Maternally-transferred thyroid hormones and life-history variation in birds

AbstractLife-history traits vary largely across species and several physiological parameters have been proposed to be associated with life-history variation, such as metabolic rates, glucocorticoids, and oxidative stress. Interestingly, the association between thyroid hormones (THs) and life history variation has never been considered, despite a close interaction between THs and these physiological traits. Because of the crucial effects on embryonic development, THs can also induce transgenerational plasticity when transferred to developing offspring, for instance, via egg yolks in birds. In this study, we compiled a unique data set of maternal yolk THs in 34 bird species across 17 families and 6 orders, and tested for associations with various life-history traits. Our phylogenetic mixed models indicated that both concentrations and total amounts of the two most important forms of THs (T3 and T4) were higher in the eggs of migratory species than in those of resident species, and that there were higher total amounts of T3 in the eggs of precocial species than in those of altricial species. However, maternal THs did not show clear associations with any traits of the pace-of-life syndrome, such as developmental duration, growth rate, or lifespan. When taking environmental factors into account, we found that captive species deposited higher TH concentrations and larger amounts in the egg yolks than wild species. These findings suggest that maternal THs are likely involved in the evolution of life-history variation, or vice versa.

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The Phylogenetic Approach to Avian Life Histories: An Important Complement to Within-Population Studies

The Condor ◽

10.1093/condor/102.1.52 ◽

2000 ◽

Vol 102 (1) ◽

pp. 52-59 ◽

Cited By ~ 1

Author(s):

David W. Winkler

Keyword(s):

Life History ◽

Life Histories ◽

Life History Traits ◽

Statistical Convergence ◽

Phylogenetic Analyses ◽

Life History Evolution ◽

Life History Variation ◽

Evolution Of Life ◽

Character Variation

Abstract In recent years, two approaches have emerged for the analysis of character evolution: the largely statistical “convergence” approach and the mainly cladistic “homology” approach. I discuss the strengths and weaknesses of these approaches as they apply to phylogenetic analyses of life-history variation in birds. Using examples from analyses of character variation in swallows, I suggest that the phylogenetic approach yields distinctive insights into the selective role of the environment and other characters of the organism on the evolution of life-history traits. This view thus has the potential of bringing together micro- and macro-evolutionary views of life-history evolution.

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Early-life telomere length covaries with life-history traits and scales with chromosome length in birds

10.1101/2021.08.07.455497 ◽

2021 ◽

Author(s):

Michael Le Pepke ◽

Thor Harald Ringsby ◽

Dan T. A. Eisenberg

Keyword(s):

Life History ◽

Telomere Length ◽

Dna Sequences ◽

Early Life ◽

Life History Traits ◽

Bird Species ◽

Chromosome Length ◽

Life History Variation ◽

Trade Offs ◽

Phylogenetic Framework

Telomeres, the short DNA sequences that protect chromosome ends, are an ancient molecular structure, which is highly conserved across most eukaryotes. Species differ in their telomere lengths, but the causes of this variation are not well understood. Here, we demonstrate that mean early-life telomere length is an evolutionary labile trait across 58 bird species (representing 35 families in 12 orders) with the greatest trait diversity found among passerines. Among these species, telomere length is significantly negatively associated with the fast-slow axis of life-history variation, suggesting that telomere length may have evolved to mediate trade-offs between physiological requirements underlying the diversity of pace-of-life strategies in birds. Curiously, within some species, larger individual chromosome size predicts longer telomere lengths on that chromosome, leading to the suggestion that telomere length also covaries with chromosome length across species. We show that longer mean chromosome length or genome size tends to be associated with longer mean early-life telomere length (measured across all chromosomes) within a phylogenetic framework constituting up to 32 bird species. Combined, our analyses generalize patterns previously found within a few species and provide potential adaptive explanations for the 10-fold variation in telomere lengths observed among birds.

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Demographic life history traits of reproductive natterjack toads (Bufo calamita) vary between northern and southern latitudes

Amphibia-Reptilia ◽

10.1163/156853806778189918 ◽

2006 ◽

Vol 27 (3) ◽

pp. 365-375 ◽

Cited By ~ 31

Author(s):

Delfi Sanuy ◽

Christoph Leskovar ◽

Neus Oromi ◽

Ulrich Sinsch

Keyword(s):

Life History ◽

Life History Traits ◽

Large Female ◽

Breeding Period ◽

Female Size ◽

Data Set ◽

Bufo Calamita ◽

Trade Offs ◽

Age Variation ◽

The Cost

AbstractDemographic life history traits were investigated in three Bufo calamita populations in Germany (Rhineland-Palatinate: Urmitz, 50°N; 1998-2000) and Spain (Catalonia: Balaguer, Mas de Melons, 41°N; 2004). We used skeletochronology to estimate the age as number of lines of arrested growth in breeding adults collected during the spring breeding period (all localities) and during the summer breeding period (only Urmitz). A data set including the variables sex, age and size of 185 males and of 87 females was analyzed with respect to seven life history traits (age and size at maturity of the youngest first breeders, age variation in first breeders, longevity, potential reproductive lifespan, median lifespan, age-size relationship). Spring and summer cohorts at the German locality differed with respect to longevity and potential reproductive lifespan by one year in favour of the early breeders. The potential consequences on fitness and stability of cohorts are discussed. Latitudinal variation of life history traits was mainly limited to female natterjacks in which along a south-north gradient longevity and potential reproductive lifespan increased while size decreased. These results and a review of published information on natterjack demography suggest that lifetime number of offspring seem to be optimized by locally different trade-offs: large female size at the cost of longevity in southern populations and increased longevity at the cost of size in northern ones.

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A Primer of Life Histories

10.1093/oso/9780198839873.001.0001 ◽

2021 ◽

Author(s):

Jeffrey A. Hutchings

Keyword(s):

Life History ◽

Life Histories ◽

Life History Theory ◽

Life History Traits ◽

Reproductive Effort ◽

Effective Means ◽

Academic Experience ◽

Sustainable Exploitation ◽

Evolution Of Life ◽

Opportune Time

Life histories describe how genotypes schedule their reproductive effort throughout life in response to factors that affect their survival and fecundity. Life histories are solutions that selection has produced to solve the problem of how to persist in a given environment. These solutions differ tremendously within and among species. Some organisms mature within months of attaining life, others within decades; some produce few, large offspring as opposed to numerous, small offspring; some reproduce many times throughout their lives while others die after reproducing just once. The exponential pace of life-history research provides an opportune time to engage and re-engage new generations of students and researchers on the fundamentals and applications of life-history theory. Chapters 1 through 4 describe the fundamentals of life-history theory. Chapters 5 through 8 focus on the evolution of life-history traits. Chapters 9 and 10 summarize how life-history theory and prediction has been applied within the contexts of conservation and sustainable exploitation. This primer offers an effective means of rendering the topic accessible to readers from a broad range of academic experience and research expertise.

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The Evolution of Life History Traits: A Critique of the Theory and a Review of the Data

Annual Review of Ecology and Systematics ◽

10.1146/annurev.es.08.110177.001045 ◽

1977 ◽

Vol 8 (1) ◽

pp. 145-171 ◽

Cited By ~ 683

Author(s):

S C Stearns

Keyword(s):

Life History ◽

Life History Traits ◽

Evolution Of Life

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Life-history variation of drosophila subobscura under lead pollution depends on population history

Genetika ◽

10.2298/gensr1403693k ◽

2014 ◽

Vol 46 (3) ◽

pp. 693-703 ◽

Cited By ~ 1

Author(s):

Bojan Kenig ◽

Aleksandra Patenkovic ◽

Marko Andjelkovic ◽

Marina Stamenkovic-Rada

Keyword(s):

Heavy Metal ◽

Life History ◽

Metal Contamination ◽

Life History Traits ◽

Heavy Metal Contamination ◽

Developmental Time ◽

Drosophila Subobscura ◽

Life History Variation ◽

Laboratory Conditions ◽

Coefficients Of Variation

Contamination represents environmental stress that can affect genetic variability of populations, thus influencing the evolutionary processes. In this study, we evaluate the relationship between heavy metal contamination (Pb) and phenotypic variation, assessed by coefficients of variation (CV) of life-history traits. To investigate the consequences of population origin on variation of life history traits in Drosophila subobscura in response to different laboratory conditions we compared populations from relatively polluted and unpolluted environments. Prior to experiment, flies from natural populations were reared for two generations in standard Drosophila laboratory conditions. Afterwards, all flies were cultured on three different media: one medium without lead as the control, and the other two with different concentrations of lead. Coefficients of variation (CV) of life- history traits (fecundity, egg-to-adult viability and developmental time) were analyzed on flies sampled in generations F2, F5 and F8 from these three groups. In later generations samples from both polluted and unpolluted environments showed the increased fecundity variation on media with lead. This increase is expressed more in population from unpolluted environment. On contrary, population from unpolluted environment had increased variation of developmental time in earlier, F2 generation, compared to the population from polluted environment. Our results showed that the response to heavy metal contamination depends on the evolutionary history of the populations regarding habitat pollution.

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Loci, genes, and gene networks associated with life history variation in a model ecological organism,Daphnia pulex(complex)

10.1101/436733 ◽

2018 ◽

Author(s):

Jacob W. Malcom ◽

Thomas E. Juenger ◽

Mathew A. Leibold

Keyword(s):

Gene Expression ◽

Genetic Variation ◽

Life History ◽

Molecular Basis ◽

Life History Traits ◽

Evolutionary Dynamics ◽

Daphnia Pulex ◽

Life History Trait ◽

Life History Variation ◽

Trait Variation

ABSTRACTBackgroundIdentifying the molecular basis of heritable variation provides insight into the underlying mechanisms generating phenotypic variation and the evolutionary history of organismal traits. Life history trait variation is of central importance to ecological and evolutionary dynamics, and contemporary genomic tools permit studies of the basis of this variation in non-genetic model organisms. We used high density genotyping, RNA-Seq gene expression assays, and detailed phenotyping of fourteen ecologically important life history traits in a wild-caught panel of 32Daphnia pulexclones to explore the molecular basis of trait variation in a model ecological species.ResultsWe found extensive phenotypic and a range of heritable genetic variation (~0 < H2< 0.44) in the panel, and accordingly identify 75-261 genes—organized in 3-6 coexpression modules—associated with genetic variation in each trait. The trait-related coexpression modules possess well-supported promoter motifs, and in conjunction with marker variation at trans- loci, suggest a relatively small number of important expression regulators. We further identify a candidate genetic network with SNPs in eight known transcriptional regulators, and dozens of differentially expressed genes, associated with life history variation. The gene-trait associations include numerous un-annotated genes, but also support several a priori hypotheses, including an ecdysone-induced protein and several Gene Ontology pathways.ConclusionThe genetic and gene expression architecture ofDaphnialife history traits is complex, and our results provide numerous candidate loci, genes, and coexpression modules to be tested as the molecular mechanisms that underlieDaphniaeco-evolutionary dynamics.

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Density Dependence, Evolutionary Optimization, and the Diversification of Avian Life Histories

The Condor ◽

10.1093/condor/102.1.9 ◽

2000 ◽

Vol 102 (1) ◽

pp. 9-22 ◽

Cited By ~ 15

Author(s):

Robert E. Ricklefs

Keyword(s):

Life History ◽

Life Table ◽

Life Histories ◽

Life History Traits ◽

Evolutionary Ecology ◽

Reproductive Rate ◽

Empirical Modeling ◽

Adult Survival ◽

Life History Variation ◽

Evolutionary Response

Abstract Although we have learned much about avian life histories during the 50 years since the seminal publications of David Lack, Alexander Skutch, and Reginald Moreau, we still do not have adequate explanations for some of the basic patterns of variation in life-history traits among birds. In part, this reflects two consequences of the predominance of evolutionary ecology thinking during the past three decades. First, by blurring the distinction between life-history traits and life-table variables, we have tended to divorce life histories from their environmental context, which forms the link between the life history and the life table. Second, by emphasizing constrained evolutionary responses to selective factors, we have set aside alternative explanations for observed correlations among life-history traits and life-table variables. Density-dependent feedback and independent evolutionary response to correlated aspects of the environment also may link traits through different mechanisms. Additionally, in some cases we have failed to evaluate quantitatively ideas that are compelling qualitatively, ignored or explained away relevant empirical data, and neglected logical implications of certain compelling ideas. Comparative analysis of avian life histories shows that species are distributed along a dominant slow-fast axis. Furthermore, among birds, annual reproductive rate and adult mortality are directly proportional to each other, requiring that pre-reproductive survival is approximately constant. This further implies that age at maturity increases dramatically with increasing adult survival rate. The significance of these correlations is obscure, particularly because survival and reproductive rates at each age include the effects of many life-history traits. For example, reproductive rate is determined by clutch size, nesting success, season length, and nest-cycle length, each of which represents the outcome of many different interactions of an individual's life-history traits with its environment. Resolution of the most basic issues raised by patterns of life histories clearly will require innovative empirical, modeling, and experimental approaches. However, the most fundamental change required at this time is a broadening of the evolutionary ecology paradigm to include a variety of alternative mechanisms for generating patterns of life-history variation.

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