scholarly journals Nuclear arms races: experimental evolution for mating success in the mushroom-forming fungus Schizophyllum commune

2018 ◽  
Author(s):  
Bart P. S. Nieuwenhuis ◽  
Duur K. Aanen
Keyword(s):  
Sexual Selection ◽  
Mating Success ◽  
Experimental Evolution ◽  
Schizophyllum Commune ◽  
Spore Production ◽  
Pollen Competition ◽  
Male Reproductive Success ◽  
Competitive Fitness ◽  
Trade Offs ◽  
The One

SummaryWhen many gametes compete to fertilize a limited number of compatible gametes, sexual selection will favour traits that increase competitive success during mating. In animals and plants, sperm and pollen competition have yielded many interesting adaptations for improved mating success. In fungi, similar processes have not been shown directly yet. We test the hypothesis that sexual selection can increase competitive fitness during mating, using experimental evolution in the mushroom-forming fungus Schizophyllum commune (Basidiomycota). Mating in mushroom fungi occurs by donation of nuclei to a mycelium. These fertilizing ‘male’ nuclei migrate through the receiving ‘female’ mycelium. In our setup, an evolving population of nuclei was serially mated with a non-evolving female mycelium for 20 sexual generations. From the twelve tested evolved lines, four had increased and one had decreased fitness relative to an unevolved competitor. Even though only two of those five remained significant after correcting for multiple comparisons, for all five lines we found a correlation between the efficiency with which the female mycelium is accessed and fitness, providing additional circumstantial evidence for fitness change in those five lines. In two lines, fitness change was also accompanied by increased spore production. The one line with net reduced competitive fitness had increased spore production, but reduced fertilisation efficiency. We did not find trade-offs between male reproductive success and other fitness components. We compare these findings with examples of sperm and pollen competition and show that many similarities between these systems and nuclear competition in mushrooms exist.

scholarly journals Sexual selection gradients change over time in a simultaneous hermaphrodite

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Jeroen NA Hoffer ◽  
Janine Mariën ◽  
Jacintha Ellers ◽  
Joris M Koene
Keyword(s):  
Sexual Selection ◽  
Reproductive Success ◽  
Mating Success ◽  
Time Window ◽  
Time Frame ◽  
Male Reproductive Success ◽  
Simultaneous Hermaphrodite ◽  
Selection Gradients ◽  
Short Time Window ◽  
Over Time

Sexual selection is generally predicted to act more strongly on males than on females. The Darwin-Bateman paradigm predicts that this should also hold for hermaphrodites. However, measuring this strength of selection is less straightforward when both sexual functions are performed throughout the organism’s lifetime. Besides, quantifications of sexual selection are usually done during a short time window, while many animals store sperm and are long-lived. To explore whether the chosen time frame affects estimated measures of sexual selection, we recorded mating success and reproductive success over time, using a simultaneous hermaphrodite. Our results show that male sexual selection gradients are consistently positive. However, an individual’s female mating success seems to negatively affect its own male reproductive success, an effect that only becomes visible several weeks into the experiment, highlighting that the time frame is crucial for the quantification and interpretation of sexual selection measures, an insight that applies to any iteroparous mating system.

scholarly journals Can Sexual Selection Cause Divergence in Mating System-Related Floral Traits?

2019 ◽  
Author(s):  
Åsa Lankinen ◽  
Maria Strandh
Keyword(s):  
Sexual Selection ◽  
Mating System ◽  
Experimental Evolution ◽  
Seed Set ◽  
Pollen Competition ◽  
Floral Traits ◽  
Mixed Mating ◽  
Stigma Receptivity ◽  
Source Line ◽  
Outcrossing Species

AbstractPremise of the ResearchThe wide diversity of floral traits seen among plants is shaped by neutral and selective evolutionary processes. In outcrossing species, sexual selection from competing pollen donors is expected to be important for shaping mating system-related traits but empirical evidence is scarce. In a previous evaluation of experimental evolution lines crossed with either one or two pollen donors (monogamous, M, or polyandrous, P, lines) at early floral stages in mixed-mating Collinsia heterophylla (Plantaginaceae), P showed enhanced pollen competitive ability and reduced maternal seed set compared to M, in accordance with sexually antagonistic evolution of pollen. Here, we asked whether the presence of sexual selection during pollen competition affect mating system-related floral traits in the same lines.MethodologyWe compared flowering start, timing of anther-stigma contact (as an indication of timing of self-pollination), timing of stigma receptivity and first seed set between M and P, and with a source line, S (starting material). The former three traits are later in outcrossers than in selfers of Collinsia. The latter trait was expected to be earlier in P than in M because of sexual selection for early seed siring of pollen.Pivotal ResultsArtificial polyandry for four generations resulted in later flowering start and later anther-stigma contact in P compared to M, and the latter trait was intermediate in S. Thus, P appeared more ‘outcrossing’ than M. Stigma receptivity did not differ between lines. First seed set was earlier in P than in M, as expected from sexual selection.ConclusionsOur results from C. heterophylla experimental evolution lines suggest that a component of sexual selection during outcross pollination could enhance the patterns of floral divergence commonly found between outcrossers and selfers.

scholarly journals Experimental evolution reveals trade-offs between mating and immunity

2013 ◽  
Vol 9 (4) ◽  
pp. 20130262 ◽  
Author(s):  
Kathryn B. McNamara ◽  
Nina Wedell ◽  
Leigh W. Simmons
Keyword(s):  
Sexual Selection ◽  
Experimental Evolution ◽  
Reproductive Traits ◽  
Plodia Interpunctella ◽  
Lytic Activity ◽  
Male Mating ◽  
Trade Offs ◽  
Indian Meal ◽  
System Maintenance ◽  
Significant Divergence

Immune system maintenance and upregulation is costly. Sexual selection intensity, which increases male investment into reproductive traits, is expected to create trade-offs with immune function. We assayed phenoloxidase (PO) and lytic activity of individuals from populations of the Indian meal moth, Plodia interpunctella , which had been evolving under different intensities of sexual selection. We found significant divergence among populations, with males from female-biased populations having lower PO activity than males from balanced sex ratio or male-biased populations. There was no divergence in anti-bacterial lytic activity. Our data suggest that it is the increased male mating demands in female-biased populations that trades-off against immunity, and not the increased investment in sperm transfer per mating that characterizes male-biased populations.

scholarly journals The sexual selection paradigm: have we overlooked other mechanisms in the evolution of male ornaments?

2015 ◽  
Vol 282 (1816) ◽  
pp. 20151987 ◽  
Author(s):  
Ulrika Candolin ◽  
Iina Tukiainen
Keyword(s):  
Sexual Selection ◽  
Mating Success ◽  
Male Reproductive Success ◽  
Social Selection ◽  
Offspring Survival ◽  
Social Competition ◽  
Female Ornaments ◽  
Mating Opportunities ◽  
Selection For ◽  
Male Ornaments

Extravagant male ornaments expressed during reproduction are almost invariably assumed to be sexually selected and evolve through competition for mating opportunities. Yet in species where male reproductive success depends on the defence of offspring, male ornaments could also evolve through social competition for offspring survival. However, in contrast to female ornaments, this possibility has received little attention in males. We show that a male ornament that is traditionally assumed to be sexually selected—the red nuptial coloration of the three-spined stickleback—is under stronger selection for offspring survival than for mating success. Males express most coloration during parenting, when they no longer attract females, and the colour correlates with nest retention and hatching success but not with attractiveness to females. This contradicts earlier assumptions and suggests that social selection for offspring survival rather than for sexual selection for mating success is the main mechanism maintaining the ornament in the population. These results suggest that we should consider other forms of social selection beyond sexual selection when seeking to explain the function and evolution of male ornaments. An incorrect assignment of selection pressures could hamper our understanding of evolution.

scholarly journals Trait-specific trade-offs prevent niche expansion in two parasites

2019 ◽  
Author(s):  
Eva J. P. Lievens ◽  
Yannis Michalakis ◽  
Thomas Lenormand
Keyword(s):  
Experimental Work ◽  
Host Species ◽  
Experimental Evolution ◽  
Brine Shrimp ◽  
Spore Production ◽  
The Other ◽  
Host Specialization ◽  
Trade Off ◽  
Trade Offs ◽  
Evolution Approach

AbstractThe evolution of host specialization has been studied intensively, yet it is still often difficult to determine why parasites do not evolve broader niches – in particular when the available hosts are closely related and ecologically similar. Here, we used an experimental evolution approach to study the evolution of host specialization, and its underlying traits, in two sympatric parasites: Anostracospora rigaudi and Enterocytospora artemiae, microsporidians infecting the brine shrimp Artemia franciscana and Artemia parthenogenetica. In the field, both parasites regularly infect both hosts, yet experimental work has revealed that they are each partially specialized. We serially passaged the parasites on one, the other, or an alternation of the two hosts; after ten passages, we assayed the infectivity, virulence, and spore production rate of the evolved lines. In accordance with previous studies, A. rigaudi maintained a higher fitness on A. parthenogenetica, and E. artemiae on A. franciscana, in all treatments. The origin of this specialization was not infectivity, which readily evolved and traded off weakly between the host species for both parasites. Instead, the overall specialization was caused by spore production, which did not evolve in any treatment. This suggests the existence of a strong trade-off between spore production in A. franciscana and spore production in A. parthenogenetica, making this trait a barrier to the evolution of generalism in this system. This study highlights that the shape of between-host trade-offs can be very heterogeneous across parasite traits, so that only some traits are pivotal to specialization.

scholarly journals Sexual conflict drives micro- and macroevolution of sexual dimorphism in immunity

2020 ◽  
Author(s):  
Basabi Bagchi ◽  
Quentin Corbel ◽  
Imroze Khan ◽  
Ellen Payne ◽  
Devshuvam Banerji ◽  
...  
Keyword(s):  
Sex Differences ◽  
Sexual Selection ◽  
Sexual Dimorphism ◽  
Mating System ◽  
Sexual Conflict ◽  
Experimental Evolution ◽  
Parasitic Infections ◽  
Expression Of Genes ◽  
Trade Offs ◽  
Seed Beetles

AbstractSexual dimorphism in immunity is believed to reflect sex-differences in trade-offs between competing life history demands. Sexual selection can have major effects on mating rates and sex-specific costs of mating and may thereby influence sex-differences in immunity as well as associated host-pathogen dynamics. Yet, experimental data linking the mating system to evolved sexual dimorphism in immunity are scarce and the direct effects of mating rate on immunity are not well established. Here, we use transcriptomic analyses, experimental evolution and phylogenetic comparative methods to study the association between the mating system and sexual dimorphism in immunity in seed beetles, where mating causes internal injuries in females. We demonstrate that female phenoloxidase (PO) activity, involved in wound healing and defence against parasitic infections, is elevated relative to males as a result of sex-biased expression of genes in the proPO activating cascade. We document substantial phenotypic plasticity in female PO activity in response to mating and show that experimental evolution under enforced monogamy (relative to natural polygamy) rapidly decreases female (but not male) PO activity. The evolution of decreased PO in monogamous females was accompanied by increased tolerance to bacterial infection unrelated to mating. This implies that female responses to costly mating may trade off with other aspects of immune defence. Finally, female (but not male) PO activity show correlated evolution with the perceived harmfulness of male genitalia across 12 species of seed beetles, suggesting that sexual conflict has a significant influence on sexual dimorphisms in immunity in this group of insects. Our results thus provide a proximate and ultimate understanding of the links between sexual selection and sexual dimorphism in immunity.

scholarly journals Carabid Beetle (Coleoptera: Carabidae) Response to Soil Properties of Urban Wastelands in Warsaw, Poland

2020 ◽  
Vol 12 (24) ◽  
pp. 10673
Author(s):  
Axel Schwerk ◽  
Marzena Wińska-Krysiak ◽  
Arkadiusz Przybysz ◽  
Ewa Zaraś-Januszkiewicz ◽  
Piotr Sikorski
Keyword(s):  
Negative Impact ◽  
Carabid Beetle ◽  
Carabid Beetles ◽  
Soil Parameters ◽  
City Development ◽  
Space Management ◽  
Trade Offs ◽  
Beetle Assemblages ◽  
Trace Element Contamination ◽  
The One

Urban wasteland is of special interest to city planners. However, to integrate such areas into city space management with consideration of nature conservation aspects, a sound assessment of their ecological potential is necessary. The aim of this paper was to analyze whether carabid beetle assemblages of the wastelands are affected by soil parameters, particularly trace element contamination. Therefore, we studied the carabid fauna in relation to selected soil parameters on 56 sampling plots situated in 24 wastelands located in the city of Warsaw (Poland). The results have confirmed our assumptions that the number of species, as well as the number of individual carabid beetles, are negatively affected by an increasing amount of pollutants in the soil. Particularly, the trace elements Pb, Cu, and Cd showed a significantly negative impact. The results are of value when it comes to the use of urban wastelands in the context of sustainable city development. Future use of urban wastelands will be faced with trade-offs between the use for public interests (e.g., housing space) and ecological interests. Phytoremediation and entomoremediation may be included in decontamination measures. The results of studies, such as the one conducted by us, may help to select the respective wastelands for certain purposes.

scholarly journals Natural selection increases female fitness by reversing the exaggeration of a male sexually selected trait

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kensuke Okada ◽  
Masako Katsuki ◽  
Manmohan D. Sharma ◽  
Katsuya Kiyose ◽  
Tomokazu Seko ◽  
...  
Keyword(s):  
Sexual Selection ◽  
Natural Selection ◽  
Experimental Evolution ◽  
Genetic Correlations ◽  
Lifetime Reproductive Success ◽  
Fundamental Theory ◽  
Female Fitness ◽  
Male Trait ◽  
Flour Beetles ◽  
Male Specific

AbstractTheory shows how sexual selection can exaggerate male traits beyond naturally selected optima and also how natural selection can ultimately halt trait elaboration. Empirical evidence supports this theory, but to our knowledge, there have been no experimental evolution studies directly testing this logic, and little examination of possible associated effects on female fitness. Here we use experimental evolution of replicate populations of broad-horned flour beetles to test for effects of sex-specific predation on an exaggerated sexually selected male trait (the mandibles), while also testing for effects on female lifetime reproductive success. We find that populations subjected to male-specific predation evolve smaller sexually selected mandibles and this indirectly increases female fitness, seemingly through intersexual genetic correlations we document. Predation solely on females has no effects. Our findings support fundamental theory, but also reveal unforseen outcomes—the indirect effect on females—when natural selection targets sex-limited sexually selected characters.

scholarly journals Sexual conflict drives micro- and macroevolution of sexual dimorphism in immunity

BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Basabi Bagchi ◽  
Quentin Corbel ◽  
Imroze Khan ◽  
Ellen Payne ◽  
Devshuvam Banerji ◽  
...  
Keyword(s):  
Sex Differences ◽  
Sexual Dimorphism ◽  
Mating System ◽  
Sexual Conflict ◽  
Experimental Evolution ◽  
Parasitic Infections ◽  
Pathogen Dynamics ◽  
Trade Offs ◽  
Host Pathogen ◽  
Seed Beetles

Abstract Background Sexual dimorphism in immunity is believed to reflect sex differences in reproductive strategies and trade-offs between competing life history demands. Sexual selection can have major effects on mating rates and sex-specific costs of mating and may thereby influence sex differences in immunity as well as associated host–pathogen dynamics. Yet, experimental evidence linking the mating system to evolved sexual dimorphism in immunity are scarce and the direct effects of mating rate on immunity are not well established. Here, we use transcriptomic analyses, experimental evolution and phylogenetic comparative methods to study the association between the mating system and sexual dimorphism in immunity in seed beetles, where mating causes internal injuries in females. Results We demonstrate that female phenoloxidase (PO) activity, involved in wound healing and defence against parasitic infections, is elevated relative to males. This difference is accompanied by concomitant sex differences in the expression of genes in the prophenoloxidase activating cascade. We document substantial phenotypic plasticity in female PO activity in response to mating and show that experimental evolution under enforced monogamy (resulting in low remating rates and reduced sexual conflict relative to natural polygamy) rapidly decreases female (but not male) PO activity. Moreover, monogamous females had evolved increased tolerance to bacterial infection unrelated to mating, implying that female responses to costly mating may trade off with other aspects of immune defence, an hypothesis which broadly accords with the documented sex differences in gene expression. Finally, female (but not male) PO activity shows correlated evolution with the perceived harmfulness of male genitalia across 12 species of seed beetles, suggesting that sexual conflict has a significant influence on sexual dimorphisms in immunity in this group of insects. Conclusions Our study provides insights into the links between sexual conflict and sexual dimorphism in immunity and suggests that selection pressures moulded by mating interactions can lead to a sex-specific mosaic of immune responses with important implications for host–pathogen dynamics in sexually reproducing organisms.

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