Artificial selection on sexual aggression: Correlated traits and possible trade‐offs

Pigmentation is a classic phenotype that varies widely and adaptively in nature both within and among taxa. Genes underlying pigmentation phenotype are highly pleiotropic, creating the potential for functional trade-offs. However, the basic tenets of this trade-off hypothesis with respect to life-history traits have not been directly addressed. In natural populations of Drosophila melanogaster , the degree of melanin pigmentation covaries with fecundity and several other fitness traits. To examine correlations and potential trade-offs associated with variation in pigmentation, we selected replicate outbred populations for extreme pigmentation phenotypes. Replicate populations responded rapidly to the selection regime and after 100 generations of artificial selection were phenotyped for pigmentation as well as the two basic fitness parameters of fecundity and longevity. Our data demonstrate that selection on pigmentation resulted in a significant shift in both fecundity and longevity profiles. Selection for dark pigmentation resulted in greater fecundity and no pronounced change in longevity, whereas selection for light pigmentation decreased longevity but did not affect fecundity. Our results indicate the pleiotropic nature of alleles underlying pigmentation phenotype and elucidate possible trade-offs between pigmentation and fitness traits that may shape patterns of phenotypic variation in natural populations.

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Syndromes in suites of correlated traits suggest multiple mechanisms facilitating invasion in a plant range-expander

NeoBiota ◽

10.3897/neobiota.37.21470 ◽

2018 ◽

Vol 37 ◽

pp. 1-22 ◽

Cited By ~ 2

Author(s):

Lisa Johanna Tewes ◽

Caroline Mueller

Keyword(s):

Common Garden ◽

Plant Invasions ◽

Individual Species ◽

Multiple Traits ◽

Correlated Traits ◽

Invasion Mechanisms ◽

Trade Offs ◽

Population Origin ◽

Species Specific ◽

Native Invasive

Various mechanisms can facilitate the success of plant invasions simultaneously, but may be difficult to disentangle. In the present study, plants of the range-expanding species Bunias orientalis from native, invasive and naturalised, not yet invasive populations were compared in a field common garden over two years. Plants were grown under two nitrate-regimes and multiple traits regarding growth, defence, antagonist loads and reproduction were measured. A rank-based clustering approach was used to assign correlated traits to distinct suites. These suites were analysed for “syndromes” that are expressed as a function of population origin and/or fertilisation treatment and might represent different invasion mechanisms. Indeed, distinct suites of traits were differentially affected by these factors. The results suggest that several pre-adaptation properties, such as certain growth characteristics and intraspecific chemical variation, as well as post-introduction adaptations to antagonists and resource availability in novel habitats, are candidate mechanisms that facilitate the success of invasive B. orientalis in parallel. It was concluded that rank-based clustering is a robust and expedient approach to integrate multiple traits for elucidating invasion syndromes within individual species. Studying a multitude of traits at different life-history and establishment stages of plants grown under distinct resource treatments reveals species-specific trade-offs and resource sinks and simplifies the interpretation of trait functions for the potential invasive success of plants.

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Artificial selection shifts flowering phenology and other correlated traits in an autotetraploid herb

Heredity ◽

10.1038/sj.hdy.6801043 ◽

2007 ◽

Vol 99 (6) ◽

pp. 641-648 ◽

Cited By ~ 48

Author(s):

K S Burgess ◽

J R Etterson ◽

L F Galloway

Keyword(s):

Artificial Selection ◽

Flowering Phenology ◽

Correlated Traits

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Age and Size at Maturity

Evolutionary Ecology ◽

10.1093/oso/9780195131543.003.0013 ◽

2001 ◽

Author(s):

Derek A. Roff

Keyword(s):

Artificial Selection ◽

Additive Genetic Variance ◽

Natural Populations ◽

The Arctic ◽

Size At Maturity ◽

Age At Maturity ◽

Large Size ◽

Quantitative Genetic ◽

Trade Offs ◽

The Many

Age and size at maturity have been an object of interest to humans since the domestication of animals and plants, for one of the objectives of domestication was to produce an organism that grew fast and matured early at a large size. Selection was also practiced to produce animals that could be used for such purposes as hunting and portaging, and to produce products for pleasure alone, as seen in the many ornamental varieties of dogs, cats, goldfish, pigeons, and plants. All of these instances demonstrate that age and size at maturity are traits that are relatively easily molded by artificial selection and, by extension, natural selection. Historically, artificial selection experiments were concerned not with the evolution of age and size at maturity in natural populations but with the production of economically more valuable plants and animals. Recently, there has been a substantial increase in the quantitative genetic analysis of nondomesticated organisms, which has shown that, with respect to morphological traits such as adult size, there is typically abundant additive genetic variance, with heritabilities averaging approximately 0.4 (reviewed in Roff 1997). Life history traits, such as the age at maturity, show, on average, lower heritabilities (approx. 0.26) but still enough for rapid evolutionary change. Quantitative genetic analyses have shown that age and size at maturity can evolve, but the most significant advances in our understanding of the factors favoring particular age at maturity/body size combinations are due to mathematical models predicated upon the assumption that selection maximizes some fitness measure such as the rate of increase, r. In a paper entitled “Adaptive Significance of Large Size and Long Life of the Chaetognath Sagitta elegans in the Arctic,” McLaren (1966) produced a seminal analysis in which he incorporated all the important elements that have appeared in subsequent analyses of the evolution of age and size at maturity. Specifically, McLaren attempted to take into account the trade-offs produced by increased fecundity being bought at the expense of delayed maturity and increased mortality. In this chapter, I shall primarily consider analyses that have followed in McLaren’s footsteps.

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Novel players fine-tune plant trade-offs

Essays in Biochemistry ◽

10.1042/bse0580083 ◽

2015 ◽

Vol 58 ◽

pp. 83-100 ◽

Cited By ~ 25

Author(s):

Selena Gimenez-Ibanez ◽

Marta Boter ◽

Roberto Solano

Keyword(s):

Ubiquitin Ligase ◽

Feedback Loop ◽

Molecular Level ◽

26S Proteasome ◽

Signalling Molecules ◽

Transcriptional Reprogramming ◽

Trade Offs ◽

Jaz Proteins ◽

Regulatory Feedback Loop ◽

Fine Tune

Jasmonates (JAs) are essential signalling molecules that co-ordinate the plant response to biotic and abiotic challenges, as well as co-ordinating several developmental processes. Huge progress has been made over the last decade in understanding the components and mechanisms that govern JA perception and signalling. The bioactive form of the hormone, (+)-7-iso-jasmonyl-l-isoleucine (JA-Ile), is perceived by the COI1–JAZ co-receptor complex. JASMONATE ZIM DOMAIN (JAZ) proteins also act as direct repressors of transcriptional activators such as MYC2. In the emerging picture of JA-Ile perception and signalling, COI1 operates as an E3 ubiquitin ligase that upon binding of JA-Ile targets JAZ repressors for degradation by the 26S proteasome, thereby derepressing transcription factors such as MYC2, which in turn activate JA-Ile-dependent transcriptional reprogramming. It is noteworthy that MYCs and different spliced variants of the JAZ proteins are involved in a negative regulatory feedback loop, which suggests a model that rapidly turns the transcriptional JA-Ile responses on and off and thereby avoids a detrimental overactivation of the pathway. This chapter highlights the most recent advances in our understanding of JA-Ile signalling, focusing on the latest repertoire of new targets of JAZ proteins to control different sets of JA-Ile-mediated responses, novel mechanisms of negative regulation of JA-Ile signalling, and hormonal cross-talk at the molecular level that ultimately determines plant adaptability and survival.

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Dual Goals for Speed and Accuracy on the Same Performance Task

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000063 ◽

2012 ◽

Vol 11 (3) ◽

pp. 118-126 ◽

Cited By ~ 3

Author(s):

Olive Emil Wetter ◽

Jürgen Wegge ◽

Klaus Jonas ◽

Klaus-Helmut Schmidt

Keyword(s):

Memory Scanning ◽

Performance Task ◽

Performance Tasks ◽

Trade Off ◽

Test Experiment ◽

Trade Offs ◽

New Finding ◽

Sternberg Paradigm ◽

Speed Accuracy ◽

Speed And Accuracy

In most work contexts, several performance goals coexist, and conflicts between them and trade-offs can occur. Our paper is the first to contrast a dual goal for speed and accuracy with a single goal for speed on the same task. The Sternberg paradigm (Experiment 1, n = 57) and the d2 test (Experiment 2, n = 19) were used as performance tasks. Speed measures and errors revealed in both experiments that dual as well as single goals increase performance by enhancing memory scanning. However, the single speed goal triggered a speed-accuracy trade-off, favoring speed over accuracy, whereas this was not the case with the dual goal. In difficult trials, dual goals slowed down scanning processes again so that errors could be prevented. This new finding is particularly relevant for security domains, where both aspects have to be managed simultaneously.

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