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Aspectos evolutivos da história de vida e estrutura da casca do ovo de lagartos tropiduríneos; Evolutive aspects of life history and eggshell morphology of Tropidurinae lizards

Nunes, Renata Brandt
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/08/2010 PT
Relevância na Pesquisa
66%
Em lagartos, componentes de história de vida apresentam grande plasticidade fenotípica e evoluem de maneira correlacionada. O número de ovos, por exemplo, tende a ser correlacionado positivamente com o tamanho corpóreo das fêmeas grávidas, tanto em linhagens evolutivas quanto entre indivíduos, embora alguns tipos de hábito pareçam restringir ninhadas maiores. Há indícios de que outros fatores, como componentes climáticos, ou latitude, também sejam determinantes das características de história de vida do grupo, tanto por questões de fisiologia termal quanto ecológicas. Componentes climáticos influenciam ainda diferentes aspectos da reprodução em lagartos, como por exemplo a estrutura e morfologia da casca dos ovos de Squamata, conforme indicam diferenças nestas características entre linhagens de lagartos ovíparos. Neste contexto, o presente trabalho investigou aspectos evolutivos da história de vida de lagartos da subfamília Tropidurinae, e sua relação com componentes climáticos e latitude, através de métodos filogenéticos comparativos. Observou-se que o número de ovos da ninhada é positivamente correlacionado com o tamanho corpóreo ao longo da linhagem dos tropiduríneos. Por outro lado, esse padrão não é observado no caso de hábito escansorial e utilização de frestas de rochas...

The amphipod Corophium multisetosum (Corophiidae) in Ria de Aveiro (NW Portugal). I. Life history and aspects of reproductive biology

Cunha, M. R.; Sorbe, J. C.; Moreira, M. H.
Fonte: Springer Verlag Publicador: Springer Verlag
Tipo: Artigo de Revista Científica
ENG
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65.98%
The population of Corophium multisetosum Stock, 1952 in Areao displayed a semiannual, iteroparous life history. Mean longevity was similar to6 mo, with the estimated life span longer for overwintering individuals born in autumn than for individuals born in spring. Length-frequency data indicated that the length increment per moult is probably higher in males than females; however females moulted more frequently and achieved a larger body size. Preliminary growth rates were 100 mum d(-1) for juveniles and 19 to 29 mum d(-1) for mature females, with the lower values occurring during the winter. It was estimated that under favourable conditions females may attain reproductive size and mature within 1 mo. Although incubating females were present all year round, recruitment occurred in spring, almost ceased during the summer, peaked in autumn, and decreased again during the winter. Extreme temperatures and very low salinities during winter and summer may have deterred breeding, while moderate temperatures (15 to 20 degreesC) and salinities >1 psu in spring and autumn were apparently favourable for reproduction. The unfavourable summer conditions constrained breeding and synchronised the timing of reproduction. In late-autumn and during the winter...

Prey availability in time and space is a driving force in life history evolution of predatory insects

Borges, Isabel; Soares, António O.; Magro, Alexandra; Hemptinne, Jean-Louis
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
Publicado em 21/04/2011 ENG
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Copyright © 2011 Springer Science+Business Media B.V..; Environmental constraints can be determinant key factors conditioning predator life history evolution. Prey seems to have conditioned life history evolution in their ladybird predator, with the predators of aphids apparently presenting faster development, greater fecundity and shorter longevity than species preying on coccids. However a rigorous comparison has never been done. We hypothesize that aphids and coccids differ by their developmental rate, abundance, and distribution in the field, which act as ecological constraints promoting life history evolution in ladybird predators. Field data reveal that aphids are ephemeral resources available in the form of large colonies randomly distributed in the habitat whereas coccids form smaller colonies that tend to be aggregated in space and available for longer periods. A comparison in laboratory conditions of two predatory species belonging to the tribe Scymnini (Coleoptera: Coccinellidae) show that the aphidophagous species lives at a faster pace than the coccidophagous: it develops faster, matures earlier, is more fecund, has a shorter reproductive life-span and allocate proportionally more fat in its gonads relative to soma. This indicates that the life histories of aphidophagous and coccidophagous ladybird predators appear to have evolved in response to particular patterns of prey availability in time and space. Under the light of these results...

Age and growth of three Odontesthes species from Southern Brazil (Atherinopsidae), with reference to phylogenetic constraints in their life-history

Becker,F. G.; Bruschi Jr.,W.; Peret,A. C.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2003 EN
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The age and growth of three silverside species are described, and a discussion on possible phylogenetic constraints on life-history characteristics is presented. Samples were collected monthly between March 1992 and February 1993 in three freshwater coastal lakes. Standard length-total length (Ls-Lt) and weight-length (Wt-Lt) relationships studied showed interspecific differences in comparisons between juveniles and adults, males and females. Age was determined by scales. The three species presented a life-cycle duration of 4 to 5 years, with growth coefficients values (K) between 0.37 and 0.63, and asymptotic lengths between 211 and 257 mm. Some interspecific differences may be useful for distinguishing between species (sexual and life-stage related patterns in Ls-Lt and Wt-Lt). The observed life-cycle ranges and maximum sizes were compared to those of other silversides and revealed a pattern coherent with available phylogenetic hypotheses at the supra-generic level, indicating that some life-history characteristics may be subject to phylogenetic constraints.

Soil factors effects on life history attributes of Leiothrix spiralis and Leiothrix vivipara (Eriocaulaceae) on rupestrian grasslands in Southeastern Brazil

Coelho,FF; Martins,RP; Figueira,JEC; Demetrio,GR
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2014 EN
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In this study, we hypothesized that the life history traits of Leiothrix spiralis and L. vivipara would be linked to soil factors of the rupestrian grasslands and that rosette size would be influenced by soil moisture. Soil analyses were performed from five populations of L. spiralis and four populations of L. vivipara. In each area, three replicates were employed in 19 areas of occurrence of Leiothrix species, and we quantified the life history attributes. The microhabitats of these species show low favorability regarding to soil factors. During the dry season, their rosettes decreased in diameter due the loss of its most outlying leaves. The absence of seedlings indicated the low fecundity of both species. However, both species showed rapid population growth by pseudovivipary. Both L. spiralis and L. vivipara exhibit a kind of parental care that was quantified by the presence of connections between parental-rosettes and ramets. The findings of the present study show that the life history traits are linked to soil factors.

Functional Linkages for the Pace of Life, Life-history, and Environment in Birds

Williams, Joseph B.; Miller, Richard A.; Harper, James M.; Wiersma, Popko
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
EN
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66.02%
For vertebrates, body mass underlies much of the variation in metabolism, but among animals of the same body mass, metabolism varies six-fold. Understanding how natural selection can influence variation in metabolism remains a central focus of Physiological Ecologists. Life-history theory postulates that many physiological traits, such as metabolism, may be understood in terms of key maturational and reproductive characteristics over an organism’s life-span. Although it is widely acknowledged that physiological processes serve as a foundation for life-history trade-offs, the physiological mechanisms that underlie the diversification of life-histories remain elusive. Data show that tropical birds have a reduced basal metabolism (BMR), field metabolic rate, and peak metabolic rate compared with temperate counterparts, results consistent with the idea that a low mortality, and therefore increased longevity, and low productivity is associated with low mass-specific metabolic rate. Mass-adjusted BMR of tropical and temperate birds was associated with survival rate, in accordance with the view that animals with a slow pace of life tend to have increased life spans. To understand the mechanisms responsible for a reduced rate of metabolism in tropical birds compared with temperate species...

Pooled Energy Budget and Human Life History

Duncan, Laura G.; Gardiner, Eliza; Sharrock, Katherine C.; Lipson, Susan F.; Ellison, Peter; Reiches, Meredith W.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
EN_US
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65.98%
Human life history contains a series of paradoxes not easily explained by classical life history theory. While overall reproductive output is higher than in related primates, juvenile growth is slower and age-specific reproductive rates decline faster with age. A simple energetic model would predict that growth and reproductive rates should be positively correlated and that reproductive effort should not decelerate with age. The pattern of negative correlations in humans suggests the presence of trade-offs among peak reproductive rate, childhood growth, and reproductive rate at older ages. To address this puzzle, we propose a synthesis of reproductive ecology and behavioral ecology focused on intra- and inter-somatic energy transfers. This integration includes three concepts: the mother as final common pathway through which energy must pass to result in offspring; a distinction between direct and indirect reproductive effort, proposing the latter as a novel net energy allocation category relative to growth and direct reproductive effort; and a pooled energy budget representing the energetic contributions and withdrawals of all members of a breeding community. Individuals at all reproductive life stages are considered in light of their contributions to the pooled energy budget. This is a preprint of an article accepted for publication in The American Journal of Human Biology © 2009 Peter T. Ellison; Anthropology; Human Evolutionary Biology

The Influence of Phenotypic Plasticity and Life History Trade-offs on Zooplankton Hemoglobin Production

Gauld, Jillian
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
66.08%
Temperate freshwater lake systems often exhibit a dramatic oxygen gradient throughout the summer months, within which many zooplankton species live and migrate. The production of hemoglobin is the primary adaptation to hypoxic stress in a genus of zooplankton, Daphnia, but causes a decrease in energy used for other physical processes. The capacity for hemoglobin production in hypoxia has been shown to differ between genotypes, but no studies have examined the variation in production between genotypes across a gradient of oxygen conditions. My study aims to determine the life history consequences of hemoglobin production in Daphnia pulicaria, as well as compare the influence of genetics and anoxic stress on hemoglobin production. A significant influence of oxygen concentration on hemoglobin production, fecundity, and age at death was found, but no differences between isofemale lines were noted except for fecundity measurements. No significant correlation was found between hemoglobin production and the life history traits measured, across genotypes and oxygen treatments. Within each oxygen treatment, a positive correlation for age at death and a negative correlation for fecundity were found found at medium to high oxygen treatments of 1.5 and 6 mg/L O2...

The influence of temperature on growth, developmental time and life history traits of Adoxophyes honmai

Evans, Michael
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
66%
In biology, external factors such as temperature, pH, and humidity can affect plants and animals by altering their behaviour, anatomy, development, or biochemistry. Ectothermic species, which often regulate their bodies based on ambient conditions, are known to be sensitive to seasonal changes in temperature as their life history traits are altered. In Japan, a tortrix moth species known as Adoxophyes honmai commonly infests tea crops and can cause vast economic damage. Research directed at understanding their outbreaks and controlling their numbers has recently been on the rise. These large amplitude outbreaks occur during the summer rather than the winter, and therefore it has been postulated that seasonal temperature influences their life history through development. An increased growth rate on an individual scale often translates to larger and denser populations at a population scale. In this thesis, the effect of temperature on individual growth rates, pupal mass, time to pupation and adult longevity were examined. The experiment consisted of trials containing an independent larva isolated in a vial; there were five temperature trials and thirty replicates for each ranging from 17-29°C, in 3°C increments. It was found that there was a significant effect of temperature on larval growth rate...

Genotypic differences and life-history trade-offs in the freshwater zooplankton, Daphnia pulicaria, under natural levels of food limitation

Olijnyk, Adriana Maria
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
66.14%
The schedule of growth, reproduction and survivorship of an individual are the key components of life history, which reflect fitness performance of a genotype. Examining the variation in life history performance among genotypes provides an avenue for which genotypic fitness differences can be compared. The parthenogenetic freshwater zooplankton, Daphnia pulicaria, is a model organism to investigate and disentangle the genotypic from the phenotypic influences of life history variation. While Daphnia spp. life history has been extensively studied, few have examined the effect of low food concentrations on life history traits. Since Daphnia spp. are frequently subjected to periods food limitation caused by natural phytoplankton cycles, it is necessary to understand how individuals respond in low food environments in order to obtain an accurate representation of life history responses among genotypes. In this study, I conducted a set of highly controlled laboratory experiments using multiple genotypes of Daphnia pulicaria under a range of food-limited conditions in order to gain insight into the environmental and genotypic responses of life history traits. I measured a suite of life history traits, growth, reproduction and survivorship...

Food Quality Effects On Life History Trait Correlations In Daphnia

Bengtson, Stefan
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
66.06%
Life history theory assumes that correlations among fitness-related life history traits should be negative among individuals, reflecting resource allocation constraints among traits such as growth and reproduction. These traits trade off because they cannot be simultaneously maximized in individuals facing finite resource acquisition. Positive correlations among traits that are expected to be negative (e.g. between energetically costly traits) have been regularly observed, however, and have usually been ascribed to genetic or resource acquisition differences. In the freshwater zooplankton Cladoceran Daphnia, positive correlations have been particularly well documented even when genetic and environmental variation have been controlled. The sign of these correlations represent a problem for life history theory, which is underpinned by the notion of universal and unavoidable costs associated with investing in a given trait. It has been suggested, however, that costs vary with environment and thus can change the sign of a correlation. A change in correlation sign over an environmental gradient may indicate that the assumed universality of costs and constraints are not as universal as expected by life history theory. Few life history experiments have examined traits in multiple environments...

Memorys of teachers: Helena Ferrari Teixeira’s life history; Memórias de professoras: a história de vida de Helena Ferrari Teixeira

Brancher, Vantoir Roberto; Universidade Federal de Santa Maria, Rio Grande do Sul; Oliveira, Valeska Fortes de
Fonte: Universidade Federal de Santa Maria Publicador: Universidade Federal de Santa Maria
Tipo: info:eu-repo/semantics/article; "Avaliados por pares"; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em 21/07/2010 POR
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Some aims of this research are to know and to analyze the Life History of a very singular teacher of significative importance to Brazillian Women’s History, Education and Politics. For (re)constructing her history, we adopted a qualitative methodology based on Life History Biographical Method in the Oral cathegory and also in other forms of documentation like newspapers, photographs, testimonies and other surveys already done. From this investigation, initially resulted some interviews with the contributor, which was been transcripted, analyzed and discussed under the scope of various references, like Genre, Memory, Oral History, Knowledge, etc. The (re)construction of Helena Ferrari Teixeira’s life history, the first woman in Santa Maria Legislature with great possibilities of being the first in Brazillian Legislature, she entered formally in politics in 1951, remaining for three consecutive mandates. We also found, in the family and/or public files a considerable number of documents and photographs of the teacher. Some considerations would be already pointed based on the first documentary researches we made, that provide us the possibility to realize and to understand the individuals nd respective social places taken by them. To observe the knowledge of the Teaching Helena Ferrari provides the reviewing of the places and spaces lived by teaching in different periods. From it...

The Fast-Slow Continuum in Mammalian Life History: An Empirical Reevaluation

Bielby, Jon; Mace, Georgina M; Bininda-Emonds, Olaf R. P.; Cardillo, Marcel; Gittleman, John L; Jones, Kate E.; Orme, C. David L.; Purvis, A.
Fonte: University of Chicago Press Publicador: University of Chicago Press
Tipo: Artigo de Revista Científica
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Many life-history traits co-vary across species, even when body size differences are controlled for. This phenomenon has led to the concept of a "fast-slow continuum," which has been influential in both empirical and theoretical studies of life-history ev

Life-history phenotypes in populations of Brachyrhaphis episcopi (Poeciliidae) with different predator communities

Jennions, Michael; Telford, S
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
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Variation among populations in extrinsic mortality schedules selects for different patterns of investment in key life-history traits. We compared life-history phenotypes among 12 populations of the live-bearing fish Brachyrhaphis episcopi. Five population

The life history and cell cycle of Kryptoperidinium foliaceum, a dinoflagellate with two Eukaryotic nuclei

Figueroa, Rosa Isabel; Bravo, Isabel; Fraga, Santiago; Garcés, Esther; Llaveria, Gisela
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 6039115 bytes; application/pdf
ENG
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6 pages, 10 figures.; Kryptoperidinium foliaceum is a binucleate dinoflagellate that contains an endosymbiont nucleus of diatom origin. However, it is unknown whether the binucleate condition is permanent or not and how the diatom nucleus behaves during the life history processes. In this sense, it is also unknown if there is a sexual cycle or a resting stage during the life history of this species, two key aspects necessary to understand the life history strategy of this dinoflagellate. To answer these questions, life history and cell cycle studies were performed with the following results: (i) Kryptoperidinium foliaceum has a sexual cycle and in the dinoflagellate strains studied, the binucleate condition is permanent. Sexuality in the host was confirmed by the presence of fusing gamete pairs and planozygotes in clonal cultures (revealing homothallism), but signs of meiosis in the endosymbiont were not observed. The endosymbiont nucleus likely fuses first, because fusing gamete pairs were found to have two dinoflagellate nuclei but only one endosymbiont nucleus. After complete gamete fusion, the planozygotes had apparently normal endosymbiont and dinoflagellate nuclei. (ii) Asexual division studies using flow cytometry showed that the S phase in the endosymbiont (diatom) nucleus starts 6–8 h later than in the host nucleus...

Reconstructing life history traits from bone histology in extant and fossil ruminants

Marín Moratalla, Miren Nekane
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2014 ENG
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El estudio de las life histories es de vital importancia porque proporciona evidencias sobre las condiciones ecológicas, biodiversidad, demografía, vulnerabilidad y otros muchos aspectos de la biología de las especies. La histología ósea es utilizada como herramienta para reconstruir las life histories de vertebrados, analizando el tejido óseo primario o contando el número de marcas de crecimiento (esqueletocronología). Sin embargo, se ha considerado que los endotermos, al contrario que en ectotermos, muestran un crecimiento óseo no cíclico, invalidando la histología ósea para inferir las life histories de mamíferos. El objetivo general de esta tesis es proporcionar las bases de la histología ósea en mamíferos para inferir estrategias de life history. Los objetivos concretos son: i) analizar la fiabilidad de la esqueletocronología ósea en mamíferos, ii) explorar la asociación entre las características del tejido óseo y el ambiente, fisiología, ontogenia y life history y, iii) reconstruir las características de life history en mamíferos fósiles y actuales para obtener datos sobre la evolución de las life histories y biología de la conservación. Se han analizado 274 láminas transversales de hueso de 225 individuos pertenecientes a lirones actuales (Gliridae) y rumiantes actuales y fósiles (Bovidae...

Evolutionary Relationship between Life History and Brain Growth in Anthropoid Primates

Barrickman, Nancy Lynn
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação Formato: 4935943 bytes; application/pdf
Publicado em 18/09/2008 EN_US
Relevância na Pesquisa
66.09%

The pace of life history is highly variable across mammals, and several evolutionary biologists have theorized that the tempo of a species' life history is set by external factors. These factors, such as food availability and predation pressure, determine mortality rates. In turn, mortality rate determines the age at maturity. High mortality rate results in early age at maturity; individuals must grow and reproduce quickly because of the high risk of death. Conversely, a low mortality rate is allows individuals to prolong their growth period and reproduce slowly. This theory assumes that growth rates are constant across species, and thus body size is determined by mortality rates.

This project posits that the intrinsic characteristics of species set the pace of life history. Among anthropoids, there is a great deal of variation in growth rates and the pace of life history relative to body size. The hypotheses proposed by this project state that the degree of encephalization in a species determines the growth rates, the length of the growth period, and the adult lifespan. Growing a large brain is costly and requires a prolonged period of development. However, a large brain has the benefit of reducing mortality by facilitating cognitive strategies for food procurement and predator avoidance. This cost/benefit balance results in the pattern of life-history variation in which mortality rates are correlated with the length of the growth period. However...

Life in the slow lane: Reproductive life history of the White-browed Scrubwren, an Australian endemic

Magrath, Robert D; Leedman, A; Gardner, Janet; Giannasca, A; Nathan, A; Yezerinac, S; Nicholls, James
Fonte: American Ornithologists Union Publicador: American Ornithologists Union
Tipo: Artigo de Revista Científica
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An understanding of geographic and phylogenetic variation in passerine life histories is hampered by the scarcity of studies from the Southern Hemisphere. We documented the breeding biology of the White-browed Scrubwren (Sericornis frontalis), an Australia endemic in the Pardalotidae (parvorder Corvida). Like other members of the Pardalotidae, scrubwrens had a long laying interval (two days), a long incubation period (declining from 21 to 17 days through the season), and a long period of postfledging parental care (6 to 7 weeks). Scrubwrens appeared to be typical of the Australian Corvida in having a small clutch size (three eggs) and a long breeding season (5.4 months), and they also had a long interval between breeding attempts (10 days after a failed attempt, 21 days after a successful attempt). Scrubwrens were multibrooded, often raising two broods successfully and occasionally raising three broods. The breeding biology of scrubwrens adds further support to claims of a distinct life-history strategy for members of the Corvida but also reinforces evidence that some 'Corvida' life-history traits more specifically are those of the Pardalotidae.

Life-history traits as causes or consequences of social behaviour: why do cooperative breeders lay small clutches?

Hardling, Roger; Kokko, Hanna
Fonte: Evolutionary Ecology Ltd Publicador: Evolutionary Ecology Ltd
Tipo: Artigo de Revista Científica
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66.03%
Cooperatively breeding birds tend to exhibit high adult survival and relatively small clutch sizes. According to the life-history hypothesis for cooperative breeding, high survival creates conditions for philopatry based on difficulties that dispersers face when competing for territories in a landscape with slow territory turnover. However, this hypothesis evokes a puzzle because high fecundity should also lead to problems in territory acquisition because of the large number of competitors for each vacancy. We suggest two reasons for the observed association between small clutch size, high survival rate and cooperative breeding in birds. The first reason is that when survival rate is a better predictor of cooperative breeding than fecundity, a general life-history trade-off between clutch size and survival rate will create the observed association between cooperative breeding and the two life-history characters. Theoretically, a high survival rate is expected to predict cooperative breeding better than fecundity, because a high survival rate increases both habitat saturation and the direct benefits of staying at home. The second reason is that the reproductive value of the first offspring each year is higher than that of subsequent offspring for cooperative breeders (the offspring depreciation hypothesis). This is because these offspring will be able to delay dispersal and gain indirect benefits by helping at home. We show that this...

Tracing the life history of individual Barramundi using laser ablation MC-ICP-MS Sr-isotopic and Sr/Ba ratios in otoliths

McCulloch, Malcolm; Cappo, Mike; Aumend, James; Mueller, Wolfgang
Fonte: CSLI Publications Publicador: CSLI Publications
Tipo: Artigo de Revista Científica
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Otoliths preserve a continuous geochemical record of its life history, from the earliest natal stage through to adulthood. Using in situ laser ablation (UV) multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) measurements of Sr isotopic compositions together with elemental abundances (Ca, Sr, Ba and Mg), we show how it is possible to characterise the various types of habitats encountered throughout the lifecycle history of individual barramundi. Unlike trace element concentrations, which can be modulated by physiological processes, Sr isotopic compositions of otoliths provide a direct fingerprint of the water mass in which the fish lived. Elemental abundances, in particular Sr/Ba ratios are, however, shown to be especially sensitive to transitional environments, such as estuaries. The flexibility of the barramundi's life history is confirmed by the present study, with the existence of both marine and freshwater nurseries, with some individuals spending their entire life cycle in fresh water, some entirely in marine and others moving between freshwater estuarine and marine habitats.