scholarly journals On the ecology and distribution of steelhead (Oncorhynchus mykiss) in California’s Eel River

2020 ◽  
Author(s):  
Samantha H. Kannry ◽  
Sean M. O’Rourke ◽  
Suzanne J Kelson ◽  
Michael R Miller
Keyword(s):  
Life History ◽  
Oncorhynchus Mykiss ◽  
Pacific Salmon ◽  
Management Strategies ◽  
Life History Strategies ◽  
Past Century ◽  
Life History Variation ◽  
Eel River ◽  
Phenotypic Complexity ◽  
Run Timing

AbstractPreservation of life-history and other phenotypic complexity is central to the resilience of Pacific salmon stocks. Steelhead (Oncorhynchus mykiss) express a diversity of life history strategies such as the propensity to migrate (anadromy/residency) and the timing and state of maturation upon return to freshwater (run-timing), providing an opportunity to study adaptive phenotypic complexity. Historically, the Eel River supported upwards of one million salmon and steelhead, but the past century has seen dramatic declines of all salmonids in the watershed. Here we investigate life history variation in Eel River steelhead by using Rapture sequencing, on thousands of individuals, to genotype the region diagnostic for run-timing (GREB1L) and the region strongly associated with residency/anadromy (OMY5) in the Eel River and other locations, as well as determine patterns of overall genetic differentiation. Our results provide insight into many conservation related issues. For example, we found distinct segregation between winter and summer-run steelhead correlated with flow dependent barriers in major forks of the Eel; that summer-run steelhead inhabited the upper Eel prior to construction of an impassable dam, and that both life-history and overall genetic diversity have been maintained in the resident trout population above; and no evidence of the summer-run allele in the South Fork Eel, indicating that summer run-timing cannot be expected to arise from standing genetic variation in this and other populations that lack the summer-run phenotype. The results presented in this study provide valuable information for designing future restoration and management strategies for O. mykiss in Northern California and beyond.

scholarly journals On the Ecology and Distribution of Steelhead (Oncorhynchus mykiss) in California’s Eel River

2020 ◽  
Vol 111 (6) ◽  
pp. 548-563
Author(s):  
Samantha H Kannry ◽  
Sean M O’Rourke ◽  
Suzanne J Kelson ◽  
Michael R Miller
Keyword(s):  
Life History ◽  
Oncorhynchus Mykiss ◽  
Pacific Salmon ◽  
Management Strategies ◽  
Life History Strategies ◽  
Past Century ◽  
Life History Variation ◽  
Eel River ◽  
Phenotypic Complexity ◽  
Run Timing

Abstract The preservation of life history and other phenotypic complexity is central to the resilience of Pacific salmon stocks. Steelhead (Oncorhynchus mykiss) express a diversity of life-history strategies such as the propensity to migrate (anadromy/residency) and the timing and state of maturation upon return to freshwater (run-timing), providing an opportunity to study adaptive phenotypic complexity. Historically, the Eel River supported upwards of 1 million salmon and steelhead, but the past century has seen dramatic declines of all salmonids in the watershed. Here we investigate life-history variation in Eel River steelhead by using Rapture sequencing, on thousands of individuals, to genotype the region diagnostic for run-timing (GREB1L) and the region strongly associated with residency/anadromy (OMY5) in the Eel River and other locations, as well as determine patterns of overall genetic differentiation. Our results provide insight into many conservation-related issues. For example, we found that distinct segregation between winter and summer-run steelhead correlated with flow-dependent barriers in major forks of the Eel, that summer-run steelhead inhabited the upper Eel prior to construction of an impassable dam, and that both life history and overall genetic diversity have been maintained in the resident trout population above; and we found no evidence of the summer-run allele in the South Fork Eel, indicating that summer run-timing cannot be expected to arise from standing genetic variation in this and other populations that lack the summer-run phenotype. The results presented in this study provide valuable information for designing future restoration and management strategies for O. mykiss in Northern California and beyond.

Life History Strategies

2018 ◽  
pp. 95-126
Author(s):  
Marco Del Giudice
Keyword(s):  
Life History ◽  
Individual Differences ◽  
Life History Theory ◽  
Human Life ◽  
Life History Strategy ◽  
Current Theory ◽  
Life History Strategies ◽  
Extended Model ◽  
Life History Variation ◽  
Basic Model

The chapter introduces the basics of life history theory, the concept of life history strategy, and the fast–slow continuum of variation. After reviewing applications to animal behavior and physiology, the chapter reviews current theory and evidence on individual differences in humans as manifestations of alternative life history strategies. The chapter first presents a “basic model” of human life history–related traits, then advances an “extended model” that identifies multiple cognitive-behavioral profiles within fast and slow strategies. Specifically, it is proposed that slow strategies comprise prosocial/caregiving and skilled/provisioning profiles, whereas fast strategies comprise antisocial/exploitative and seductive/creative profiles. The chapter also reviews potential neurobiological markers of life history variation and considers key methodological issues in this area.

scholarly journals Evolutionary heritage influences Amazon tree ecology

2016 ◽  
Vol 283 (1844) ◽  
pp. 20161587 ◽  
Author(s):  
Fernanda Coelho de Souza ◽  
Kyle G. Dexter ◽  
Oliver L. Phillips ◽  
Roel J. W. Brienen ◽  
Jerome Chave ◽  
...  
Keyword(s):  
Life History ◽  
Evolutionary History ◽  
Large Scale ◽  
Phylogenetic Signal ◽  
Life History Strategies ◽  
Relative Importance ◽  
Life History Variation ◽  
Trait Variation ◽  
Closed Canopy ◽  
Repeated Evolution

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change.

scholarly journals Rapid parallel evolution of standing variation in a single, complex, genomic region is associated with life history in steelhead/rainbow trout

2014 ◽  
Vol 281 (1783) ◽  
pp. 20140012 ◽  
Author(s):  
Devon E. Pearse ◽  
Michael R. Miller ◽  
Alicia Abadía-Cardoso ◽  
John Carlos Garza
Keyword(s):  
Life History ◽  
Rainbow Trout ◽  
Parallel Evolution ◽  
Genomic Region ◽  
Life History Strategies ◽  
Strong Linkage Disequilibrium ◽  
Rapid Adaptation ◽  
Life History Variation ◽  
Standing Variation ◽  
Genomic Regions

Rapid adaptation to novel environments may drive changes in genomic regions through natural selection. Such changes may be population-specific or, alternatively, may involve parallel evolution of the same genomic region in multiple populations, if that region contains genes or co-adapted gene complexes affecting the selected trait(s). Both quantitative and population genetic approaches have identified associations between specific genomic regions and the anadromous (steelhead) and resident (rainbow trout) life-history strategies of Oncorhynchus mykiss . Here, we use genotype data from 95 single nucleotide polymorphisms and show that the distribution of variation in a large region of one chromosome, Omy5, is strongly associated with life-history differentiation in multiple above-barrier populations of rainbow trout and their anadromous steelhead ancestors. The associated loci are in strong linkage disequilibrium, suggesting the presence of a chromosomal inversion or other rearrangement limiting recombination. These results provide the first evidence of a common genomic basis for life-history variation in O. mykiss in a geographically diverse set of populations and extend our knowledge of the heritable basis of rapid adaptation of complex traits in novel habitats.

scholarly journals Causes and consequences of life-history variation in North American stocks of Pacific cod

2008 ◽  
Vol 66 (2) ◽  
pp. 349-357 ◽  
Author(s):  
Olav A. Ormseth ◽  
Brenda L. Norcross
Keyword(s):  
Life History ◽  
North American ◽  
Egg Production ◽  
Atlantic Cod ◽  
North Pacific Ocean ◽  
Life History Strategies ◽  
Lifetime Reproductive Success ◽  
Life History Variation ◽  
Pacific Cod ◽  
Trade Offs

Abstract Ormseth, O. A., and Norcross, B. L. 2009. Causes and consequences of life-history variation in North American stocks of Pacific cod. – ICES Journal of Marine Science, 66: 349–357. Life-history strategies of four Pacific cod (Gadus macrocephalus) stocks in the eastern North Pacific Ocean are outlined. Southern stocks grew and matured quicker, but reached smaller maximum size and had shorter lifespans than northern stocks. The trade-offs resulted in similar lifetime reproductive success among all stocks. Growth was highly dependent on latitude, but not on temperature, possibly because of differences in the duration of the growing season. Comparisons with Atlantic cod (Gadus morhua) revealed similar latitude/growth relationships among Atlantic cod stocks grouped by geographic region. In Pacific cod, greater size and longevity in the north appeared to be adaptations to overcome environmental constraints on growth and to maintain fitness. An egg production-per-recruit model suggested that the life-history strategy of northern Pacific cod stocks made them less resilient to fishing activity and age truncation than southern stocks.

scholarly journals Life history variation is maintained by fitness trade-offs and negative frequency-dependent selection

2018 ◽  
Vol 115 (17) ◽  
pp. 4441-4446 ◽  
Author(s):  
Mark R. Christie ◽  
Gordon G. McNickle ◽  
Rod A. French ◽  
Michael S. Blouin
Keyword(s):  
Life History ◽  
Reproductive Success ◽  
Life History Strategies ◽  
Lifetime Reproductive Success ◽  
Life History Variation ◽  
Additional Energy ◽  
Frequency Dependent ◽  
Frequency Dependent Selection ◽  
Trade Offs ◽  
Negative Frequency Dependent Selection

The maintenance of diverse life history strategies within and among species remains a fundamental question in ecology and evolutionary biology. By using a near-complete 16-year pedigree of 12,579 winter-run steelhead (Oncorhynchus mykiss) from the Hood River, Oregon, we examined the continued maintenance of two life history traits: the number of lifetime spawning events (semelparous vs. iteroparous) and age at first spawning (2–5 years). We found that repeat-spawning fish had more than 2.5 times the lifetime reproductive success of single-spawning fish. However, first-time repeat-spawning fish had significantly lower reproductive success than single-spawning fish of the same age, suggesting that repeat-spawning fish forego early reproduction to devote additional energy to continued survival. For single-spawning fish, we also found evidence for a fitness trade-off for age at spawning: older, larger males had higher reproductive success than younger, smaller males. For females, in contrast, we found that 3-year-old fish had the highest mean lifetime reproductive success despite the observation that 4- and 5-year-old fish were both longer and heavier. This phenomenon was explained by negative frequency-dependent selection: as 4- and 5-year-old fish decreased in frequency on the spawning grounds, their lifetime reproductive success became greater than that of the 3-year-old fish. Using a combination of mathematical and individual-based models parameterized with our empirical estimates, we demonstrate that both fitness trade-offs and negative frequency-dependent selection observed in the empirical data can theoretically maintain the diverse life history strategies found in this population.

scholarly journals Genome-wide DNA methylation predicts environmentally-driven life history variation in a marine fish

2021 ◽  
Author(s):  
Hugo Cayuela ◽  
Clément Rougeux ◽  
Martin Laporte ◽  
Claire Mérot ◽  
Eric Normandeau ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Life History ◽  
Water Temperature ◽  
Intraspecific Variation ◽  
Marine Fish ◽  
Molecular Mechanisms ◽  
Hatching Success ◽  
Life History Strategies ◽  
Life History Variation ◽  
Genome Wide

AbstractThe molecular mechanisms underlying intraspecific variation in life history strategies are still poorly understood, despite the importance of this question for understanding of organism’s responses to environmental variability. Theoretical work proposed that epigenetic mechanisms such as DNA methylation might regulate intraspecific variation in life history strategies, however this assumption has rarely been verified empirically in wild populations. We examined associations between genome-wide methylation changes and environmentally-driven life history variation in two lineages of a marine fish that diverged approximatively 2.5 Mya, the capelin (Mallotus villosus), from North America and Europe. In both lineages, capelin harbour two contrasted life history strategies: some are strictly semelparous, experience fast actuarial senescence, but benefit from high hatching success by spawning on demersal sites where water temperature is low and relatively stable. In contrast, others are facultative iteroparous, have slower actuarial senescence, and suffer from lower hatching success by breeding in the intertidal zone where temperature is warmer, thermohaline parameters are less stable, and egg desiccation risk is high. Performing whole genome and epigenome sequencing, we showed that these contrasted life history strategies are more likely governed by epigenetic changes than by differences in DNA sequence. While genetic differentiation between the capelin harbouring different life history strategies was negligible, we detected parallel genome-wide methylation changes across lineages. We identified 1,067 differentially methylated regions (DMRs) comprising 15,818 CpGs, with 22% of them located within 5-kb around genes comprising promotor regions. We found that all DMRs were hypermethylated in demersal-spawning individuals. This striking result suggests that lower water temperature at demersal sites leads to an overall hypermethylation of the genome determined during the epigenetic reprogramming occurring over embryonic development. Our study emphasizes that parallel epigenetics changes in lineages with divergent genetic background could have a functional role in the regulation of intraspecific life history variation.

scholarly journals Life history variation across four decades in a diverse population complex of Atlantic salmon in a large subarctic river

2019 ◽  
Vol 76 (1) ◽  
pp. 42-55 ◽  
Author(s):  
Jaakko Erkinaro ◽  
Yann Czorlich ◽  
Panu Orell ◽  
Jorma Kuusela ◽  
Morten Falkegård ◽  
...  
Keyword(s):  
Life History ◽  
Fresh Water ◽  
Life Histories ◽  
Age Distribution ◽  
Large River ◽  
Life History Strategies ◽  
Sampling Effort ◽  
Life History Variation ◽  
Water Age ◽  
Long Term Trends

We used over 154 000 scale samples collected from salmon fisheries in the large River Teno system over a 40-year period to quantify life history diversity and long-term trends. We identified 120 different life history strategies, including combinations of smolt (2–8) and sea ages (1–5) and previous spawning events. Most strategies were rare; 60% of individuals matured after 1 year at sea following 3–5 years in fresh water. Age at maturity changed with an increase in two-sea-winter salmon and previous spawners and a decline in three-sea-winter fish. Smolt age distribution showed a decreasing proportion of age-3 smolts, while that of age-5 smolts increased. Fishing gear and fishing season times selected for fish differing in life history strategies. Temporal variation in life histories reflected changes in both fisheries and the changing environment. There was an inverse relationship between years spent in fresh water and sea age. Biocomplexity was manifested by the multiple year classes (6–11) present in annual runs, which increased with years, reflecting an increase both in previous spawners and sampling effort. The high number of cohorts spawning simultaneously each year indicates strong generational overlap, which has been suggested to maintain genetic diversity and thereby resilience via the portfolio effect.

scholarly journals Life histories as mosaics: plastic and genetic components differ among traits that underpin life-history strategies

2021 ◽  
Author(s):  
Anja Felmy ◽  
David N. Reznick ◽  
Joseph Travis ◽  
Tomos Potter ◽  
Tim Coulson
Keyword(s):  
Life History ◽  
Life Histories ◽  
Environmental Control ◽  
Relative Strength ◽  
Life History Strategies ◽  
Life History Variation ◽  
Genotype By Environment Interactions ◽  
Genotype By Environment ◽  
Genetic Components ◽  
Genes And Environment

AbstractLife-history variation reflects phenotypic variation across suites of traits. Differences among life-history strategies result from genetic differentiation, phenotypic plasticity, and genotype-by-environment interactions. If the relative strength and direction of these components differed among traits underlying a strategy, life histories might not evolve as a cohesive unit.We tested this hypothesis on the high- and low-predation ecotypes of Trinidadian guppies, defined by distinct life-history strategies. Using common garden experiments, we assessed how strongly 36 traits were determined by ancestral habitat (i.e., ecotype) or food availability, a key environmental difference between ecotypes. Our dataset was large (1178 individuals) and included six putatively independent origins of the derived ecotype.Traits could be confidently assigned to four groups, defined by highly significant effects of only food (13 traits), only habitat (6), both (6), or neither (11), revealing substantial variation among traits in levels of genetic and environmental control. Ecotype-food (i.e., genotype-by-environment) interactions were negligible. The directions of plastic and genetic effects were usually aligned.This suggests that life histories are mosaics with unequal rates of phenotypic and evolutionary change. Broadly speaking of “life-history evolution” masks a complex interplay of genes and environment on the multiple traits that underpin life-history strategies.

scholarly journals Cyclical environments drive variation in life history strategies: a general theory of cyclical phenology

2018 ◽  
Author(s):  
John S. Park
Keyword(s):  
Life History ◽  
Life History Theory ◽  
Natural Populations ◽  
Life History Evolution ◽  
Life Cycles ◽  
Life History Strategies ◽  
Life History Variation ◽  
Trade Offs ◽  
Overwhelming Evidence ◽  
Phenological Shifts

ABSTRACTCycles, such as seasons or tides, characterize many systems in nature. Overwhelming evidence shows that climate change-driven alterations to environmental cycles—such as longer seasons— are associated with phenological shifts around the world, suggesting a deep link between environmental cycles and life cycles. However, general mechanisms of life history evolution in cyclical environments are still not well understood. Here I build a demographic framework and ask how life history strategies optimize fitness when the environment perturbs a structured population cyclically, and how strategies should change as cyclicality changes. I show that cycle periodicity alters optimality predictions of classic life history theory because repeated cycles have rippling selective consequences over time and generations. Notably, fitness landscapes that relate environmental cyclicality and life history optimality vary dramatically depending on which trade-offs govern a given species. The model tuned with known life history trade-offs in a marine intertidal copepod T. californicus successfully predicted the shape of life history variation across natural populations spanning a gradient of tidal periodicities. This framework shows how environmental cycles can drive life history variation—without complex assumptions of individual responses to cues such as temperature—thus expanding the range of life history diversity explained by theory and providing a basis for adaptive phenology.

Sign in / Sign up

Export Citation Format

Share Document