Reproductive Mode and Conflict Shape the Evolution of Male Attributes and Rate of Speciation in the Fish Family Poeciliidae

Sexual conflict is caused by differences between the sexes in how fitness is maximized. These differences are shaped by the discrepancy in the investment in gametes, how mates are chosen and how embryos and young are provided for. Fish in the family Poeciliidae vary from completely provisioning eggs before they are fertilized to providing virtually all resources after fertilization via the functional equivalent of a mammalian placenta. This shift in when females provision their young relative to when an egg is fertilized is predicted to cause a fundamental change in when and how sexual conflict is manifested. If eggs are provisioned before fertilization, there should be strong selection for females to choose with whom they mate. Maternal provisioning after fertilization should promote a shift to post-copulatory mate choice. The evolution of maternal provisioning may in turn have cascading effects on the evolution of diverse features of the biology of these fish because of this shift in when mates are chosen. Here we summarize what these consequences are and show that the evolution of maternal provisioning is indeed associated with and appears to govern the evolution of male traits associated with sexual selection. The evolution of placentas and associated conflict does not cause accelerated speciation, contrary to predictions. Accelerated speciation rate is instead correlated with the evolution of male traits associated with sexual selection, which implies a more prominent role of pre-copulatory reproductive isolation in causing speciation in this family.

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Extremely rapid development and early reproduction reduces sexual selection in D. melanogaster populations.

10.1101/2021.04.09.439133 ◽

2021 ◽

Author(s):

Avani Mital ◽

Manaswini Sarangi ◽

Bodhisatta Nandy ◽

Neha Pandey ◽

Amitabh Joshi

Keyword(s):

Sexual Selection ◽

Sexual Conflict ◽

Rapid Development ◽

Fertilization Success ◽

Direct Selection ◽

Reproductive Competition ◽

Short Development Time ◽

Low Levels ◽

Selection For

The role of sexual selection in mediating levels of sexual conflict has been demonstrated in a number of experimental evolution studies on Drosophila sp. where the level of competition among males for fertilization success was under direct selection. Here we report that selection for a short development time and early age at reproduction can lead to inadvertent changes in levels of sexual selection in D. melanogaster populations, affecting reproductive competition experienced by males. We demonstrate that faster developing and early reproducing populations showed very low levels of mating in their lifetime (likely being monogamous), low courtship levels, shorter copulation duration and longer maturation time, compared to their ancestral controls. We discuss these results in light of the previously demonstrated reduction of sexual conflict in these populations.

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Losses of female song with changes from tropical to temperate breeding in the New World blackbirds

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2008.1626 ◽

2009 ◽

Vol 276 (1664) ◽

pp. 1971-1980 ◽

Cited By ~ 76

Author(s):

J. Jordan Price ◽

Scott M. Lanyon ◽

Kevin E. Omland

Keyword(s):

Sexual Selection ◽

New World ◽

Female Song ◽

Complex Song ◽

Evolutionary Changes ◽

Apparent Relationship ◽

Song Production ◽

Selection For ◽

The Tropics

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.

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The Potential Role of Sexual Conflict and Sexual Selection in Shaping the Genomic Distribution of Mito-nuclear Genes

Genome Biology and Evolution ◽

10.1093/gbe/evu063 ◽

2014 ◽

Vol 6 (5) ◽

pp. 1096-1104 ◽

Cited By ~ 23

Author(s):

R. Dean ◽

F. Zimmer ◽

J. E. Mank

Keyword(s):

Sexual Selection ◽

Sexual Conflict ◽

Potential Role ◽

Nuclear Genes ◽

Genomic Distribution

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Ecology and the diversification of reproductive strategies in viviparous fishes

10.1101/442830 ◽

2018 ◽

Author(s):

Michael Tobler ◽

Zachary Culumber

Keyword(s):

Sexual Selection ◽

Life History ◽

Reproductive Strategies ◽

Life History Evolution ◽

Evolutionary Transitions ◽

Cascading Effects ◽

High Resource ◽

Correlated Patterns ◽

Maternal Provisioning ◽

Provisioning Strategies

AbstractShifts in life history evolution can potentiate sexual selection and speciation. However, we rarely understand the causative links between correlated patterns of diversification or the tipping points that initiate changes with cascading effects. We investigated livebearing fishes with repeated transitions from pre- (lecithotrophy) to post-fertilization maternal provisioning (matrotrophy) to identify the potential ecological drivers of evolutionary transitions in life history. Phylogenetic comparative analyses across 94 species revealed that bi-directional evolution along the lecithotrophy-matrotrophy continuum is correlated with ecology, supporting adaptive hypotheses of life history diversification. Consistent with theory, matrotrophy was associated with high resource availability and low competition. Our results suggest that ecological sources of selection contribute to the diversification of female provisioning strategies in livebearing fishes, which have been associated with macroevolutionary patterns of sexual selection and speciation.

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Sexual size dimorphism and sexual selection in artiodactyls

Behavioral Ecology ◽

10.1093/beheco/araa017 ◽

2020 ◽

Vol 31 (3) ◽

pp. 792-797

Author(s):

Marcelo H Cassini

Keyword(s):

Sexual Selection ◽

Sexual Dimorphism ◽

Group Size ◽

Sexual Size Dimorphism ◽

Alternative Hypothesis ◽

Mammalian Species ◽

Generalized Least Squares ◽

Size Dimorphism ◽

Selection For

Abstract Sexual size dimorphism is biased toward males in most mammalian species. The most common explanation is precopulatory intramale sexual selection. Large males win fights and mate more frequently. In artiodactyls, previous tests of this hypothesis consisted of interspecific correlations of sexual dimorphism with group size as a surrogate for the intensity of sexual selection (Is). However, group size is not a proper measure of sexual selection for several reasons as is largely recognized in other mammalian taxa. I conducted an interspecific test on the role of sexual selection in the evolution of sexual dimorphism using the variance in genetic paternity as a proxy for the Is. I reviewed the literature and found 17 studies that allowed estimating Is= V/(W2), where V and W are the variance and mean number of offspring per male, respectively. A phylogenetic generalized least squares analysis indicated that dimorphism (Wm/Wf) showed a significant positive regression with the intensity of sexual selection but not group size (multiple r2= 0.40; F3,17= 12.78, P = 0.002). This result suggests that sexual selection may have played a role in the evolution of sexual size dimorphism in Artiodactyla. An alternative hypothesis based on natural selection is discussed.

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Shoes for Children: A Review

PEDIATRICS ◽

10.1542/peds.88.2.371 ◽

1991 ◽

Vol 88 (2) ◽

pp. 371-375

Author(s):

Lynn T. Staheli

Keyword(s):

Load Distribution ◽

Medical Profession ◽

Primary Role ◽

Shock Absorption ◽

The Family ◽

Selection For ◽

Foot Development

1. Optimum foot development occurs in the barefoot environment. 2. The primary role of shoes is to protect the foot from injury and infection. 3. Stiff and compressive footwear may cause deformity, weakness, and loss of mobility. 4. The term "corrective shoes" is a misnomer. 5. Shock absorption, load distribution, and elevation are valid indications for shoe modifications. 6. Shoe selection for children should be based on the barefoot model. 7. Physicians should avoid and discourage the commercialization and "media"-ization of footwear. Merchandizing of the "corrective shoe" is harmful to the child, expensive for the family, and a discredit to the medical profession.

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Animal personalities and their implications for complex signaling

Current Zoology ◽

10.1093/czoolo/60.3.381 ◽

2014 ◽

Vol 60 (3) ◽

pp. 381-386 ◽

Cited By ~ 5

Author(s):

Nicholas Dirienzo ◽

Ann V Hedrick

Keyword(s):

Sexual Selection ◽

Behavioral Ecology ◽

Ecological Processes ◽

Signaling Systems ◽

Signaling Complex ◽

Selection For ◽

Complex Signaling ◽

Animal Personalities ◽

Signaling Interactions

Abstract Animal personalities have been a major focus of behavioral ecology over the past decade. Consistent individual differences in behavior have been found across taxa, and have been shown to influence a range of ecological processes. The role of personalities in sexual selection has been considered, and examples exist that show selection for personality traits with both assortative and disassortative mating patterns between personality types. One overlooked aspect of the personality and sexual selection literature is the potential for personality-signaling interactions, specifically with complex signaling. Complex signaling is a diverse topic in itself, and in short, consists of multiple signals within one or more modalities that interact to elicit a receiver response. Research into complex signaling has been thorough, although at times studies discover complex signaling systems that fail to fit into one of the existing hypotheses in the literature. Here, we argue that personalities may interact with complex signaling, which should be considered by researchers of both personality and sexual selection and communication. We describe several ways in which personality-complex signaling interactions could affect both the signaler and receiver, and the way in which they may drive personality-specific signals as well as receiver preferences. Finally, we discuss how considering personality in complex signaling studies may inform theory as well as improve the ability of researchers to accurately describe its function.

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