An Evolutionary Ecological Approach to Sex Allocation and Sex Determination in Crustaceans

2020 ◽  
pp. 177-196
Author(s):  
Kota Sawada ◽  
Sachi Yamaguchi
Keyword(s):  
Sex Determination ◽  
Sex Allocation ◽  
Evolutionary Ecology ◽  
Empirical Studies ◽  
Ecological Approach ◽  
Sexual Strategies ◽  
Sexual Systems ◽  
Mating Group ◽  
Simultaneous Hermaphrodites ◽  
Allocation Strategies

This chapter reviews sex determination and sex allocation strategies among crustaceans with different sexual systems (gonochorism, sequential and simultaneous hermaphroditism, and androdioecy), from the perspective of evolutionary ecology. The discussion includes genetic, environmental, and cytoplasmic sex determination in free-living and parasitic crustaceans, timing and frequency of sex change especially in partial protandry, the effects of mating group size on resource allocation by simultaneous hermaphrodites, and sex ratio and determination in androdioecious crustaceans. The fascinating diversity of crustacean reproduction stimulated theoretical biologists to construct models to explain them, and empirical biologists attempted to test hypotheses derived from those models. This review clearly shows that the interaction between theoretical and empirical studies has facilitated understanding of the evolutionary conditions of diverse sexual strategies among crustaceans. Since sexual strategies often interact with other aspects of adaptive strategies such as life history, integrating different aspects into both theoretical and empirical studies will provide further understandings into crustacean sexual systems. In addition, the authors point out the potential of phylogenetic comparative analyses using natural history data as a tool to understand the tempo and mode of evolution of sex allocation strategies.

Mixed sex allocation strategies in a polytocous mammal, the house mouse (Mus musculus)

2011 ◽  
Vol 65 (12) ◽  
pp. 2209-2217 ◽  
Author(s):  
Adam Dušek ◽  
Luděk Bartoš ◽  
František Sedláček
Keyword(s):  
House Mouse ◽  
Mus Musculus ◽  
Sex Allocation ◽  
Allocation Strategies ◽  
Polytocous Mammal

scholarly journals Sex allocation conflict and sexual selection throughout the lifespan of eusocial colonies

2018 ◽  
Author(s):  
Piret Avila ◽  
Lutz Fromhage ◽  
Laurent Lehmann
Keyword(s):  
Resource Allocation ◽  
Sexual Selection ◽  
Evolutionary Biology ◽  
Sex Allocation ◽  
Colony Growth ◽  
Eusocial Insects ◽  
Dynamic Resource ◽  
Colony Ontogeny ◽  
Allocation Decisions ◽  
Allocation Strategies

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.

Team Effectiveness in Virtual Environments

2008 ◽  
pp. 1498-1515
Author(s):  
Pnina Shachaf ◽  
N. Hara
Keyword(s):  
Learning Environments ◽  
Team Effectiveness ◽  
Empirical Studies ◽  
External Environment ◽  
Virtual Team ◽  
Ecological Approach ◽  
Internal Environment ◽  
Normative Model ◽  
Process Output ◽  
Pedagogical Approaches

This chapter attempts to address the need for more research on virtual team effectiveness and outlines an ecological theoretical framework that is applicable to virtual learning environments (VLE).  Prior empirical studies on virtual team effectiveness used frameworks of traditional team effectiveness and mainly followed Hackman’s normative model (input-process-output). We propose an ecological approach for virtual team effectiveness that accounts for team boundaries management, technologyuse, and external environment in VLE, properties which were previously either nonexistent or contextual.   The ecological framework suggests that three components — external environment, internal environment, and boundary management — reciprocally interact with effectiveness.   The significance of the proposed framework is a holistic perspective that takes into account the complexity of the external and internal environment of the team. Furthermore, we address the needs for new pedagogical approaches in VLE.

scholarly journals Different effects of mating group size as male and as female on sex allocation in a simultaneous hermaphrodite

2020 ◽  
Vol 10 (5) ◽  
pp. 2492-2498
Author(s):  
Masami M. Tamechika ◽  
Kohei Matsuno ◽  
Satoshi Wada ◽  
Yoichi Yusa
Keyword(s):  
Group Size ◽  
Sex Allocation ◽  
Simultaneous Hermaphrodite ◽  
Mating Group

What Fig Wasp Sex Ratios May or May Not Tell Us about Sex Allocation Strategies

Oikos ◽  
1999 ◽  
Vol 87 (3) ◽  
pp. 520 ◽  
Author(s):  
Prarthana Kathuria ◽  
Jaco M. Greeff ◽  
Steve G. Compton ◽  
K. N. Ganeshaiah
Keyword(s):  
Sex Allocation ◽  
Sex Ratios ◽  
Fig Wasp ◽  
Allocation Strategies

scholarly journals Sex allocation theory reveals a hidden cost of neonicotinoid exposure in a parasitoid wasp

2015 ◽  
Vol 282 (1807) ◽  
pp. 20150389 ◽  
Author(s):  
Penelope R. Whitehorn ◽  
Nicola Cook ◽  
Charlotte V. Blackburn ◽  
Sophie M. Gill ◽  
Jade Green ◽  
...  
Keyword(s):  
Sex Allocation ◽  
Evolutionary Ecology ◽  
Parasitoid Wasp ◽  
Reproductive Behaviour ◽  
Fitness Costs ◽  
Offspring Sex ◽  
Hidden Cost ◽  
Sex Allocation Theory ◽  
First Time ◽  
Fecundity Reduction

Sex allocation theory has proved to be one the most successful theories in evolutionary ecology. However, its role in more applied aspects of ecology has been limited. Here we show how sex allocation theory helps uncover an otherwise hidden cost of neonicotinoid exposure in the parasitoid wasp Nasonia vitripennis . Female N. vitripennis allocate the sex of their offspring in line with Local Mate Competition (LMC) theory. Neonicotinoids are an economically important class of insecticides, but their deployment remains controversial, with evidence linking them to the decline of beneficial species. We demonstrate for the first time to our knowledge, that neonicotinoids disrupt the crucial reproductive behaviour of facultative sex allocation at sub-lethal, field-relevant doses in N. vitripennis . The quantitative predictions we can make from LMC theory show that females exposed to neonicotinoids are less able to allocate sex optimally and that this failure imposes a significant fitness cost. Our work highlights that understanding the ecological consequences of neonicotinoid deployment requires not just measures of mortality or even fecundity reduction among non-target species, but also measures that capture broader fitness costs, in this case offspring sex allocation. Our work also highlights new avenues for exploring how females obtain information when allocating sex under LMC.

Sign in / Sign up

Export Citation Format

Share Document