static decisions, where resource allocation strategies are constant over colony lifespan. Here, we develop a model to study how the evolution of dynamic resource allocation strategies is affected by the queen-worker conflict in annual eusocial insects. We demonstrate that the time of dispersal of sexuals affects the sex allocation ratio through sexual selection on males. Furthermore, our model provides three predictions that depart from established results of classic static allocation models. First, we find that the queen wins the sex allocation conflict, while the workers determine the maximum colony size and colony productivity. Second, male-biased sex allocation and protandry evolve if sexuals disperse directly after eclosion. Third, when workers are more related to new queens, then the proportional investment into queens is expected to be lower, which results from the interacting effect of sexual selection (selecting for protandry) and sex allocation conflict (selecting for earlier switch to producing sexuals). Overall, we find that colony ontogeny crucially affects the outcome of sex-allocation conflict because of the evolution of distinct colony growth phases, which decouples how queens and workers affect allocation decisions and can result in asymmetric control.


Author(s):  
Lee Cronk ◽  
Beth L. Leech

This chapter examines the concept of adaptation and how it is applied (and sometimes misapplied) to cooperation. It starts with George C. Williams's idea that adaptation is a “special and onerous concept that should be used only where it is really necessary,” which he articulated in Adaptation and Natural Selection. It then considers different levels of explanation that help clarify the notion of adaptation, fortuitous benefits and by-product mutualism in relation to adaptation, and the link between adaptation and natural, artificial, social, and sexual selection. It also explores how phylogeny constrains natural selection, the ways that adaptations solve specific problems found in specific environments, and how adaptation influences judgment. Finally, it analyzes the role of culture and language in adaptation and evolutionary explanations of morality.


Author(s):  
Michael D. Jennions ◽  
Christopher J. Lortie ◽  
Julia Koricheva

This chapter describes nine case studies that illustrate how meta-analysis has contributed to theoretical developments in basic research in ecology and evolution. The main research topics cover are maintenance of biodiversity (Case 1); sexual selection (mate choice/fighting behavior) (cases 2, 8, 9); sex ratio theory (Case 3); allometric scaling (Case 4); the invasiveness of exotic plants (Case 5); seed size and plant abundance (Case 6); and the role of competition and predation in structuring communities (Case 7). It is hoped that these case studies will resonate with the reader and provide “templates” for ways to conduct comparable tests on analogous controversies in their own fields of research.


Sign in / Sign up

Export Citation Format

Share Document