Behavioral Thermoregulation Research Articles

Thermoregulation of stingless bee colonies in boxes for rationale breeding in the Center-West of the state of Maranhão

Indigenous stingless bees of the subfamily Meliponinae are recognized as bees native to Brazil. They have an atrophied sting and are widely distributed throughout tropical regions, from Mexico to the south of Brazil on the American Continent. This study was carried out to evaluate the thermoregulatory behavior in colonies of stingless bees allocated in rational breeding boxes in the municipality of Grajaú, Central West region of the state of Maranhão. The project was developed at the IFMA Grajaú Campus, where two models of rational breeding boxes for stingless bees were made to evaluate which of the models has greater colonial development of two species of bees (Melipona fasciculata and Melipona flavolineata) when transferred from the native nests to the rational breeding boxes. To this end, digital thermometers were installed in stingless bee hives and thermo-hygrometers to monitor the maximum and minimum daily temperature for six months. Despite a wide variation in maximum and minimum external temperatures, the bees managed to maintain the temperature between 23.5º and 33.9ºC and the relative humidity between 39 and 64% inside the hives throughout the days, especially the hives in model 1. This was the most adapted prototype for rearing bees in this experiment, with good thermoregulation of stingless bee colonies throughout the day in both species over the study months.

Lipid-Mediated Mechanisms of Thermal Adaptation and Thermoregulatory Behavior in Animals.

Temperature affects a variety of cellular processes because the molecular motion of cellular constituents and the rate of biochemical reactions are sensitive to temperature changes. Thus, the adaptation to temperature is necessary to maintain cellular functions during temperature fluctuation, particularly in poikilothermic organisms. For a wide range of organisms, cellular lipid molecules play a pivotal role during thermal adaptation. Temperature changes affect the physicochemical properties of lipid molecules, resulting in the alteration of cell membrane-related functions and energy metabolism. Since the chemical structures of lipid molecules determine their physicochemical properties and cellular functions, cellular lipids, particularly fatty acid-containing lipid molecules, are remodeled as a thermal adaptation response to compensate for the effects of temperature change. In this chapter, we first introduce the structure and biosynthetic pathway of fatty acid-containing lipid molecules, such as phospholipid and triacylglycerol, followed by a description of the cellular lipid-mediated mechanisms of thermal adaptation and thermoregulatory behavior in animals.

Hydric physiology and ecology of a federally endangered desert lizard.

Animals can respond to extreme climates by behaviourally avoiding it or by physiologically coping with it. We understand behavioural and physiological thermoregulation, but water balance has largely been neglected. Climate change includes both global warming and changes in precipitation regimes, so improving our understanding of organismal water balance is increasingly urgent. We assessed the hydric physiology of US federally endangered blunt-nosed leopard lizards (Gambelia sila) by measuring cutaneous evaporative water loss (CEWL), plasma osmolality and body condition. Measurements were taken throughout their active season, the short period of year when these lizards can be found aboveground. Compared to a more mesic species, G. sila had low CEWL which is potentially desert-adaptive, and high plasma osmolality that could be indicative of dehydration. We hypothesized that throughout the G. sila active season, as their habitat got hotter and drier, G. sila would become more dehydrated and watertight. Instead, CEWL and plasma osmolality showed minimal change for females and non-linear change for males, which we hypothesize is connected to sex-specific reproductive behaviours and changes in food availability. We also measured thermoregulation and microhabitat use, expecting that more dehydrated lizards would have lower body temperature, poorer thermoregulatory accuracy and spend less time aboveground. However, we found no effect of CEWL, plasma osmolality or body condition on these thermal and behavioural metrics. Finally, G. sila spends considerable time belowground in burrows, and burrows may serve not only as essential thermal refugia but also hydric refugia.

Некоторые черты термобиологии разноцветной ящурки Eremias arguta (Gmelin, 1789) и круглоголовки-вертихвостки Phrynocephalus guttatus (Gmelin, 1789) (Squamata, Reptilia) при совместном обитании в Северном Прикаспии

The paper presents data on temperatures of the body and the selected substrate for the steppe-runner and the spotted toadhead agama. Thermal preferences and modal classes for both species were determined, and interspecies differences were analyzed. Significantly higher average temperatures were found in the steppe-runner, while the maximum voluntary temperatures are higher in the spotted toadhead agama. These features are associated with the biotopic confinement of species. Representatives of both species, even in the spring, have a lower body temperature compared to the environment, which is achieved due to behavioral thermoregulation.

Octopamine is involved in TRP-induced thermopreference responses in American cockroach

Insects’ thermoregulatory processes depend on thermosensation and further processing of thermal information in the nervous system. It is commonly known that thermosensation involves thermoreceptors, including members of the TRP receptor family, but the involvement of neurotransmitters in thermoregulatory pathways remains unstudied. We conducted test to determine whether octopamine, a biogenic amine that acts as a neurotransmitter and neurohormone in insects, is involved in TRP-induced thermoregulatory responses in Periplaneta americana. We used capsaicin, an activator of the heat-sensitive TRP channel, Painless, to induce thermoregulatory response in cockroaches. Then, we evaluated the behavioural (thermal preferences and grooming), physiological (heart rate) and biochemical responses of insects to capsaicin, octopamine and phentolamine – octopaminergic receptor blocker. Capsaicin, similar to octopamine, increased cockroaches’ grooming activity and heart rate. Moreover, octopamine level and protein kinase A (PKA) activity significantly increased after capsaicin treatment. Blocking octopaminergic receptors with phentolamine diminished cockroaches’ response to capsaicin – thermoregulatory behaviour, grooming and heart rate were abolished. The results indicate that octopamine is a neurotransmitter secreted in insects after the activation of heat receptors.

Study of Fever Presentation in DAE Hospital

Introduction Background-Although earliest fever curves was created in 10th century by Akhawayni, fever was reported by Beeson (1961) as the presence of an endogenous pyrogen in rabbit PMNL. Today the granulocyte factor is the central role in pathogenesis of fever. Normal body temp is 98.6*f and fever is a complex physiological response involving the innate immune system and any temperature beyond the normal. Hippocrates and Kos (377BCE) attributed to pyretos and therme (fever and heat) which arose from 4 elements-blood, phlegm, black bile and yellow bile. Farenheit and Celsius were pioneers in development of thermometer and axillary temperatures were first used for fever Then Mackowiak and collegues described an oral thermometer and they gave 98.6*f as normal and 99.9*f as upper limit of normal. Thermoregulatory behaviours (brown adipose tissue thermogenesis, shivering, sweating, vasoconstriction and vasodilation) are the control loops in response to core and skin temperature. Of the illnesses, infection, neoplasia, inflammatory, miscellaneous and undiagnosed illness form the main group. In India, infections constitute 16-55% of cases. Now in industrialized countries, undiagnosed cases have risen. Among the infections, UTI, TB, viral and protozoal abcess, endocarditis are frequently diagnosed out of which viral infections predominate. In older patients infections are less frequent cause of fever which is opposite to pediatric population. Travel history and vaccination history is important as in COVID era. Lab findings were consistant with clinical presentation in 90% of cases .Mortality out of fever was very negligible only in older patients (1-3%).

EFFECTS OF SEASON, SEX AND TIME OF DAY ON OSTRICH BREEDER (Struthio camelus) BEHAVIOR

Ambient temperature has a crucial effect on livestock production performance, behaviors and welfare. In ostrich, previous research primarily focused on survival and reproductive performance during the climatic shifts. This study was carried out to investigate the effect of seasonal variation on behavioral differences of male and female ostrich (Struthio camelus) breeders, reared in farm environment. The individual behaviors related to digestion, locomotor activities, resting, comfort and thermoregulation, reproduction, and aggressive behaviors were recorded. The higher sitting and sleeping behavior were observed in summer season (P≤0.01 and P≤0.001, respectively). The thermoregulation behaviors were observed only in summer season (P≤0.0001). The higher foraging, alertness and spot pecking behaviors were observed in females (P≤0.01, P≤0.05, and P≤0.05, respectively). The boom behavior was only observed in males (P≤0.05). The higher walking behavior was observed in the afternoon and morning (P≤0.05). The higher sleeping, dust bathing, grooming and thermoregulation behaviors were observed at noon (P≤0.001, P≤0.001, P≤0.0001 and P≤0.0001, respectively). There was a significant interaction between season and sex for displace behavior, a sign of aggressive behavior (P=0.006). There was a significant interaction between season and time of day for drinking and defecation related to digestive behaviors (P≤0.05 and P≤0.05, respectively); sleeping described as a resting behavior (P=0.0001); dust bathing and grooming which is related to comfort behaviors (P≤0.0001 and P≤0.0001); thermoregulation (P≤0.0001); copulation described as a reproductive behavior (P=0.003); displace and escape behaviors mostly a sign of aggressive behavior (P≤0.05 and P≤0.05). Ostriches are diurnal animals with a nomadic lifestyle and have higher activity during the early and late times of the day. Identification of the seasonal, sexual and time of day differences on behavior types of ostriches, provides important information for ostrich management and their welfare. Keywords: Ostrich (Struthio camelus), climate-change, behavior, animal welfare.

The impacts of global warming on animals and their response to climate warming

This paper reviews on animals’ thermoregulations under climate change. There are aspects of animals’ thermoregulation that encompass behavior, physiology, and life history. Among these, behavioral thermoregulation is mostly studied and reported in the early years, which is usually about the strategic selection of optimal timing and locations, facilitating efficient evaporative and conduction heat dissipation, modifying their dietary preferences, and increasing shuttle behavior. The field of physiology involves hormonal regulation, such as secreting more glucocorticoids to achieve better balance control, changing body temperature to be more efficient in heat loss, energy allocation (e.g., metabolic rate) to select optimal strategy between growth and reproduction, and oxidative stress injury. In parallel, life history traits encompass rising growth rate, shrinking lifespan, changing body posture, and declining survival rate. Global warming is the main feature of climate change, with both of the average temperature rising and frequently heat waves occurring being the major characteristics simultaneously. Consequently, there come two scientific questions of this review: (1) What are the impacts of global warming on animals?(2) How do animals respond to climate change?

A rockling's choice: The trade-off between thermal preference and physical structure in the five bearded rockling, Ciliata mustela

Changes in the environment can alter the suitability of habitats for organisms. In marine systems, fish species have their own specific requirements in terms of temperature and other habitat features. Behavioral responses such as thermoregulatory behavior in ectothermic species allow mobile organisms to respond to detrimental changes and search for more suitable habitats. However, for many species, limited information exists on the ecological requirements to help explain species abundance in a changing habitat. An example of a quickly changing habitat is the Wadden Sea, where five bearded rockling (Ciliata mustela) abundance has increased, unlike other Wadden Sea species. The increasing abundance of rockling has coincided with increasing average sea water temperatures and the recovery of mussel and Pacific oyster beds. Warming waters and increased structural habitat may have provided rockling with a more desirable habitat. Therefore, to better understand why rockling abundance is increasing within a changing Wadden Sea, a water temperature preference chamber was used to determine rockling's preferred temperature range. In addition, rockling's affinity for structural habitat and the trade-off between preferred temperature was examined by following their response to the systematic removal of artificial physical structures within the preferred temperature conditions. The preferred temperature range of rockling was found to be 10.4–15.7 °C. Following structure removals, rockling repeatedly moved away from their chosen temperatures to adjacent compartments with different temperatures but containing physical structure, indicating that the presence of physical structure was more important than preferred temperature until 18.6 °C. These novel findings provide insight and experimental support for the hypothesis explaining rockling's increase in the Wadden Sea: 1) mean annual temperatures have been steadily increasing towards rockling's preferred thermal range and 2) increasing mussel and Pacific oyster beds are plausibly providing structural habitat, an important habitat requirement for rockling. When fish display a strong association with physical structure it is necessary to link physiological and habitat preferences to better understand climate change related responses.

Small increases in ambient temperature reduce offspring body mass in an equatorial mammal.

Human-induced climate change is leading to temperature rises, along with increases in the frequency and intensity of heatwaves. Many animals respond to high temperatures through behavioural thermoregulation, for example by resting in the shade, but this may impose opportunity costs by reducing foraging time (therefore energy supply), and so may be most effective when food is abundant. However, the heat dissipation limit (HDL) theory proposes that even when energy supply is plentiful, high temperatures can still have negative effects. This is because dissipating excess heat becomes harder, which limits processes that generate heat such as lactation. We tested predictions from HDL on a wild, equatorial population of banded mongooses (Mungos mungo). In support of the HDL theory, higher ambient temperatures led to lighter pups, and increasing food availability made little difference to pup weight under hotter conditions. This suggests that direct physiological constraints rather than opportunity costs of behavioural thermoregulation explain the negative impact of high temperatures on pup growth. Our results indicate that climate change may be particularly important for equatorial species, which often experience high temperatures year-round so cannot time reproduction to coincide with cooler conditions.

Parental exposure to heat waves improves offspring reproductive investment in Tetranychus urticae (Acari: Tetranychidae), but not in its predator, Phytoseiulus persimilis (Acari: Phytoseiidae).

The more frequent and intense occurrence of heat waves is a challenge for arthropods because their unpredictable incidence requires fast adaptations by the exposed individuals. Phenotypic plasticity within and across generations might be a solution to cope with the detrimental effects of heat waves, especially for fast-developing, small arthropods with limited dispersal abilities. Therefore, we studied whether severe heat may affect the reproduction of a pest species, the spider mite Tetranychus urticae, and its counterpart, the predatory mite Phytoseiulus persimilis. Single offspring females with different parental thermal origins (reared under mild or extreme heat waves) of both species were exposed to mild or extreme heat waves on bean leaves over 10 days, and the oviposition, egg sizes, survival, and escape behavior of the females were evaluated daily. The total losses of predators mainly via escapers were very high compared to prey, which makes a separation between selective and plastic effects on shifted reproductive traits impossible. Predator females laid smaller eggs, while their consumption and oviposition rates were unaffected during extreme heat waves. In comparison, larger prey females fed more and produced more, but smaller, eggs due to within- and trans-generational effects. These advantages for the prey in comparison to its predator when exposed to extreme heat waves during the reproductive phase support the trophic sensitivity hypothesis: higher trophic levels (i.e., the predator) are more sensitive to thermal stress than lower trophic levels (i.e., the prey). Furthermore, the species-specific responses may reflect their lifestyles. The proactive and mobile predator should be selected for behavioral thermoregulation under heat waves via spatiotemporal avoidance of heat-exposed locations rather than relying on physiological adaptations in contrast to the more sessile prey. Whether these findings also influence predator-prey interactions and their population dynamics under heat waves remains an open question.

Dehydration alters behavioral thermoregulation and the geography of climatic vulnerability in two Amazonian lizards.

High temperatures and low water availability often strike organisms concomitantly. Observing how organisms behaviorally thermohydroregulate may help us to better understand their climatic vulnerability. This is especially important for tropical forest lizards, species that are purportedly under greater climatic risk. Here, we observed the influence of hydration level on the Voluntary Thermal Maximum (VTmax) in two small Amazonian lizard species: Loxopholis ferreirai (semiaquatic and scansorial) and Loxopholis percarinatum (leaf litter parthenogenetic dweller), accounting for several potential confounding factors (handling, body mass, starting temperature and heating rate). Next, we used two modeling approaches (simple mapping of thermal margins and NicheMapR) to compare the effects of dehydration, decrease in precipitation, ability to burrow, and tree cover availability, on geographic models of climatic vulnerability. We found that VTmax decreased with dehydration, starting temperature, and heating rates in both species. The two modeling approaches showed that dehydration may alter the expected intensity, extent, and duration of perceived thermal risk across the Amazon basin for these forest lizards. Based on our results and previous studies, we identify new evidence needed to better understand thermohydroregulation and to model the geography of climatic risk using the VTmax.

Flexible simulation of animal thermoregulatory behavior in three-dimensional synthetic environments from thermal and optical images

Several animals have low metabolism and show body temperatures that are in accordance with environmental temperatures. The relationship between environmental temperature and body temperature is influenced by body size and behavior, in which that some animals accept thermal variation whereas others regulate temperature through behavior. Three-dimensional (3D) environments based on thermal imaging represent a solid tool to elucidate this thermoregulatory behavior to help understand important topics in thermal ecology such as estimating cost of thermoregulation under realistic field conditions, as well as compute the risk of overheating and thermal damage under different ecological scenarios. Although in some studies the proposed models simulate thermoregulation, the connection between thermal and optical image is not explored. This junction can offer a more useful 3D visualization, where topological structures of the landscape can be observed together with thermal information. In this article we present a computational system that is not only capable of generating 3D models by using both thermal and optical images, but is also capable of simulating the thermoregulation behaviors of several animals by means of parameter adjustments made by the user. Our system was analyzed by 22 experts in the biology area – most of them with teaching experience –, who answered objective questions based on their knowledge about the topic, as well as questions about their perception on the simulation provided by our proposal. We used a technology acceptance questionnaire and asked for their contributions through their suggestions. The objective questions reached a hit rate of 68%, which suggests that is relatively easy to use the environment, providing clear comprehension about the simulation, although there is the possibility for improvements. We also found that the hit rate is not related to the experts' level of experience nor with the volunteers' familiarity with 3D environments. Also, 95% of the volunteers indicate a high degree of perceived usefulness, suggesting a potential for using our proposal in teaching and research activities.

Head Regional Differences in Thermal Comfort: Evaluating a Novel Surgical Helmet Cooling Method with Phase Change Material

Thermal comfort is a significant factor in maintaining a satisfactory perception of the body temperature and influences behavioral thermoregulation. This pilot study aimed to investigate regional differences in thermal comfort in the head and neck areas by applying a surgical helmet equipped with cooling pads containing octadecane (CAS 593-45-3) as a phase change material (PCM) in healthy volunteers. Forty-three surgeons and nurses were enrolled. Octadecane is an odorless alkane hydrocarbon with an appearance of white crystal and a melting point of 28 °C. The PCM pads, each with a diameter of 5 cm and containing 7 g of octadecane, were placed between the helmet and the wearer’s head directly in contact with the skin. To identify the areas of the head and neck investigated, the surface was sampled and numbered, with the identification of a total of 38 different locations. A climate chamber maintained at 23–26 °C was used for the experiment. Thermal comfort of the stimulated area was reported by the subjects in an evaluation questionnaire at the end of the local stimulation conducted for 1 h. The sensations were reported as 1 (maximum uncomfortable) to 7 (maximum cold comfort), with 4 indicating a neutral sensation. The duration of the thermal comfort effect was also recorded. The highest mean value reported was 6 in five areas. The frontal region, the frontotemporal region, and the neck region were the areas sensitive to thermal comfort. A neutral sensation was reported in 13 areas. No uncomfortable sensation was reported in any area. This pilot study provides preliminary evidence of the feasibility and potential benefits of integrating PCM cooling pads into surgical helmets to enhance thermal comfort.

Similarities and differences regarding acute anorexia nervosa and semi-starvation: does behavioral thermoregulation play a central role?

To clarify the association between acute anorexia nervosa (AN) and semi-starvation (SS) by focusing on similarities and differences in physiology, mood, and behavior. A comparison of published literature between these two groups. Both groups show similar hormonal and metabolic changes in response to caloric restriction and extreme weight loss (~25%). Associated changes result in a reduced body temperature (Tcore-low). Maintenance of body temperature within a specific range is crucial to survival. However, both groups cannot activate autonomic strategies to maintain their Tcore-low, such as increasing metabolic rate, constricting skin blood vessels, or shivering. Furthermore, Tcore-low increases the individuals' "coldness sensations" throughout the body, hence the frequent reports from ANs and SSs of "feeling cold." To eliminate these uncomfortable "coldness sensations" and, importantly, to maintain Tcore-low, ANs, and SSs "select" different thermoregulatory behavioral strategies. It is proposed that the primary differences between AN and SS, based on genetics, now manifest due to the "selection" of different thermo-regulatory behaviors. AN patients (ANs) "select" hyperactive behavior (HyAc), which increases internal metabolic heat and thus assists with maintaining Tcore-low; in harmony with hyperactive behavior is a lively mood. Also related to this elevated arousal pattern, ANs experience disrupted sleep. In contrast, SS individuals "select" a passive thermo-behavioral strategy, "shallow torpor," which includes reduced activity, resulting in energy conservation. In addition, this inactivity aids in the retention of generated metabolic heat. Corresponding to this lethargic behavior, SS individuals display a listless mood and increased sleep. Initial similarities between the two are attributable to physiological changes related to extreme weight loss. Differences are most likely attributable to genetically programmed "selection" of alternate thermoregulatory strategies, primarily to maintain Tcore-low. However, if acute AN is prolonged and evolves into a chronic condition, AN will more closely align with starvation and more precisely reflect SS symptomology.

Seasonal Variation in the Thermoregulation Pattern of an Insular Agamid Lizard.

Ectotherms, including lizards, rely on behavioral thermoregulation to maintain their body temperature within an optimal range. The benign climate of islands is expected to favor the thermoregulation efficiency of reptiles throughout their activity period. In this study, we investigated the seasonal variation in thermoregulation in an insular population of the roughtail rock agama (Laudakia stellio) on Naxos Island, Greece. We measured body, operative, and preferred temperatures across three seasons (spring, summer, and autumn), and we evaluated the effectiveness of thermoregulation, using the Hertz index (E). Our results revealed that the effectiveness of thermoregulation was significantly influenced by seasonality. E was quite high in summer (0.97) and spring (0.92), and lowest in autumn (0.81). Accordingly, the quality of the thermal environment was significantly low during autumn, and maximum during summer. However, despite the environmental temperature fluctuations, lizards exhibited remarkable stability in body temperatures. They also adjusted their preferred temperatures seasonally and doubled the thermal niche breadth they occupied during summer, thus enhancing thermoregulation efficiency. Whether or not these adjustments are plastic or fixed local adaptations remains to be explored in further research across multiple years and seasons, including additional insular populations.

Chemogenetic Modulation of Posterior Insula CaMKIIa Neurons Alters Pain and Thermoregulation

The posterior insular cortex (PIC) is well positioned to perform somatosensory-limbic integration; yet, the function of neuronal subsets within the PIC in processing the sensory and affective dimensions of pain remains unclear. Here, we employ bidirectional chemogenetic modulation to characterize the function of PIC CaMKIIa-expressing excitatory neurons in a comprehensive array of sensory, affective, and thermoregulatory behaviors. Excitatory pyramidal neurons in the PIC were found to be sensitized under inflammatory pain conditions. Chemogenetic activation of excitatory CaMKIIa-expressing PIC neurons in non-injured conditions produced an increase in reflexive and affective pain- and anxiety-like behaviors. Moreover, activation of PIC CaMKIIa-expressing neurons during inflammatory pain conditions exacerbated hyperalgesia and decreased pain tolerance. However, Chemogenetic activation did not alter heat nociception via hot plate latency or body temperature. Conversely, inhibiting CaMKIIa-expressing neurons did not alter either sensory or affective pain-like behaviors in non-injured or under inflammatory pain conditions, but it did decrease body temperature and decreased hot plate latency. Our findings reveal that PIC CaMKIIa-expressing neurons are a critical hub for producing both sensory and affective pain-like behaviors and important for thermoregulatory processing. PerspectiveThe present study reveals that activation of the posterior insula produces hyperalgesia and negative affect, and has a role in thermal tolerance and thermoregulation. These findings highlight the insula as a key player in contributing to the multidimensionality of pain.

Compensation for exposure to increased environmental temperatures is costly in a montane, desert lizard

Extreme weather events will increase in frequency and intensity with climate change. Physiological and behavioral modulation during these extreme climatic events will likely facilitate persistence of ectothermic species, but these compensatory responses may be costly. We transplanted greater short-horned lizards (Phrynosoma hernandesi) from a cool, high-elevation site to a warm, low-elevation site to quantify the costs of acute temperature increases. We predicted that transplanting lizards to the warmer environment would increase mass loss relative to Control lizards by increasing DEE, thermal tolerance, and circulating CORT and altering spatial ecology and basking behavior. We found that transplanted lizards experienced a significant decline in mass, but this decline was not a result of increased energetic expenditure or circulating CORT. Rather, this loss appeared to be driven by changes in basking behavior and space use. Our data suggest changes in thermoregulatory behavior alleviated the direct effects of a greater environmental thermal load. However, these behavioral changes were associated with their own costs, likely due to limitations on resource acquisition resulting from decreases in basking and foraging activities. Our research suggests compensation for increased temperatures does not necessarily eliminate the costs of rapid environmental change.

A predominantly diurnal tropical mammal increases nocturnality in response to high temperatures

AbstractThe extent to which animals may compensate for rising temperatures through behavioral thermoregulation is an important unknown in predicting responses to climate change. Flexibility in temporal activity in particular may be an important factor in determining species' vulnerability. In this study, we examine whether the white‐lipped peccary, a predominantly diurnal Neotropical mammal, shifts its temporal activity and microclimate selection in response to daily temperature variation in the Pantanal biome of Brazil. From November 2021 to October 2022, we deployed camera traps and microclimate data loggers to record white‐lipped peccary activity and air temperature on a fine spatiotemporal scale. We found that the percentage of peccary activity that is nocturnal increased with maximum daily temperature at a rate of 3.7% per 1°C past a threshold of 31.2°C, and increased with maximum daily wet‐bulb temperature at a rate of 4.7% per 1°C past a threshold of 24.9°C. The afternoon period (i.e., solar noon to sunset) went from having the highest frequency of peccary activity at the lower end of our observed temperature range to having the lowest frequency of activity at the higher end. We did not find evidence of microclimate selection. Our findings indicate that white‐lipped peccaries in the Pantanal demonstrate substantial behavioral flexibility in their response to high temperatures, which may help to buffer them against the impact of rising temperatures caused by climate change.Abstract in Portuguese is available with online material.

Oxygen Availability Affects Behavioural Thermoregulation of Turtle Embryos

Oxygen Availability Affects Behavioural Thermoregulation of Turtle Embryos