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2.
Artigo em Inglês | MEDLINE | ID: mdl-39122106

RESUMO

Body temperature (Tb) variation and environmental temperature gradients are more intense in small individuals because their body size allows for a more intimate relationship between Tb and the environment. To contribute to a methodological consensus on the ecophysiology of small ectotherms, we aimed to investigate whether different approaches and methodological techniques affect the measurement of critical temperatures in a small lizard (Coleodactylus meridionalis, Sphaerodactylidae) from the Atlantic Forest of southern Bahia, Brazil, and subsequently its vulnerability assessment. We measured two metrics of thermal physiology: critical thermal minimum (CTmin) and critical thermal maximum (CTmax). In total, four types of temperature measurements (protocols) were defined. In the first protocol, we estimated CTmax/CTmin without heating/cooling rate by directly measuring the lizard's midbody temperature. In the other three protocols, we used a ramping assay with a heating/cooling rate to estimate CTmax/CTmin in the chamber (height: 11.3 cm), substrate, and Tb of the lizard, respectively. In total 116 individuals of Coleodactylus meridionalis were collected, of which 177 CTmax and 131 CTmin were performed. C. meridionalis showed a mean CTmax of 41 °C and a mean CTmin of 8.9 °C when considering the Tb protocol, which is intermediate compared to the other protocols. The substrate temperature protocol was the closest to Tb, and for this, the best method for the small lizards using an infrared thermometer.

3.
An Acad Bras Cienc ; 96(3): e20230728, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38922256

RESUMO

The ecology of movement is an expanding area, marked by the diversity of analytical methods and protocols, which enables this integrative reading. We investigated movement ecology aspects of Coleodactylus meridionalis in southern Bahia, northeastern Brazil, using fluorescent powder with mineral oil to track individuals. We monitored 69 individuals of C. meridionalis that walked an average distance of 148 cm in 2h. We identified this movement as foraging due to the orientation of the step sequence and microenvironments used. We find no significant differences between walking distance and weight. However, we found a decrease in activity over the follow-up period. Most of the lizard's movements were directed north, while south, east, and west were followed equally. The individuals stayed predominantly on the ground (leaf litter), but it was possible to observe the use of other surfaces, such as trunks and burrows on the ground. Therefore, we studied the movement in three dimensions (ground height, distance traveled, and orientation of steps). We observed the lizard's foraging, one of the most common and least investigated movements in small lizards like C. meridionalis. This involves not only the species' activity schedule but other intrinsic and extrinsic factors that shape the movement decisions of individuals.


Assuntos
Lagartos , Animais , Lagartos/fisiologia , Lagartos/classificação , Brasil , Florestas , Pós , Masculino
6.
An Acad Bras Cienc ; 92(4): e20201292, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33146238

RESUMO

Since the beginning of the COVID-19 pandemic, publications have highlighted the disproportionate impact of the COVID-19 pandemic on academic mothers, mostly focusing on the impact of social distancing and quarantine. A few months later, despite the lack of effective vaccines or therapeutics in sight, many economic activities are being resumed. Nurseries and schools are expected to be among the latest to reopen, which will amplify the impacts of the pandemic on academic mothers. In this letter, we unwrap the pandemic impacts on academic mothers and describe a set of specific short-, medium- and long-term policies that, if implemented, could reduce setbacks for gender equality during the pandemic and can help to level the playing field for academic mothers.


Assuntos
Infecções por Coronavirus , Mães , Pandemias , Pneumonia Viral , Betacoronavirus , Brasil , COVID-19 , Feminino , Humanos , SARS-CoV-2
7.
Artigo em Inglês | MEDLINE | ID: mdl-31319170

RESUMO

The scarcity of data on natural history and ecology of lizards still limits the understanding of population dynamics for many species. We attempt to evaluate possible effects of climate change on the population dynamics of three lizard species (Ameiva ameiva, Gonatodes humeralis and Norops fuscoauratus) in two Amazonian localities (Caxiuanã National Forest and Ducke Reserve). We calculated a tolerance index combining environmental thermal adequacy with the b-d model, which consider survival and reproductive rates to calculate population dynamics. Thus, we simulated population growth rates based on current and future environmental operative temperatures, considering an optimistic and a business-as-usual scenario of greenhouse gases emissions (GGE), and evaluate if the sensitivity of life history traits to population growth rate are likely to be trigged by climate change. Our results demonstrated that both populations of G. humeralis and the Ducke population of N. fuscoauratus may become locally extinct under both scenarios of GGE, while both populations of A. ameiva are likely to decrease, but without reaching a scenario of local extirpation. This study represents the first effort to evaluate the sensitivity of lizard populations and elasticity to climate change and demonstrate the geographic variability of these traits in three widespread and habitat-generalist species. We highlight the need of new studies focusing on species with different biological trait patterns, such as endemic distributions and habitat-specialists, to provide the theoretical and empirical basis for biologically informed conservation strategies and actions, in order to minimize the potential extinction of populations due to climate change.


Assuntos
Mudança Climática , Lagartos/crescimento & desenvolvimento , Animais , Intervalos de Confiança , Dinâmica Populacional , América do Sul , Especificidade da Espécie
11.
J Therm Biol ; 78: 401-414, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30509664

RESUMO

In recent decades, changes in climate have caused impacts on natural and human systems on all continents and across the oceans and many species have shifted their geographic ranges, seasonal activities, migration patterns, abundances and interactions in response to these changes. Projections of future climate change are uncertain, but the Earth's warming is likely to exceed 4.8 °C by the end of 21th century. The vulnerability of a population, species, group or system due to climate change is a function of impact of the changes on the evaluated system (exposure and sensitivity) and adaptive capacity as a response to this impact, and the relationship between these elements will determine the degree of species vulnerability. Predicting the potential future risks to biodiversity caused by climate change has become an extremely active field of research, and several studies in the last two decades had focused on determining possible impacts of climate change on Lepidosaurians, at a global, regional and local level. Here we conducted a systematic review of published studies in order to seek to what extent the accumulated knowledge currently allow us to identify potential trends or patterns regarding climate change effects on lizards, snakes, amphisbaenians and tuatara. We conducted a literature search among online literature databases/catalogues and recorded 255 studies addressing the influence of climate change on a total of 1918 species among 49 Lepidosaurian's families. The first study addressing this subject is dated 1999. Most of the studies focused on species distribution, followed by thermal biology, reproductive biology, behavior and genetics. We concluded that an integrative approach including most of these characteristics and also bioclimatic and environmental variables, may lead to consistent and truly effective strategies for species conservation, aiming to buffer the climate change effects on this group of reptiles.


Assuntos
Mudança Climática , Répteis/fisiologia , Aclimatação , Distribuição Animal , Animais , Biodiversidade , Temperatura Corporal
12.
J Therm Biol ; 73: 50-60, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29549991

RESUMO

Temperature increases can impact biodiversity and predicting their effects is one of the main challenges facing global climate-change research. Ectotherms are sensitive to temperature change and, although predictions indicate that tropical species are highly vulnerable to global warming, they remain one of the least studied groups with respect to the extent of physiological variation and local extinction risks. We model the extinction risks for a tropical heliothermic teiid lizard (Kentropyx calcarata) integrating previously obtained information on intraspecific phylogeographic structure, eco-physiological traits and contemporary species distributions in the Amazon rainforest and its ecotone to the Cerrado savannah. We also investigated how thermal-biology traits vary throughout the species' geographic range and the consequences of such variation for lineage vulnerability. We show substantial variation in thermal tolerance of individuals among thermally distinct sites. Thermal critical limits were highly correlated with operative environmental temperatures. Our physiological/climatic model predicted relative extinction risks for local populations within clades of K. calcarata for 2050 ranging between 26.1% and 70.8%, while for 2070, extinction risks ranged from 52.8% to 92.8%. Our results support the hypothesis that tropical-lizard taxa are at high risk of local extinction caused by increasing temperatures. However, the thermo-physiological differences found across the species' distribution suggest that local adaptation may allow persistence of this tropical ectotherm in global warming scenarios. These results will serve as basis to further research to investigate the strength of local adaptation to climate change. Persistence of Kentropyx calcarata also depends on forest preservation, but the Amazon rainforest is currently under high deforestation rates. We argue that higher conservation priority is necessary so the Amazon rainforest can fulfill its capacity to absorb the impacts of temperature increase on tropical ectotherms during climate change.


Assuntos
Aclimatação , Temperatura Corporal , Extinção Biológica , Aquecimento Global , Lagartos/fisiologia , Animais , Feminino , Locomoção , Masculino , Modelos Biológicos , Floresta Úmida , Fatores de Risco , Temperatura , Clima Tropical
13.
An Acad Bras Cienc ; 94(suppl 3): e20220450, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36477244
14.
PeerJ ; 12: e16986, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38685936

RESUMO

Environmental heterogeneity poses a significant influence on the functional characteristics of species and communities at local scales. Environmental transition zones, such as at the savanna-forest borders, can act as regions of ecological tension when subjected to sharp variations in the microclimate. For ectothermic organisms, such as lizards, environmental temperatures directly influence physiological capabilities, and some species use different thermoregulation strategies that produce varied responses to local climatic conditions, which in turn affect species occurrence and community dynamics. In the context of global warming, these various strategies confer different types of vulnerability as well as risks of extinction. To assess the vulnerability of a species and understand the relationships between environmental variations, thermal tolerance of a species and community structure, lizard communities in forest-savanna transition areas of two national parks in the southwestern Amazon were sampled and their thermal functional traits were characterized. Then, we investigated how community structure and functional thermal variation were shaped by two environmental predictors (i.e., microclimates estimated locally and vegetation structure estimated from remote sensing). It was found that the community structure was more strongly predicted by the canopy surface reflectance values obtained via remote sensing than by microclimate variables. Environmental temperatures were not the most important factor affecting the occurrence of species, and the variations in ecothermal traits demonstrated a pattern within the taxonomic hierarchy at the family level. This pattern may indicate a tendency for evolutionary history to indirectly influence these functional features. Considering the estimates of the thermal tolerance range and warming tolerance, thermoconformer lizards are likely to be more vulnerable and at greater risk of extinction due to global warming than thermoregulators. The latter, more associated with open environments, seem to take advantage of their lower vulnerability and occur in both habitat types across the transition, potentially out-competing and further increasing the risk of extinction and vulnerability of forest-adapted thermoconformer lizards in these transitional areas.


Assuntos
Lagartos , Microclima , Floresta Úmida , Animais , Lagartos/fisiologia , Pradaria , Brasil , Aquecimento Global
15.
PeerJ ; 11: e15186, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065686

RESUMO

Male researchers dominate scientific production in science, technology, engineering, and mathematics (STEM). However, potential mechanisms to avoid this gender imbalance remain poorly explored in STEM, including ecology and evolution areas. In the last decades, changes in the peer-review process towards double-anonymized (DA) have increased among ecology and evolution (EcoEvo) journals. Using comprehensive data on articles from 18 selected EcoEvo journals with an impact factor >1, we tested the effect of the DA peer-review process in female-leading (i.e., first and senior authors) articles. We tested whether the representation of female-leading authors differs between double and single-anonymized (SA) peer-reviewed journals. Also, we tested if the adoption of the DA by previous SA journals has increased the representativeness of female-leading authors over time. We found that publications led by female authors did not differ between DA and SA journals. Moreover, female-leading articles did not increase after changes from SA to DA peer-review. Tackling female underrepresentation in science is a complex task requiring many interventions. Still, our results highlight that adopting the DA peer-review system alone could be insufficient in fostering gender equality in EcoEvo scientific publications. Ecologists and evolutionists understand how diversity is important to ecosystems' resilience in facing environmental changes. The question remaining is: why is it so difficult to promote and keep this "diversity" in addition to equity and inclusion in the academic environment? We thus argue that all scientists, mentors, and research centers must be engaged in promoting solutions to gender bias by fostering diversity, inclusion, and affirmative measures.


Assuntos
Ecossistema , Sexismo , Humanos , Masculino , Feminino , Autoria , Ecologia , Publicações
16.
PeerJ ; 10: e14276, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312759

RESUMO

Background: Terrestrial biomes in South America are likely to experience a persistent increase in environmental temperature, possibly combined with moisture reduction due to climate change. In addition, natural fire ignition sources, such as lightning, can become more frequent under climate change scenarios since favourable environmental conditions are likely to occur more often. In this sense, changes in the frequency and magnitude of natural fires can impose novel stressors on different ecosystems according to their adaptation to fires. By focusing on Brazilian biomes, we use an innovative combination of techniques to quantify fire persistence and occurrence patterns over time and evaluate climate risk by considering key fire-related climatic characteristics. Then, we tested four major hypotheses considering the overall characteristics of fire-dependent, fire-independent, and fire-sensitive biomes concerning (1) fire persistence over time; (2) the relationship between climate and fire occurrence; (3) future predictions of climate change and its potential impacts on fire occurrence; and (4) climate risk faced by biomes. Methods: We performed a Detrended Fluctuation Analysis to test whether fires in Brazilian biomes are persistent over time. We considered four bioclimatic variables whose links to fire frequency and intensity are well-established to assess the relationship between climate and fire occurrence by confronting these climate predictors with a fire occurrence dataset through correlative models. To assess climate risk, we calculated the climate hazard, sensitivity, resilience, and vulnerability of Brazilian biomes, and then we multiplied the Biomes' vulnerability index by the hazards. Results: Our results indicate a persistent behaviour of fires in all Brazilian biomes at almost the same rates, which could represent human-induced patterns of fire persistence. We also corroborated our second hypothesis by showing that most fire-dependent biomes presented high thermal suitability to fire, while the fire-independent biome presented intermediate suitability and fire-sensitive biomes are the least suitable for fire occurrence. The third hypothesis was partially corroborated since fire-dependent and independent biomes are likely to increase their thermal suitability to fire, while fire-sensitive biomes are likely to present stable-to-decreasing thermal suitability in the future. Finally, our fourth hypothesis was partially corroborated since most fire-dependent biomes presented low climate risk, while the fire-independent biome presented a high risk and the fire-sensitive biomes presented opposite trends. In summary, while the patterns of fire persistence and fire occurrence over time are more likely to be related to human-induced fires, key drivers of burned areas are likely to be intensified across Brazilian biomes in the future, potentially increasing the magnitude of the fires and harming the biomes' integrity.


Assuntos
Ecossistema , Humanos , Brasil/epidemiologia , Temperatura , Fatores de Tempo
17.
J Exp Zool A Ecol Integr Physiol ; 335(1): 13-44, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32638552

RESUMO

Research on the thermal ecology and physiology of free-living organisms is accelerating as scientists and managers recognize the urgency of the global biodiversity crisis brought on by climate change. As ectotherms, temperature fundamentally affects most aspects of the lives of amphibians and reptiles, making them excellent models for studying how animals are impacted by changing temperatures. As research on this group of organisms accelerates, it is essential to maintain consistent and optimal methodology so that results can be compared across groups and over time. This review addresses the utility of reptiles and amphibians as model organisms for thermal studies by reviewing the best practices for research on their thermal ecology and physiology, and by highlighting key studies that have advanced the field with new and improved methods. We end by presenting several areas where reptiles and amphibians show great promise for further advancing our understanding of how temperature relations between organisms and their environments are impacted by global climate change.


Assuntos
Anfíbios/fisiologia , Temperatura Corporal/fisiologia , Ecossistema , Répteis/fisiologia , Anfíbios/embriologia , Anfíbios/crescimento & desenvolvimento , Animais , Embrião não Mamífero/fisiologia , Monitorização Fisiológica , Répteis/embriologia , Répteis/crescimento & desenvolvimento
19.
PLoS One ; 13(3): e0192834, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29513695

RESUMO

We summarize thermal-biology data of 69 species of Amazonian lizards, including mode of thermoregulation and field-active body temperatures (Tb). We also provide new data on preferred temperatures (Tpref), voluntary and thermal-tolerance ranges, and thermal-performance curves (TPC's) for 27 species from nine sites in the Brazilian Amazonia. We tested for phylogenetic signal and pairwise correlations among thermal traits. We found that species generally categorized as thermoregulators have the highest mean values for all thermal traits, and broader ranges for Tb, critical thermal maximum (CTmax) and optimal (Topt) temperatures. Species generally categorized as thermoconformers have large ranges for Tpref, critical thermal minimum (CTmin), and minimum voluntary (VTmin) temperatures for performance. Despite these differences, our results show that all thermal characteristics overlap between both groups and suggest that Amazonian lizards do not fit into discrete thermoregulatory categories. The traits are all correlated, with the exceptions of (1) Topt, which does not correlate with CTmax, and (2) CTmin, and correlates only with Topt. Weak phylogenetic signals for Tb, Tpref and VTmin indicate that these characters may be shaped by local environmental conditions and influenced by phylogeny. We found that open-habitat species perform well under present environmental conditions, without experiencing detectable thermal stress from high environmental temperatures induced in lab experiments. For forest-dwelling lizards, we expect warming trends in Amazonia to induce thermal stress, as temperatures surpass the thermal tolerances for these species.


Assuntos
Aclimatação/fisiologia , Regulação da Temperatura Corporal/fisiologia , Temperatura Corporal/fisiologia , Lagartos/fisiologia , Temperatura , Animais , Brasil , Ecossistema , Geografia , Lagartos/classificação , Especificidade da Espécie
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