Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
1.
Conserv Physiol ; 12(1): coae013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38666227

RESUMO

Fluctuating ocean conditions are rearranging whole networks of marine communities-from individual-level physiological thresholds to ecosystem function. Physiological studies support predictions from individual-level responses (biochemical, cellular, tissue, respiratory potential) based on laboratory experiments. The otolith-isotope method of recovering field metabolic rate has recently filled a gap for the bony fishes, linking otolith stable isotope composition to in situ oxygen consumption and experienced temperature estimates. Here, we review the otolith-isotope method focusing on the biochemical and physiological processes that yield estimates of field metabolic rate. We identify a multidisciplinary pathway in the application of this method, providing concrete research goals (field, modeling) aimed at linking individual-level physiological data to higher levels of biological organization. We hope that this review will provide researchers with a transdisciplinary 'roadmap', guiding the use of the otolith-isotope method to bridge the gap between individual-level physiology, observational field studies, and modeling efforts, while ensuring that in situ data is central in marine policy-making aimed at mitigating climatic and anthropogenic threats.

2.
Biology (Basel) ; 13(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38666836

RESUMO

Antarctic marine ectotherms live in the constant cold and are characterised by limited resilience to elevated temperature. Here we tested three of the central paradigms underlying this resilience. Firstly, we assessed the ability of eight species, from seven classes representing a range of functional groups, to survive, for 100 to 303 days, at temperatures 0 to 4 °C above previously calculated long-term temperature limits. Survivors were then tested for acclimation responses to acute warming and acclimatisation, in the field, was tested in the seastar Odontaster validus collected in different years, seasons and locations within Antarctica. Finally, we tested the importance of oxygen limitation in controlling upper thermal limits. We found that four of 11 species studied were able to survive for more than 245 days (245-303 days) at higher than previously recorded temperatures, between 6 and 10 °C. Only survivors of the anemone Urticinopsis antarctica did not acclimate CTmax and there was no evidence of acclimatisation in O. validus. We found species-specific effects of mild hyperoxia (30% oxygen) on survival duration, which was extended (two species), not changed (four species) or reduced (one species), re-enforcing that oxygen limitation is not universal in dictating thermal survival thresholds. Thermal sensitivity is clearly the product of multiple ecological and physiological capacities, and this diversity of response needs further investigation and interpretation to improve our ability to predict future patterns of biodiversity.

3.
Cleft Palate Craniofac J ; : 10556656241241127, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38509820

RESUMO

BACKGROUND: Individuals with cleft lip and/or palate (CL/P) may grow up with a visible facial difference, alongside speech and/or hearing challenges. Self-perceptions are stronger predictors of psychosocial adjustment than objective assessments, highlighting the importance of patient-reported outcome measures. Previously titled the Satisfaction with Appearance (SwA) questionnaire, the Cleft Hearing, Appearance and Speech Questionnaire (CHASQ) has been used in several countries to assess patient satisfaction, guide clinical decision-making, and conduct craniofacial research, but has lacked general population norms from which to draw comparisons. The aim of this study was to contribute to the development of norms by utilising existing data collected in the United Kingdom (UK) in 2004 using the original SwA. METHODS: SwA data collected from school pupils (n = 761) aged 10-16 years were analysed across age and gender. RESULTS: Hair, Eyes and Ears received the highest ratings, while Teeth received the lowest ratings. Those who were younger, and those who were male, generally rated their appearance more favourably. Thresholds are proposed to identify young people in need of clinical monitoring (10%) and intervention (5%). DISCUSSION: This study supports the potential of the CHASQ as a clinically useful outcome measure and research tool with the ability to identify appearance concerns in relation to specific facial features, as well as overall appearance satisfaction in young people with and without CL/P. Further validation of its use in the CL/P population and other patient groups, as well as countries outside the UK would add additional weight to the CHASQ's utility.

4.
Nat Commun ; 15(1): 1822, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418445

RESUMO

Protection from direct human impacts can safeguard marine life, yet ocean warming crosses marine protected area boundaries. Here, we test whether protection offers resilience to marine heatwaves from local to network scales. We examine 71,269 timeseries of population abundances for 2269 reef fish species surveyed in 357 protected versus 747 open sites worldwide. We quantify the stability of reef fish abundance from populations to metacommunities, considering responses of species and functional diversity including thermal affinity of different trophic groups. Overall, protection mitigates adverse effects of marine heatwaves on fish abundance, community stability, asynchronous fluctuations and functional richness. We find that local stability is positively related to distance from centers of high human density only in protected areas. We provide evidence that networks of protected areas have persistent reef fish communities in warming oceans by maintaining large populations and promoting stability at different levels of biological organization.


Assuntos
Conservação dos Recursos Naturais , Peixes , Animais , Humanos , Peixes/fisiologia , Oceanos e Mares , Clima , Ecossistema , Recifes de Corais
5.
Med Sci Sports Exerc ; 56(4): 663-672, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37962224

RESUMO

PURPOSE: This study aimed to compare the responsiveness of patient-reported and device-based instruments within four physical activity trials. METHODS: This was a secondary analysis of four randomized trials that used both a patient-reported outcome measure (the Incidental and Planned Exercise Questionnaire (IPEQ)) and a device-based instrument (ActiGraph or ActivPAL) to measure physical activity. The four trials included were (i) Activity and MObility UsiNg Technology (AMOUNT), digitally enabled exercises in those undertaking aged care and neurological rehabilitation; (ii) Balance Exercise Strength Training at Home, home-based balance and strength exercises in community-dwelling people 65 yr or older; (iii) Coaching for Healthy Ageing (CHAnGE), physical activity coaching and fall prevention intervention in community-dwelling people 60 yr or older; and (iv) Fitbit trial, fall prevention and physical activity promotion with health coaching and activity monitor in community-dwelling people 60 yr or older. We estimated treatment effects for all variables within each physical activity instrument using regression analyses and expressed results as effect sizes (ES). RESULTS: Overall, device-based instruments were more responsive among healthy older adults (ES range, 0.01 to 0.32), whereas the IPEQ was more responsive among adults requiring rehabilitation (ES range, -0.06 to 0.35). Both the IPEQ and device-based instruments were more responsive in trials that promoted walking via coaching participants to increase their daily steps (AMOUNT (ES range, -0.06 to 0.35), CHAnGE (ES range, -0.24 to 0.22), and Fitbit trial (ES range, -0.23 to 0.32)). Individual variables within the IPEQ and device-based instruments varied in their responsiveness (ES range, -0.13 to 0.20). CONCLUSIONS: Both the IPEQ and device-based instruments are able to detect small changes in physical activity levels. However, responsiveness varies across different interventions and populations. Our findings provide guidance for researchers and clinicians in selecting an appropriate instrument to measure changes in physical activity.


Assuntos
Exercício Físico , Treinamento Resistido , Idoso , Humanos , Terapia por Exercício , Ensaios Clínicos Controlados Aleatórios como Assunto , Caminhada , Pessoa de Meia-Idade
7.
Cleft Palate Craniofac J ; : 10556656231211684, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37933127

RESUMO

Although the value of diversity within academia and society is increasingly recognised, the role of speakers with lived experience at cleft and craniofacial conferences remains inconsistent. This perspectives article shares reflection from three academics with lived experience of cleft discussing the value of including lived experience speakers routinely within conferences and outlining common challenges and barriers to the involvement of "experts-by-experience". Key considerations and recommendations are offered to help conference organisers and delegates to make the most of the lived experience perspective, while ensuring the conference experience is positive for lived experience speakers.

8.
Science ; 381(6662): 1067-1071, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37676959

RESUMO

Biotic responses to global change include directional shifts in organismal traits. Body size, an integrative trait that determines demographic rates and ecosystem functions, is thought to be shrinking in the Anthropocene. Here, we assessed the prevalence of body size change in six taxon groups across 5025 assemblage time series spanning 1960 to 2020. Using the Price equation to partition this change into within-species body size versus compositional changes, we detected prevailing decreases in body size through time driven primarily by fish, with more variable patterns in other taxa. We found that change in assemblage composition contributes more to body size changes than within-species trends, but both components show substantial variation in magnitude and direction. The biomass of assemblages remains quite stable as decreases in body size trade off with increases in abundance.


Assuntos
Biomassa , Tamanho Corporal , Animais , Fenótipo , Fatores de Tempo
10.
Conserv Physiol ; 11(1): coad027, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37179705

RESUMO

Winter at high latitudes is characterized by low temperatures, dampened light levels and short photoperiods which shape ecological and evolutionary outcomes from cells to populations to ecosystems. Advances in our understanding of winter biological processes (spanning physiology, behaviour and ecology) highlight that biodiversity threats (e.g. climate change driven shifts in reproductive windows) may interact with winter conditions, leading to greater ecological impacts. As such, conservation and management strategies that consider winter processes and their consequences on biological mechanisms may lead to greater resilience of high altitude and latitude ecosystems. Here, we use well-established threat and action taxonomies produced by the International Union of Conservation of Nature-Conservation Measures Partnership (IUCN-CMP) to synthesize current threats to biota that emerge during, or as the result of, winter processes then discuss targeted management approaches for winter-based conservation. We demonstrate the importance of considering winter when identifying threats to biodiversity and deciding on appropriate management strategies across species and ecosystems. We confirm our expectation that threats are prevalent during the winter and are especially important considering the physiologically challenging conditions that winter presents. Moreover, our findings emphasize that climate change and winter-related constraints on organisms will intersect with other stressors to potentially magnify threats and further complicate management. Though conservation and management practices are less commonly considered during the winter season, we identified several potential or already realized applications relevant to winter that could be beneficial. Many of the examples are quite recent, suggesting a potential turning point for applied winter biology. This growing body of literature is promising but we submit that more research is needed to identify and address threats to wintering biota for targeted and proactive conservation. We suggest that management decisions consider the importance of winter and incorporate winter specific strategies for holistic and mechanistic conservation and resource management.

11.
J Perinat Neonatal Nurs ; 37(2): 153-163, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37102563

RESUMO

AIMS: The aims of this project were to improve the utilization of developmental care practices in the neonatal unit and to increase opportunities for parental involvement in the planning and provision of caregiving. METHODS: This implementation project was conducted in a 79-bed neonatal tertiary referral unit in Australia. A pre/postimplementation survey design was utilized. A preimplementation survey was conducted to collect data on staff's perceived perception of developmental care practices. Following analysis of the data, a process for multidisciplinary developmental care rounds was developed and then implemented across the neonatal unit. A postimplementation survey was then conducted to evaluate whether staff perceived any changes in developmental care practices. The project was conducted over 8 months. RESULTS: A total of 97 surveys (pre: n = 46/post: n = 51) were received. Differences were demonstrated in staff's perceived perception of developmental care practices between the pre- and postimplementation periods in 6 themes of developmental care practice. Identified areas of improvement included the use of the 5-step dialogue, encouragement of parents to contribute to care planning, availability of a well-defined care plan for parents to visualize and document caregiving activities, increased use of swaddled bathing, side-lying position for nappy changes, consideration of infants sleep state before caregiving, and increased use of skin-to-skin therapy for management of procedural pain. CONCLUSION: Despite the majority of staff members who participated in both surveys acknowledging the importance of family-centered developmental care practice on neonatal outcomes, their use in clinical care is not always considered or practiced. Although it is reassuring to see improvements in several areas of developmental care postimplementation of the developmental care rounds, continued awareness and reinforcement of developmental neuroprotective caregiving strategies through initiatives such as a multidisciplinary care rounds are warranted.


Assuntos
Unidades de Terapia Intensiva Neonatal , Pais , Recém-Nascido , Lactente , Humanos , Inquéritos e Questionários , Austrália
12.
J Fish Biol ; 102(5): 1000-1016, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36880500

RESUMO

Critical thermal maxima methodology (CTM) has been used to infer acute upper thermal tolerance in fishes since the 1950s, yet its ecological relevance remains debated. In this study, the authors synthesize evidence to identify methodological concerns and common misconceptions that have limited the interpretation of critical thermal maximum (CTmax ; value for an individual fish during one trial) in ecological and evolutionary studies of fishes. They identified limitations of, and opportunities for, using CTmax as a metric in experiments, focusing on rates of thermal ramping, acclimation regimes, thermal safety margins, methodological endpoints, links to performance traits and repeatability. Care must be taken when interpreting CTM in ecological contexts, because the protocol was originally designed for ecotoxicological research with standardized methods to facilitate comparisons within study individuals, across species and contexts. CTM can, however, be used in ecological contexts to predict impacts of environmental warming, but only if parameters influencing thermal limits, such as acclimation temperature or rate of thermal ramping, are taken into account. Applications can include mitigating the effects of climate change, informing infrastructure planning or modelling species distribution, adaptation and/or performance in response to climate-related temperature change. The authors' synthesis points to several key directions for future research that will further aid the application and interpretation of CTM data in ecological contexts.


Assuntos
Aclimatação , Peixes , Animais , Peixes/fisiologia , Temperatura , Aclimatação/fisiologia , Evolução Biológica , Adaptação Fisiológica , Mudança Climática
13.
Nature ; 615(7954): 858-865, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36949201

RESUMO

Human society is dependent on nature1,2, but whether our ecological foundations are at risk remains unknown in the absence of systematic monitoring of species' populations3. Knowledge of species fluctuations is particularly inadequate in the marine realm4. Here we assess the population trends of 1,057 common shallow reef species from multiple phyla at 1,636 sites around Australia over the past decade. Most populations decreased over this period, including many tropical fishes, temperate invertebrates (particularly echinoderms) and southwestern Australian macroalgae, whereas coral populations remained relatively stable. Population declines typically followed heatwave years, when local water temperatures were more than 0.5 °C above temperatures in 2008. Following heatwaves5,6, species abundances generally tended to decline near warm range edges, and increase near cool range edges. More than 30% of shallow invertebrate species in cool latitudes exhibited high extinction risk, with rapidly declining populations trapped by deep ocean barriers, preventing poleward retreat as temperatures rise. Greater conservation effort is needed to safeguard temperate marine ecosystems, which are disproportionately threatened and include species with deep evolutionary roots. Fundamental among such efforts, and broader societal needs to efficiently adapt to interacting anthropogenic and natural pressures, is greatly expanded monitoring of species' population trends7,8.


Assuntos
Antozoários , Recifes de Corais , Calor Extremo , Peixes , Aquecimento Global , Invertebrados , Oceanos e Mares , Água do Mar , Alga Marinha , Animais , Austrália , Peixes/classificação , Invertebrados/classificação , Aquecimento Global/estatística & dados numéricos , Alga Marinha/classificação , Dinâmica Populacional , Densidade Demográfica , Água do Mar/análise , Extinção Biológica , Conservação dos Recursos Naturais/tendências , Equinodermos/classificação
14.
Biol Rev Camb Philos Soc ; 98(1): 1-18, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36054431

RESUMO

All animals on Earth compete for free energy, which is acquired, assimilated, and ultimately allocated to growth and reproduction. Competition is strongest within communities of sympatric, ecologically similar animals of roughly equal size (i.e. horizontal communities), which are often the focus of traditional community ecology. The replacement of taxonomic identities with functional traits has improved our ability to decipher the ecological dynamics that govern the assembly and functioning of animal communities. Yet, the use of low-resolution and taxonomically idiosyncratic traits in animals may have hampered progress to date. An animal's metabolic rate (MR) determines the costs of basic organismal processes and activities, thus linking major aspects of the multifaceted constructs of ecological niches (where, when, and how energy is obtained) and ecological fitness (how much energy is accumulated and passed on to future generations). We review evidence from organismal physiology to large-scale analyses across the tree of life to propose that MR gives rise to a group of meaningful functional traits - resting metabolic rate (RMR), maximum metabolic rate (MMR), and aerobic scope (AS) - that may permit an improved quantification of the energetic basis of species coexistence and, ultimately, the assembly and functioning of animal communities. Specifically, metabolic traits integrate across a variety of typical trait proxies for energy acquisition and allocation in animals (e.g. body size, diet, mobility, life history, habitat use), to yield a smaller suite of continuous quantities that: (1) can be precisely measured for individuals in a standardized fashion; and (2) apply to all animals regardless of their body plan, habitat, or taxonomic affiliation. While integrating metabolic traits into animal community ecology is neither a panacea to disentangling the nuanced effects of biological differences on animal community structure and functioning, nor without challenges, a small number of studies across different taxa suggest that MR may serve as a useful proxy for the energetic basis of competition in animals. Thus, the application of MR traits for animal communities can lead to a more general understanding of community assembly and functioning, enhance our ability to trace eco-evolutionary dynamics from genotypes to phenotypes (and vice versa), and help predict the responses of animal communities to environmental change. While trait-based ecology has improved our knowledge of animal communities to date, a more explicit energetic lens via the integration of metabolic traits may further strengthen the existing framework.


Assuntos
Biodiversidade , Ecossistema , Animais , Ecologia , Evolução Biológica , Fenótipo
15.
Curr Biol ; 32(19): 4128-4138.e3, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36150387

RESUMO

Warming seas, marine heatwaves, and habitat degradation are increasingly widespread phenomena affecting marine biodiversity, yet our understanding of their broader impacts is largely derived from collective insights from independent localized studies. Insufficient systematic broadscale monitoring limits our understanding of the true extent of these impacts and our capacity to track these at scales relevant to national policies and international agreements. Using an extensive time series of co-located reef fish community structure and habitat data spanning 12 years and the entire Australian continent, we found that reef fish community responses to changing temperatures and habitats are dynamic and widespread but regionally patchy. Shifts in composition and abundance of the fish community often occurred within 2 years of environmental or habitat change, although the relative importance of these two mechanisms of climate impact tended to differ between tropical and temperate zones. The clearest of these changes on temperate and subtropical reefs were temperature related, with responses measured by the reef fish thermal index indicating reshuffling according to the thermal affinities of species present. On low latitude coral reefs, the community generalization index indicated shifting dominance of habitat generalist fishes through time, concurrent with changing coral cover. Our results emphasize the importance of maintaining local ecological detail when scaling up datasets to inform national policies and global biodiversity targets. Scaled-up ecological monitoring is needed to discriminate among increasingly diverse drivers of large-scale biodiversity change and better connect presently disjointed systems of biodiversity observation, indicator research, and governance.


Assuntos
Antozoários , Recifes de Corais , Animais , Antozoários/fisiologia , Austrália , Biodiversidade , Mudança Climática , Ecossistema , Peixes/fisiologia
16.
Nat Ecol Evol ; 6(6): 684-692, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35449460

RESUMO

Diet and body mass are inextricably linked in vertebrates: while herbivores and carnivores have converged on much larger sizes, invertivores and omnivores are, on average, much smaller, leading to a roughly U-shaped relationship between body size and trophic guild. Although this U-shaped trophic-size structure is well documented in extant terrestrial mammals, whether this pattern manifests across diverse vertebrate clades and biomes is unknown. Moreover, emergence of the U-shape over geological time and future persistence are unknown. Here we compiled a comprehensive dataset of diet and body size spanning several vertebrate classes and show that the U-shaped pattern is taxonomically and biogeographically universal in modern vertebrate groups, except for marine mammals and seabirds. We further found that, for terrestrial mammals, this U-shape emerged by the Palaeocene and has thus persisted for at least 66 million years. Yet disruption of this fundamental trophic-size structure in mammals appears likely in the next century, based on projected extinctions. Actions to prevent declines in the largest animals will sustain the functioning of Earth's wild ecosystems and biomass energy distributions that have persisted through deep time.


Assuntos
Ecossistema , Vertebrados , Animais , Tamanho Corporal , Herbivoria , Mamíferos
17.
BMC Geriatr ; 22(1): 366, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473594

RESUMO

BACKGROUND: Falls are a significant public health issue. There is strong evidence that exercise can prevent falls and the most effective programs are those that primarily involve balance and functional exercises, however uptake of such programs is low. Exercise prescribed during home visits by health professionals can prevent falls however this strategy would be costly to deliver at scale. We developed a new approach to teach home exercise through group-based workshops delivered by physiotherapists. The primary aim was to determine the effect of this approach on the rate of falls among older community-dwelling people over 12 months. Secondary outcomes included the proportion of people falling, fear of falling, physical activity, lower limb strength, balance and quality of life. METHODS: A randomised controlled trial was conducted among community-dwelling people aged ≥65 in New South Wales, Australia. Participants were randomised to either the intervention group (exercise targeting balance and lower limb strength) or control group (exercise targeting upper limb strength). RESULTS: A total of 617 participants (mean age 73 years, +SD 6, 64% female) were randomly assigned to the intervention group (n = 307) or control group (n = 310). There was no significant between-group difference in the rate of falls (IRR 0.91, 95% CI 0.64 to 1.29, n = 579, p = 0.604) or the number of participants reporting one or more falls (IRR 0.99, 95% CI 0.76 to 1.29, n = 579, p = 0.946) during 12 month follow-up. A significant improvement in the intervention group compared to control group was found for fear of falling at 3, 6 and 12 months (mean difference 0.50, 95% CI 0.2 to 0.8, p = 0.004; 0.39, 95% CI 0.001 to 0.8, p = 0.049; 0.46, 95% CI 0.006 to 0.9, p = 0.047, respectively), and gait speed at 3 months (mean difference 0.09 s, 95% CI 0.003 to 0.19, p = 0.043). No statistically significant between-group differences were detected for the other secondary outcomes. CONCLUSIONS: There was no significant intervention impact on the rate of falls, but the program significantly reduced fear of falling and improved gait speed. Other exercise delivery approaches are needed to ensure an adequate intensity of balance and strength challenge and dose of exercise to prevent falls.


Assuntos
Acidentes por Quedas , Vida Independente , Acidentes por Quedas/prevenção & controle , Idoso , Terapia por Exercício , Medo , Feminino , Humanos , Masculino , Qualidade de Vida
18.
J Paediatr Child Health ; 58(1): 163-169, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34448317

RESUMO

AIM: The delivery room intubation rate for babies born less than 32 weeks postmenstrual age (PMA) at the Mater Mothers' Hospital in 2017 was 51%. Delivery room intubation of preterm infants may be associated with an increased risk of developing bronchopulmonary dysplasia. This quality improvement project aimed to decrease the rate of delivery room intubation for infants born less than 32 weeks PMA. METHODS: A quality improvement process using the evidence-based practice for improving quality framework and Plan-Do-Study-Act cycles was undertaken from October 2018 to December 2019. Commencing bubble continuous positive airway pressure for initial resuscitation in the delivery room was the principal change idea. RESULTS: The delivery room intubation rate for infants born less than 32 weeks PMA before the commencement of this project was 48% (cohort 1, n = 221). There was a significant decrease in the rate to 37.2% while the project was being conducted (cohort 2, n = 277) and a further significant reduction to 28.2% after introducing bubble continuous positive airway pressure in the delivery room (cohort 3, n = 202). There was a significant improvement in admission temperatures and a significant decrease in mortality rate between cohort 1 and cohort 2 but not between cohort 2 and cohort 3. There was no change in the rate of discharge home on oxygen between cohorts. CONCLUSIONS: This quality improvement project led to a significantly decreased delivery room intubation rate in infants born less than 32 weeks PMA. There was no evidence of any adverse outcomes with this approach.


Assuntos
Displasia Broncopulmonar , Salas de Parto , Pressão Positiva Contínua nas Vias Aéreas , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Intubação Intratraqueal , Gravidez , Melhoria de Qualidade
19.
Sci Total Environ ; 806(Pt 4): 150943, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655637

RESUMO

Physiological comparisons are fundamental to quantitative assessments of the capacity of species to persist within their current distribution and to predict their rates of redistribution in response to climate change. Yet, the degree to which physiological traits are conserved through evolutionary history may fundamentally constrain the capacity for species to adapt and shift their geographic range. Taxa that straddle major climate transitions provide the opportunity to test the mechanisms underlying evolutionary constraints and how such constraints may influence range shift predictions. Here we focus on two abundant and shallow water nacellid limpets which have representative species on either side of the Polar front. We test the thermal thresholds of the Southern Patagonian limpet, Nacella deaurata and show that its optimal temperatures for growth (4 °C), activity (-1.2 to -0.2 °C) and survival (1 to 8 °C) are mismatched to its currently experienced annual sea surface temperature range (5.9 to 10 °C). Comparisons with the congeneric Antarctic limpet, N. concinna, reveal an evolutionary constraint on N. deaurata physiology, with overlapping thermal capacities, suggesting that a cold climate legacy has been maintained through the evolution of these species. These physiological assessments predict that the South American range of N. deaurata will likely decline with continued warming. It is, however, one of the first species with demonstrated physiological capacity to successfully colonize the cold Southern Ocean. With the expected increase in opportunities for transport within high southern latitudes, N. deaurata has the potential to establish and drive ecological change within the shallow Southern Ocean.


Assuntos
Gastrópodes , Animais , Regiões Antárticas , Mudança Climática , Temperatura Baixa , Temperatura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...