This document summarizes a study on the thermal ecology of the European tree frog (Hyla arborea) in western France. The study measured body temperatures of 108 frogs over six years during sunny and overcast weather conditions. Body temperatures were higher on sunny days but showed similar variability. Body temperatures correlated most closely with temperatures of shaded leaves, regardless of weather. This suggests H. arborea controls its body temperature through selecting shaded microhabitats, though some frogs were observed basking in sunny areas, even on hot days.
This study examines the thermal ecology of Ceratophora tennentii, an endangered agamid lizard found only in Sri Lanka's Knuckles Massif cloud forests. Over 165 lizards were observed and their body temperatures measured, along with associated air and substrate temperatures. The results showed that C. tennentii operates at relatively low body temperatures that closely track air temperatures, maintaining on average only 0.8°C above air temperature. This suggests the lizards partially abandon active thermoregulation in favor of thermoconformity due to the thermal challenges of their cloud forest habitat. The study provides novel insights into the thermal biology of this rare species and recommendations for further research needed to aid conservation efforts
This document summarizes a study on the thermoregulatory behavior of the lizard Calotes versicolor at two different altitudes in Sri Lanka. Operative temperatures and lizard body temperatures were measured at a low altitude of 91 meters and high altitude of over 900 meters. The study found that lizards at the high altitude had to increase basking behavior to raise their body temperature due to cooler temperatures, while lizards at the low altitude engaged in more shade seeking to avoid high temperatures. Precision of body temperatures was not significantly different between the two populations. The document also presents preliminary models of how altitude generally influences body temperatures in Calotes lizards and other reptiles in the region.
This study examined the body temperatures of common toads (Bufo bufo) in France. The main findings were:
1) Nocturnal body temperatures ranged from 11.7-18.9°C and were associated with air and substrate temperatures.
2) Diurnal body temperatures ranged from 27.8-34.2°C and were significantly lower than open substrate temperatures but not shaded air temperatures.
3) Toad activity and body temperatures occurred over a similar period to other studies, from March to November, defining their thermal niche for the year.
60; body temperatures and retreat site selection in saurodactylusRoger Meek
- Observations were made of the ground-dwelling lizard Saurodactylus brosseti in southern Morocco to study its retreat site characteristics and body temperatures. The study found that lizards selected retreat sites under significantly larger rocks than randomly selected rocks. Diurnal substrate temperatures inside retreat sites closely matched lizard body temperatures, though both decreased when sea mists were present and increased as conditions warmed. A regression analysis indicated the lizards exhibited partial thermoregulation. Relative humidity under retreat site rocks was significantly higher than outside humidity, suggesting lizards select sites that avoid extreme temperatures and low humidity.
investigating the genetic basis of adapationPhilippe Henry
This document summarizes research investigating the genetic basis of adaptation in American pikas to climate change. Key findings include:
1) There was no evidence that pikas are migrating upslope to track warming temperatures, suggesting upslope migration is not a viable strategy for coping with climate change.
2) Genomic scans identified 20 loci under selection across elevation gradients that may confer adaptation to changing climate variables like precipitation and temperature.
3) Precipitation and maximum summer temperature were identified as potential selective forces shaping adaptation at these loci.
The document provides a high-level summary of a report on mountains in three sentences or less. It begins by classifying the mountains as one of the greatest systems in the world. It then explains why they are considered one of the greatest, using precise, descriptive language presented in the present tense. The report is organized logically to be easy to follow, with some paragraphs having implicit subtitles like "climate" to structure the information.
Andy Lowe_Space as a proxy for time: the Australian Transect NetworkTERN Australia
The Australian Transect Network establishes long-term monitoring sites along environmental gradients across Australia to track changes in species composition, traits, and genes over time and space in response to climate change, using space as a proxy for time. Data from the transects are used to validate models, engage citizens in science, and inform policy decisions about landscape management and climate adaptation. The network includes transects in northern, southwestern, and southeastern Australia that monitor vegetation and wildlife along climatic and disturbance gradients.
Habitat Model of Himanthalia elongata: responses to a warming climateBanco Español de Algas
This document summarizes a study on developing a habitat distribution model for the seaweed Himanthalia elongata in response to warming climate conditions. The study collected presence/absence data for H. elongata across 1,189 grid cells and selected 7 environmental predictors including sea surface temperature, air temperature, cloudiness, waves, and substrate type. Statistical analyses identified the most important predictors as mean August sea surface temperature, mean maximum August air temperature, and presence of rocky substrate. The results indicate H. elongata is currently present in colder sea and air conditions, suggesting its distribution may retract westward as temperatures rise with climate change.
This study examines the thermal ecology of Ceratophora tennentii, an endangered agamid lizard found only in Sri Lanka's Knuckles Massif cloud forests. Over 165 lizards were observed and their body temperatures measured, along with associated air and substrate temperatures. The results showed that C. tennentii operates at relatively low body temperatures that closely track air temperatures, maintaining on average only 0.8°C above air temperature. This suggests the lizards partially abandon active thermoregulation in favor of thermoconformity due to the thermal challenges of their cloud forest habitat. The study provides novel insights into the thermal biology of this rare species and recommendations for further research needed to aid conservation efforts
This document summarizes a study on the thermoregulatory behavior of the lizard Calotes versicolor at two different altitudes in Sri Lanka. Operative temperatures and lizard body temperatures were measured at a low altitude of 91 meters and high altitude of over 900 meters. The study found that lizards at the high altitude had to increase basking behavior to raise their body temperature due to cooler temperatures, while lizards at the low altitude engaged in more shade seeking to avoid high temperatures. Precision of body temperatures was not significantly different between the two populations. The document also presents preliminary models of how altitude generally influences body temperatures in Calotes lizards and other reptiles in the region.
This study examined the body temperatures of common toads (Bufo bufo) in France. The main findings were:
1) Nocturnal body temperatures ranged from 11.7-18.9°C and were associated with air and substrate temperatures.
2) Diurnal body temperatures ranged from 27.8-34.2°C and were significantly lower than open substrate temperatures but not shaded air temperatures.
3) Toad activity and body temperatures occurred over a similar period to other studies, from March to November, defining their thermal niche for the year.
60; body temperatures and retreat site selection in saurodactylusRoger Meek
- Observations were made of the ground-dwelling lizard Saurodactylus brosseti in southern Morocco to study its retreat site characteristics and body temperatures. The study found that lizards selected retreat sites under significantly larger rocks than randomly selected rocks. Diurnal substrate temperatures inside retreat sites closely matched lizard body temperatures, though both decreased when sea mists were present and increased as conditions warmed. A regression analysis indicated the lizards exhibited partial thermoregulation. Relative humidity under retreat site rocks was significantly higher than outside humidity, suggesting lizards select sites that avoid extreme temperatures and low humidity.
investigating the genetic basis of adapationPhilippe Henry
This document summarizes research investigating the genetic basis of adaptation in American pikas to climate change. Key findings include:
1) There was no evidence that pikas are migrating upslope to track warming temperatures, suggesting upslope migration is not a viable strategy for coping with climate change.
2) Genomic scans identified 20 loci under selection across elevation gradients that may confer adaptation to changing climate variables like precipitation and temperature.
3) Precipitation and maximum summer temperature were identified as potential selective forces shaping adaptation at these loci.
The document provides a high-level summary of a report on mountains in three sentences or less. It begins by classifying the mountains as one of the greatest systems in the world. It then explains why they are considered one of the greatest, using precise, descriptive language presented in the present tense. The report is organized logically to be easy to follow, with some paragraphs having implicit subtitles like "climate" to structure the information.
Andy Lowe_Space as a proxy for time: the Australian Transect NetworkTERN Australia
The Australian Transect Network establishes long-term monitoring sites along environmental gradients across Australia to track changes in species composition, traits, and genes over time and space in response to climate change, using space as a proxy for time. Data from the transects are used to validate models, engage citizens in science, and inform policy decisions about landscape management and climate adaptation. The network includes transects in northern, southwestern, and southeastern Australia that monitor vegetation and wildlife along climatic and disturbance gradients.
Habitat Model of Himanthalia elongata: responses to a warming climateBanco Español de Algas
This document summarizes a study on developing a habitat distribution model for the seaweed Himanthalia elongata in response to warming climate conditions. The study collected presence/absence data for H. elongata across 1,189 grid cells and selected 7 environmental predictors including sea surface temperature, air temperature, cloudiness, waves, and substrate type. Statistical analyses identified the most important predictors as mean August sea surface temperature, mean maximum August air temperature, and presence of rocky substrate. The results indicate H. elongata is currently present in colder sea and air conditions, suggesting its distribution may retract westward as temperatures rise with climate change.
This document describes a new platform called Arboreal that aims to connect people with project ideas to people with specific skills to collaborate on projects. It discusses features like creating groups for different projects and skills, bidding on project roles, and searching or getting recommendations to find project teammates. It also acknowledges competition from other platforms but notes Arboreal is targeting new projects not just established startups, and that the creators plan to take more design time up front to avoid needing a complete revamp later.
Primates inhabit various forest types across tropical and subtropical regions. Their ecological niches depend on requirements for resources and space. Abiotic factors like climate, water, and minerals affect primate habitats and behaviors, as do biotic factors such as availability of food sources and interactions with other animals including mates, group members, competitors, and predators. Conservation of primate populations faces threats from habitat destruction and hunting.
1) An ecological niche refers to the function a species carries out in its habitat through its use of resources and interactions with other community components.
2) If two species occupy the same exact ecological niche, competition will occur until one species dominates.
3) All species that live in the same habitat have some differences in their niches that allow them to avoid competition, even if aspects of their niches overlap.
Amphibians: What do we know about them?Gururaja KV
Amphibians are vertebrates that can live both on land and in water. They go through a metamorphosis from an aquatic tadpole stage to a terrestrial adult stage. Amphibians are important for ecosystems and human welfare. They indicate environmental changes and provide benefits like controlling pests, serving as traditional medicine, and acting as biological indicators. India is home to 309 amphibian species across 14 families and 55 genera. Ongoing research in India includes studies on reproduction, taxonomy, ecology, and impacts of skin extracts. Conservation efforts aim to protect amphibian habitats and diversity in the Western Ghats.
An ecosystem is defined as a habitat and all the living things within it. A habitat provides living things with food, water, shelter, and space. Most plants and animals in an ecosystem are specially adapted to the conditions of their particular habitat through adaptations like webbed feet, storage organs, or camouflage, which help them survive.
This document summarizes the concept of ecological niche. It discusses niche as a species' habitat requirements, its functional role in an ecosystem, and its position within a local community. Key concepts covered include the fundamental niche representing all conditions a species can persist in, versus the realized niche reflecting interactions with other species; competitive exclusion and limiting similarity regarding how similar niches can be for coexistence; and modes of coexistence such as niche differentiation and dominance hierarchies.
This document discusses human evolution and the timeline of early hominids. It begins by exploring basic questions about human origins and ancestry. It then examines the earliest hominid fossil sites in Africa dating back 6-7 million years, including Sahelanthropus tchadensis from Chad dated to nearly 7 million years old. While the evolutionary relationships between early hominids is still debated, most evidence suggests humans diverged from chimpanzees around 5-7 million years ago. Upright posture evolved in hominids before large brain size. Later sections explore the classification of primates and traits that distinguish hominids from other groups.
The document is a presentation from Miss Thomas' 4th grade class about different animal habitats including polar regions, coniferous forests, grasslands, deserts, tropical forests, oceans, and the animals that can survive in each habitat and how they do so. It includes images from WWF and Apple iPhoto to illustrate the different habitats.
Forests, wetlands, oceans, and deserts are common habitats that support different types of plants and animals. Forests provide habitat for deer and many other species among the trees and plants. Wetlands are covered with water and are home to animals like bullfrogs. Oceans contain salt water and various fish live in the ocean habitat. Deserts receive little rain, can be hot during the day, and certain animals have adapted to live in the dry desert environment.
Class IV - Adaptations-How Animals SurviveLearnRoots
The document discusses how animals have adapted to survive in different environments. It describes how animals are classified based on whether they have a backbone or not. It then covers the main groups of vertebrates - fish, amphibians, reptiles, birds, and mammals. For each group, it outlines key characteristics like how they breathe, their temperature regulation, and examples. It also discusses how animals have adapted to live in different habitats like land, water, trees, and air. Finally, it covers adaptations related to food sources, protection, and endangered species.
The document discusses where different types of animals live. Land animals live on earth, aquatic animals live in water, and air terrestrial animals fly in the sky. It lists land animals, aquatic animals, and air terrestrial animals.
The document discusses animal adaptations, defining them as body structures or behaviors that help animals find food, protect themselves from extreme conditions, or escape predators. It provides examples of structural adaptations like a polar bear's fur or a bat-eared fox's big ears, and behavioral adaptations such as penguins huddling together, geese flying south for the winter, or a dormouse hibernating. Other adaptations discussed include camouflage, mimicry, migration, hibernation, and instincts versus learned behaviors.
The document discusses different animal habitats including deserts, forests, jungles, savannas, oceans, and polar regions. It describes the key features of each habitat such as climate, vegetation, seasons, and some example animal species. Different habitats provide animals with the water, food, and shelter they need to survive.
This document discusses physical and behavioral adaptations that help animals survive. Physical adaptations include an animal's body covering, coloration, body parts like beaks and claws, and defenses like venom or quills. Behavioral adaptations are things animals do to survive, either through learned behaviors or instincts, and include hibernation to survive cold weather, migration to travel between seasons, camouflage to blend in with surroundings, and mimicry to disguise their appearance. Adaptations allow animals to respond to life needs in their environments.
The document summarizes a study on the thermal biology and thermoregulation of the anguid lizard Anguis fragilis. Observations were made of their behavior and body temperatures in outdoor enclosures under different weather conditions. Tests using null models, which measure the temperatures attainable in different microhabitats without behavioral thermoregulation, indicated that the lizards' primary reason for being active above ground was thermoregulation. Their body temperatures were significantly higher than temperatures in shaded areas but lower than in open areas, regardless of weather conditions. This suggests the lizards achieved thermoregulation by selecting appropriate microhabitats rather than extensive movement.
This study examined the body temperatures and activity patterns of the giant Solomon Islands skink (Corucia zebrata) in a semi-naturalistic enclosure to better understand its thermal biology. The lizards thermoregulated by selecting microhabitats where body temperatures around 30°C could be maintained. Body temperatures were higher on sunny days but variance was similar between weather conditions. Activity was greater in sunny weather but distance traveled was similar. Enclosure design for captive breeding programs needs thermal and structural diversity to allow appropriate activity and thermoregulation.
This document summarizes observations of the thermoregulatory behavior of the Australian water dragon lizard (Physignathus lesueurii) in relation to body size and social status. The behavior of adult and subadult lizards fit the prediction that basking decreases with increasing operative temperature, but alpha male lizards did not follow this pattern. Subadult lizards engaged in more locomotory movement and were disturbed more frequently than larger lizards, especially in the morning. The results suggest thermoregulation imposes different costs for lizards of different sizes and social statuses.
This study examines the evolutionary rates of three physiological traits related to thermal tolerance—cold tolerance, body temperature, and heat tolerance—in a group of tropical lizards found across a range of thermal environments on Hispaniola. The researchers find that cold tolerance has evolved significantly faster than heat tolerance in these lizards. They suggest this is because behavioral thermoregulation more effectively shields the lizards from selection on upper (heat) tolerance compared to lower (cold) tolerance, since lizards in different environments behaviorally regulate their body temperature during the day to similar levels but nighttime temperatures cannot be fully buffered behaviorally. The findings provide insights into how exposure to selection through an organism's ability to behaviorally regulate temperature influences the pace
37; reptiles, thermoregulation and the environment; reviewRoger Meek
This document summarizes research on thermoregulation in reptiles. It discusses how reptiles interact with their environments to regulate their body temperatures, highlighting examples from lizards, chelonians, and other groups. It examines constraints on reptile thermoregulation from environmental factors like climate and habitat, and costs associated with precise thermoregulation in harsh environments like high altitudes and latitudes. The document aims to provide insights into reptile thermal ecology to help herpetologists with captive breeding projects.
This document summarizes a study that measured the temperatures inside nests of the Australian water dragon (Physignathus lesueurii) over several days in November and December. The study found:
1) Nest temperatures remained relatively constant, between 23-29°C, even as external temperatures varied more widely.
2) The highest nest temperatures were recorded on a sunny day in early December, while overcast days saw maximums below 25°C.
3) Nest temperatures were generally lower than those reported for similar sized tropical lizards, remaining cooler than external temperatures to prevent overheating of eggs.
2013 lima & antonialli junior foraging strategies of the ant ectatomma vizott...Luan Lima
Foraging activity may be limited by
temperature, humidity, radiation, wind, and other abiotic factors, all of which can affect energy costs during foraging. Ectatomma
vizottoi’s biology has only recently been studied, and no detailed information is available on its foraging patterns or diet in the field.
For this reason, and because foraging activity is an important part of the ecological success of social insects, the present study aimed
to investigate E. vizottoi’s foraging strategies and dietary habits. First, we determined how abiotic factors constrained E. vizottoi’s
foraging patterns in the field by monitoring the foraging activity of 16 colonies on eight different days across two seasons. Second,
we characterized E. vizottoi’s diet by monitoring another set of 26 colonies during peak foraging activity. Our results show that E.
vizottoi has foraging strategies that are similar to those of congeneric species. In spite of having a low efficiency index, colonies
adopted strategies that allowed them to successfully obtain food resources while avoiding adverse conditions. These strategies
included preying on other ant species, a foraging tactic that could arise if a wide variety of food items are not available in the
environment or if E. vizottoi simply prefers, regardless of resource availability, to prey on other invertebrates and especially on other
ant species.
The thermal biology of the small sand lizard Liolaemus occipitalis was studied in coastal sand dunes in southern Brazil. L. occipitalis maintained an average body temperature of 30.89°C that varied seasonally and daily depending on microhabitat temperatures. The substrate temperature was the main source for thermoregulation, accounting for most of the variation in lizard body temperatures across seasons. L. occipitalis is a rock-dwelling, thigmothermic, and heliothermic species that regulates its temperature behaviorally based on microclimate conditions.
This document describes a new platform called Arboreal that aims to connect people with project ideas to people with specific skills to collaborate on projects. It discusses features like creating groups for different projects and skills, bidding on project roles, and searching or getting recommendations to find project teammates. It also acknowledges competition from other platforms but notes Arboreal is targeting new projects not just established startups, and that the creators plan to take more design time up front to avoid needing a complete revamp later.
Primates inhabit various forest types across tropical and subtropical regions. Their ecological niches depend on requirements for resources and space. Abiotic factors like climate, water, and minerals affect primate habitats and behaviors, as do biotic factors such as availability of food sources and interactions with other animals including mates, group members, competitors, and predators. Conservation of primate populations faces threats from habitat destruction and hunting.
1) An ecological niche refers to the function a species carries out in its habitat through its use of resources and interactions with other community components.
2) If two species occupy the same exact ecological niche, competition will occur until one species dominates.
3) All species that live in the same habitat have some differences in their niches that allow them to avoid competition, even if aspects of their niches overlap.
Amphibians: What do we know about them?Gururaja KV
Amphibians are vertebrates that can live both on land and in water. They go through a metamorphosis from an aquatic tadpole stage to a terrestrial adult stage. Amphibians are important for ecosystems and human welfare. They indicate environmental changes and provide benefits like controlling pests, serving as traditional medicine, and acting as biological indicators. India is home to 309 amphibian species across 14 families and 55 genera. Ongoing research in India includes studies on reproduction, taxonomy, ecology, and impacts of skin extracts. Conservation efforts aim to protect amphibian habitats and diversity in the Western Ghats.
An ecosystem is defined as a habitat and all the living things within it. A habitat provides living things with food, water, shelter, and space. Most plants and animals in an ecosystem are specially adapted to the conditions of their particular habitat through adaptations like webbed feet, storage organs, or camouflage, which help them survive.
This document summarizes the concept of ecological niche. It discusses niche as a species' habitat requirements, its functional role in an ecosystem, and its position within a local community. Key concepts covered include the fundamental niche representing all conditions a species can persist in, versus the realized niche reflecting interactions with other species; competitive exclusion and limiting similarity regarding how similar niches can be for coexistence; and modes of coexistence such as niche differentiation and dominance hierarchies.
This document discusses human evolution and the timeline of early hominids. It begins by exploring basic questions about human origins and ancestry. It then examines the earliest hominid fossil sites in Africa dating back 6-7 million years, including Sahelanthropus tchadensis from Chad dated to nearly 7 million years old. While the evolutionary relationships between early hominids is still debated, most evidence suggests humans diverged from chimpanzees around 5-7 million years ago. Upright posture evolved in hominids before large brain size. Later sections explore the classification of primates and traits that distinguish hominids from other groups.
The document is a presentation from Miss Thomas' 4th grade class about different animal habitats including polar regions, coniferous forests, grasslands, deserts, tropical forests, oceans, and the animals that can survive in each habitat and how they do so. It includes images from WWF and Apple iPhoto to illustrate the different habitats.
Forests, wetlands, oceans, and deserts are common habitats that support different types of plants and animals. Forests provide habitat for deer and many other species among the trees and plants. Wetlands are covered with water and are home to animals like bullfrogs. Oceans contain salt water and various fish live in the ocean habitat. Deserts receive little rain, can be hot during the day, and certain animals have adapted to live in the dry desert environment.
Class IV - Adaptations-How Animals SurviveLearnRoots
The document discusses how animals have adapted to survive in different environments. It describes how animals are classified based on whether they have a backbone or not. It then covers the main groups of vertebrates - fish, amphibians, reptiles, birds, and mammals. For each group, it outlines key characteristics like how they breathe, their temperature regulation, and examples. It also discusses how animals have adapted to live in different habitats like land, water, trees, and air. Finally, it covers adaptations related to food sources, protection, and endangered species.
The document discusses where different types of animals live. Land animals live on earth, aquatic animals live in water, and air terrestrial animals fly in the sky. It lists land animals, aquatic animals, and air terrestrial animals.
The document discusses animal adaptations, defining them as body structures or behaviors that help animals find food, protect themselves from extreme conditions, or escape predators. It provides examples of structural adaptations like a polar bear's fur or a bat-eared fox's big ears, and behavioral adaptations such as penguins huddling together, geese flying south for the winter, or a dormouse hibernating. Other adaptations discussed include camouflage, mimicry, migration, hibernation, and instincts versus learned behaviors.
The document discusses different animal habitats including deserts, forests, jungles, savannas, oceans, and polar regions. It describes the key features of each habitat such as climate, vegetation, seasons, and some example animal species. Different habitats provide animals with the water, food, and shelter they need to survive.
This document discusses physical and behavioral adaptations that help animals survive. Physical adaptations include an animal's body covering, coloration, body parts like beaks and claws, and defenses like venom or quills. Behavioral adaptations are things animals do to survive, either through learned behaviors or instincts, and include hibernation to survive cold weather, migration to travel between seasons, camouflage to blend in with surroundings, and mimicry to disguise their appearance. Adaptations allow animals to respond to life needs in their environments.
The document summarizes a study on the thermal biology and thermoregulation of the anguid lizard Anguis fragilis. Observations were made of their behavior and body temperatures in outdoor enclosures under different weather conditions. Tests using null models, which measure the temperatures attainable in different microhabitats without behavioral thermoregulation, indicated that the lizards' primary reason for being active above ground was thermoregulation. Their body temperatures were significantly higher than temperatures in shaded areas but lower than in open areas, regardless of weather conditions. This suggests the lizards achieved thermoregulation by selecting appropriate microhabitats rather than extensive movement.
This study examined the body temperatures and activity patterns of the giant Solomon Islands skink (Corucia zebrata) in a semi-naturalistic enclosure to better understand its thermal biology. The lizards thermoregulated by selecting microhabitats where body temperatures around 30°C could be maintained. Body temperatures were higher on sunny days but variance was similar between weather conditions. Activity was greater in sunny weather but distance traveled was similar. Enclosure design for captive breeding programs needs thermal and structural diversity to allow appropriate activity and thermoregulation.
This document summarizes observations of the thermoregulatory behavior of the Australian water dragon lizard (Physignathus lesueurii) in relation to body size and social status. The behavior of adult and subadult lizards fit the prediction that basking decreases with increasing operative temperature, but alpha male lizards did not follow this pattern. Subadult lizards engaged in more locomotory movement and were disturbed more frequently than larger lizards, especially in the morning. The results suggest thermoregulation imposes different costs for lizards of different sizes and social statuses.
This study examines the evolutionary rates of three physiological traits related to thermal tolerance—cold tolerance, body temperature, and heat tolerance—in a group of tropical lizards found across a range of thermal environments on Hispaniola. The researchers find that cold tolerance has evolved significantly faster than heat tolerance in these lizards. They suggest this is because behavioral thermoregulation more effectively shields the lizards from selection on upper (heat) tolerance compared to lower (cold) tolerance, since lizards in different environments behaviorally regulate their body temperature during the day to similar levels but nighttime temperatures cannot be fully buffered behaviorally. The findings provide insights into how exposure to selection through an organism's ability to behaviorally regulate temperature influences the pace
37; reptiles, thermoregulation and the environment; reviewRoger Meek
This document summarizes research on thermoregulation in reptiles. It discusses how reptiles interact with their environments to regulate their body temperatures, highlighting examples from lizards, chelonians, and other groups. It examines constraints on reptile thermoregulation from environmental factors like climate and habitat, and costs associated with precise thermoregulation in harsh environments like high altitudes and latitudes. The document aims to provide insights into reptile thermal ecology to help herpetologists with captive breeding projects.
This document summarizes a study that measured the temperatures inside nests of the Australian water dragon (Physignathus lesueurii) over several days in November and December. The study found:
1) Nest temperatures remained relatively constant, between 23-29°C, even as external temperatures varied more widely.
2) The highest nest temperatures were recorded on a sunny day in early December, while overcast days saw maximums below 25°C.
3) Nest temperatures were generally lower than those reported for similar sized tropical lizards, remaining cooler than external temperatures to prevent overheating of eggs.
2013 lima & antonialli junior foraging strategies of the ant ectatomma vizott...Luan Lima
Foraging activity may be limited by
temperature, humidity, radiation, wind, and other abiotic factors, all of which can affect energy costs during foraging. Ectatomma
vizottoi’s biology has only recently been studied, and no detailed information is available on its foraging patterns or diet in the field.
For this reason, and because foraging activity is an important part of the ecological success of social insects, the present study aimed
to investigate E. vizottoi’s foraging strategies and dietary habits. First, we determined how abiotic factors constrained E. vizottoi’s
foraging patterns in the field by monitoring the foraging activity of 16 colonies on eight different days across two seasons. Second,
we characterized E. vizottoi’s diet by monitoring another set of 26 colonies during peak foraging activity. Our results show that E.
vizottoi has foraging strategies that are similar to those of congeneric species. In spite of having a low efficiency index, colonies
adopted strategies that allowed them to successfully obtain food resources while avoiding adverse conditions. These strategies
included preying on other ant species, a foraging tactic that could arise if a wide variety of food items are not available in the
environment or if E. vizottoi simply prefers, regardless of resource availability, to prey on other invertebrates and especially on other
ant species.
The thermal biology of the small sand lizard Liolaemus occipitalis was studied in coastal sand dunes in southern Brazil. L. occipitalis maintained an average body temperature of 30.89°C that varied seasonally and daily depending on microhabitat temperatures. The substrate temperature was the main source for thermoregulation, accounting for most of the variation in lizard body temperatures across seasons. L. occipitalis is a rock-dwelling, thigmothermic, and heliothermic species that regulates its temperature behaviorally based on microclimate conditions.
1) Female speckled tortoises (Homopus signatus) in South Africa were observed over 29 days in early spring to understand how they cope with low environmental temperatures during their active feeding season.
2) The tortoises showed a unimodal daily activity pattern, but individual tortoises were only active for about 4.5 hours per day on average. They spent up to 73% of their active time basking, mostly under shrubs.
3) On colder days, the tortoises spent a higher percentage of their active time basking, indicating they use basking more to absorb heat when temperatures are low. Their feeding time was very low at only 24 minutes per day, likely
1. The study measured the respiratory rates, body temperatures, and behaviors of captive bearded dragons (Pogona vitticeps) during periods with and without handling.
2. Respiratory rates increased significantly after handling, but returned to baseline levels once handling stopped. Body temperature increases respiration at similar rates whether the lizards were handled or not.
3. The results suggest that handling induces stress in bearded dragons, shown by elevated respiratory rates, even if the lizards appear habituated to frequent human contact. This has implications for the welfare of reptiles in captive breeding and education programs that involve frequent handling.
1. The document discusses how different organisms regulate their body temperatures in response to variations in environmental temperature. It focuses on plants, microbes, and animals.
2. Most organisms can only photosynthesize or perform other biological functions within a narrow temperature range. The document provides examples of how plants and microbes are adapted to different optimal temperature ranges depending on their environment.
3. Organisms regulate their body temperature using various mechanisms to gain, lose, or maintain heat, including metabolic heat production, conduction, convection, radiation, and evaporation. Endothermic animals like birds and mammals internally produce heat through metabolism, while ectothermic animals rely more on external heat sources.
transpiration in plants , introduction, historical background, definition and types , rate of transpiration , materials, methedology and working plans , observation and result , discussion and conclusion .
This study compared the thermoregulation of Chinampo cattle, Holstein cattle, and Jersey cattle in a hot, arid region of northwest Mexico from June to December. Rectal temperature and respiratory rate were recorded for each breed. The results showed that Holstein cattle had the highest rectal temperatures, especially in September, indicating they were least tolerant to heat stress. Chinampo cattle maintained rectal temperatures and respiratory rates closest to normal limits and had the lowest physiological responses to increasing heat stress, showing they were most tolerant to high temperatures.
This document summarizes observations of movements, mating, and parturition in a female aspic viper (Vipera aspis) in western France over two years. The female was observed basking near her hibernaculum in early spring both years. In 2015, she was observed mating with another viper in April and giving birth to an estimated 6 offspring in September, consistent with the species' gestation period. Post-parturition, she was sighted moving between hibernaculum areas until late fall. No vipers were sighted near the hibernaculum over summer, suggesting a seasonal migration. The observations provide information about the species' thermoregulation and reproductive behaviors.
Lizards are vertebrate ectotherms, which like other animals maintain their body temperature (Tb) within a relatively narrow range in order to carry out crucial physiological processes during their life cycle. The preferred body temperature (Ts) that a lizard voluntarily selects in a laboratory thermal gradient
provides a reasonable estimate of what a lizard would attain in the wild with a minimum of associate costs in absence of constraints for thermoregulation
Experiments with duckweed–moth systems suggest thatglobal wa.docxelbanglis
Experiments with duckweed–moth systems suggest that
global warming may reduce rather than promote
herbivory
TJISSE VAN DER HEIDE, RUDI M. M. ROIJACKERS, EDWIN T. H. M. PEETERS AND
EGBERT H. VAN NES
Department of Environmental Sciences, Aquatic Ecology and Water Quality Management group, Wageningen University,
Wageningen, The Netherlands
SUMMARY
1. Wilf & Labandeira (1999) suggested that increased temperatures because of global
warming will cause an increase in herbivory by insects. This conclusion was based on the
supposed effect of temperature on herbivores but did not consider an effect of temperature
on plant growth.
2. We studied the effect of temperature on grazing pressure by the small China-mark moth
(Cataclysta lemnata L.) on Lemna minor L. in laboratory experiments.
3. Between temperatures of 15 and 24 �C we found a sigmoidal increase in C. lemnata
grazing rates, and an approximately linear increase in L. minor growth rates. Therefore, an
increase in temperature did not always result in higher grazing pressure by this insect as
the regrowth of Lemna changes also.
4. At temperatures below 18.7 �C, Lemna benefited more than Cataclysta from an increase in
temperature, causing a decrease in grazing pressure.
5. In the context of global warming, we conclude that rising temperatures will not
necessarily increase grazing pressure by herbivorous insects.
Keywords: Cataclysta, grazing, herbivory, Lemna, temperature
Introduction
Duckweeds (Lemnaceae) are often abundant in dit-
ches and ponds (Landolt, 1986). Especially when
nitrogen and phosphorus concentrations in the water
column are high, the surface area can become covered
with dense floating mats of duckweed (Lüönd, 1980,
1983; Portielje & Roijackers, 1995). These mats have
large impacts on freshwater ecosystems, restricting
oxygen supply (Pokorny & Rejmánková, 1983), light
availability of algae and submerged macrophytes
(Wolek, 1974) and temperature fluxes (Dale &
Gillespie, 1976; Landolt, 1986; Goldsborough, 1993).
These changed conditions often have a negative effect
on the biodiversity of the ecosystem (Janse & van
Puijenbroek, 1998). Other free-floating plants such as
red water fern (Azolla filiculoides), water hyacinth
(Eichhornia crassipes) and water lettuce (Pistia stratiotes)
often cause serious problems in tropical and sub-
tropical regions (Mehra et al., 1999; Hill, 2003).
Various species of herbivorous insects consume
free-floating macrophytes. Several species of weevils
(Coleoptera: Curculionidae) are able to consume large
amounts of red water fern, water hyacinth and water
lettuce (Cilliers, 1991; Hill & Cilliers, 1999; Aguilar
et al., 2003), while the larvae of the semi-aquatic Small
China-mark moth (Cataclysta lemnata) are capable of
removing large parts of floating cover of Lemnaceae
covers (Wesenberg-Lund, 1943). Duckweed is not
only used as food source, but also as building material
Correspondence: Rudi M. M. Roijacker ...
Investigation into the existence of Thermal Sensory Capabilities of Dung Beetlesjsenia
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Biology 205 discusses how organisms regulate and adapt to changing temperatures. It explains that most species perform best within a narrow temperature range and have evolved various regulatory mechanisms. These include using morphology, pigmentation, burrowing, and behavior to balance heat gain and loss. The lecture also distinguishes between ectothermic animals, which rely on external heat sources, and endothermic animals, which generate their own metabolic heat to maintain constant body temperatures. Many organisms enter resting stages like hibernation to avoid extreme temperatures.
This study examined the effects of soil water temperature on root hydraulic resistance (Rh) in six species of Iberian pines. Rh increased for all species as temperature decreased from 30°C to 0°C. Mountain pine species showed consistently higher Rh values than coastal pine species at all temperatures tested. Mountain pines also displayed a more pronounced increase in Rh in response to decreasing temperatures, with their Rh response curves exhibiting a sharper inflection point between 20-10°C. These differences in hydraulic behavior between mountain and coastal pine species support their observed spatial segregation patterns along altitudinal gradients in the Iberian Peninsula, and may influence how these species respond to future climate change.
This document summarizes a basic biology practicum report on the influence of temperature on organism activity. It was conducted by a student named Jeny ayu hardiah ningrum in December 2011. The practicum involved observing the operculum movement frequency of goldfish (Cyprinus carpio) in warm water and cold water with ice cubes over 5 minutes to determine how temperature affects chemical reactions and activity in the body. The purpose was to compare oxygen usage speeds in different temperatures. The practicum aimed to provide knowledge on how temperature influences organism processes and help with fish care.
This document summarizes observations of post-hibernation movements of four reptile species - Hierophis viridiflavus, Natrix natrix, Vipera aspis, and Lacerta bilineata - around a hibernaculum in western France between late March and late May. Most sightings occurred in April, gradually declining later that month, with no reptiles seen after May 28th. The reptiles remained close to the hibernaculum for approximately 45 days before dispersing. Movement patterns and areas used were analyzed and discussed in relation to habitat characteristics and previous studies.
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42; physignathus lesueurii predation (natural history note)Roger Meek
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2) Observations included 8 successful predation events where the Water Dragon captured the Grass Skink from distances up to 7 meters away.
3) Unsuccessful predation attempts by Water Dragons on Grass Skinks were also observed, with the skinks escaping into vegetation.
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This document summarizes two observations of aggression in water monitors (Varanus salvator) in Sri Lanka. In the first observation, a large monitor attacked and chased off a smaller monitor basking on the bank of a narrow waterway. In the second observation, two large monitors were seen wrestling in the water in a typical combat embrace. This suggests monitors may display aggression over territory even in aquatic environments, which had not been reported previously. The document also summarizes an observation of a Philodryas patagoniensis snake that had preyed upon and consumed a venomous snake, possibly a young one, based on the presence of a fang in its feces. This suggests P. patagoniensis may occasionally
Researchers successfully incubated two clutches of reptile eggs under fluctuating temperatures rather than a constant temperature. The eggs hatched and produced healthy hatchlings. The study showed that reptile eggs can develop under more natural fluctuating temperatures rather than the traditional constant temperatures used in captivity.
The document summarizes a study that analyzed the relationship between body mass and carapace length in four chelonian species: Testudo graeca, Testudo hermanni, Emys orbicularis, and Chrysemys scripta. The study found allometric equations describing this relationship for each species, with carapace length generally proportional to body mass raised to the 0.34 power. A comprehensive equation for all species combined supported this finding.
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This paper reexamines data on the relationship between carapace length and body mass in the desert tortoise (Testudo sulcata) from a previous study. The authors calculate new allometric equations using the original data and find exponents of 0.36 and 0.39, which disagree with the previous study's calculation of 0.91. These new exponents are closer to what would be expected based on other research on chelonian allometry. The authors conclude the previous study likely contained errors in their calculations and analysis of this tortoise species' measurements.
This document summarizes the use of cryosurgery to treat skin disorders in two lizards and one turtle. Cryosurgery, which uses extremely low temperatures to destroy unwanted tissue, was used to successfully treat a large growth on a green lizard, a skin lesion on a tegu lizard, and an infected swelling behind the ear of a box turtle. The results indicate that cryosurgery may be a valuable surgical tool for treating skin disorders and infections in reptiles.
66;road mortalities of amphibians hj 22(1)_pp_51-58_ms_11-55[1]Roger Meek
This study monitored amphibian roadkill over six years on low-traffic roads in western France. The common toad and agile frog made up the majority of roadkill at 39% and 25.4% respectively. Roadkill patterns were associated with amphibian migration and habitat near roads. Higher roadkill occurred near woodlands/wetlands and after rainfall, related to migration and foraging behavior. Traffic volume did not correlate with roadkill, but roadkill increased with longer amphibian migration distances.
1) Over a seven year period in Western France, 36 whip snakes (Hierophis viridiflavus) suffered mortality from anthropogenic sources such as humans, dogs, and cats.
2) Humans killed over half of the snakes, particularly subadult/hatchling snakes. Dogs and cats also killed snakes, with dogs killing both adult and young snakes and cats only killing young snakes.
3) Mortality patterns varied by age class, with most adult snake deaths occurring in May during the breeding season and most subadult/hatchling deaths in August and September during dispersal from nest sites.
1) A Solomon Island skink (Corucia zebrata) showed signs of a skin infection and was treated with the antibiotic Baytril. After initially recovering, the skink's condition gradually declined despite a good appetite.
2) It is suspected that the antibiotic treatment may have adversely affected the skink's intestinal microbe and nematode populations, causing maldigestion.
3) 'Artificial coprophagy' was induced by smearing mealworms with cagemates' feces, which the skink consumed. This helped restore the intestinal fauna and the skink regained normal weight within two months.
1) The study tested whether three species of monitor lizards (Varanus spp.) showed evidence of association learning by recording how long it took them to locate food over repeated trials.
2) Results showed that the time to locate food decreased with the number of trials for two of the three species, providing evidence of association learning.
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ESR spectroscopy in liquid food and beverages.pptxPRIYANKA PATEL
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
Immersive Learning That Works: Research Grounding and Paths ForwardLeonel Morgado
We will metaverse into the essence of immersive learning, into its three dimensions and conceptual models. This approach encompasses elements from teaching methodologies to social involvement, through organizational concerns and technologies. Challenging the perception of learning as knowledge transfer, we introduce a 'Uses, Practices & Strategies' model operationalized by the 'Immersive Learning Brain' and ‘Immersion Cube’ frameworks. This approach offers a comprehensive guide through the intricacies of immersive educational experiences and spotlighting research frontiers, along the immersion dimensions of system, narrative, and agency. Our discourse extends to stakeholders beyond the academic sphere, addressing the interests of technologists, instructional designers, and policymakers. We span various contexts, from formal education to organizational transformation to the new horizon of an AI-pervasive society. This keynote aims to unite the iLRN community in a collaborative journey towards a future where immersive learning research and practice coalesce, paving the way for innovative educational research and practice landscapes.
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
Authoring a personal GPT for your research and practice: How we created the Q...Leonel Morgado
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...Leonel Morgado
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
1. - 1 -
Bull. Soc. Herp. Fr. (2011) 138 : 1-11
Aspects of the thermal ecology of
the European tree frog Hyla arborea (Linnaeus, 1758)
(Anura: Hylidae) in Western France
by
Roger Meek
7 rue Georges Clemenceau, 85400 Chasnais, France
Rogermeek85@aol.com
Summary – Body temperatures of the tree frog Hyla arborea were measured over a six-year period
during overcast and sunny weather in Vendée of Western France. Body temperatures were higher dur-
ing sunny weather but there was no difference in body temperature variance. Body temperature vari-
ance was lower in comparison to the variance of leaf temperatures in sunlit areas but in agreement with
leaf temperature variance in shaded areas irrespective of weather conditions. Regression analysis of
body temperatures with leaf temperatures in shade or open locations during both sunny and cloudy
weather indicated the closest association was with shaded leaf temperature regardless of weather con-
ditions. Frogs were located at median distances of 2-12 m from the nearest water mostly in shaded
areas, but a smaller number were observed in sunlit areas during sunny weather in mid-afternoon. The
results suggest control of body temperature in H. arborea by microhabitat selection, with shaded areas
selected to avoid potentially critical high temperatures during sunny weather. However, occasional
basking in open locations, even during hot weather, suggests an attempt to elevate body temperature.
Key-words: Hyla arborea, body temperatures, weather conditions, microhabitat selection.
Résumé – Aspects de l’écologie thermique de la Rainette européenne Hyla arborea (Linnaeus,
1758) (Anura: Hylidae) dans l’Ouest de la France. Les températures corporelles de la rainette Hyla
arborea ont été mesurées sur le terrain sur une période de six ans par temps couvert et ensoleillé en
Vendée. La température du corps était plus élevée par temps ensoleillé mais il n’y avait pas de différen-
ce dans la variance de la température corporelle. La variance de la température corporelle était infé-
rieure par rapport à la variance de la température des feuilles dans les zones ensoleillées, mais compa-
rable à la variance de la température des feuilles dans les zones ombragées, indépendamment des
conditions météorologiques. L’analyse de régression de la température du corps avec les températures à
l’ombre des feuilles ou des lieux ouverts durant les journées ensoleillées et nuageuses ont indiqué une
association plus proche avec la température des feuilles ombragées, indépendamment des conditions
météorologiques. Les grenouilles étaient situées à des distances médianes de 2-12m du point d’eau le
plus proche pour la plupart dans des zones ombragées, mais un plus petit nombre a été observé dans
des zones ensoleillées par temps ensoleillé en après-midi. Les résultats suggèrent le contrôle de la tem-
pérature corporelle chez H. arborea par la sélection du microhabitat, avec des zones ombragées dans
les arbres sélectionnés afin déviter les situations potentiellement critiques des températures élevées par
temps ensoleillé. Toutefois, des expositions occasionnelles dans des endroits ouverts, même par temps
chaud, suggèrent une tentative pour accroitre la température corporelle.
Mot-clés : Hyla arborea, températures corporelles, conditions météorologiques, sélection du microha-
bitat.
2. - 2 -
I. INTRODUCTION
The body temperature of ectotherms is a key factor in their ecology since many physi-
ological functions are temperatures dependent – e.g. locomotory movement, digestion and
growth (Huey 1991). In amphibians the permeable integument and subsequent high rates
of evaporative water loss imposes the dual regulation of attempting to maintain body tem-
peratures that are optimal for physiological processes whilst maintaining water balance. This
may constrain body temperature selection but in the presence of water many amphibians are
able to bask with evaporative water losses contributing to body temperature control (Shoe-
maker et al. 1992, Snyder & Hammerson 1993). Basking in water frogs of the Pelophylax
lessonae/ridibunda/perezi complex beside ponds or other water bodies even when environ-
ment temperatures are high is possible because of the immediate access to water (e.g. Meek
1983). When hydration is a limiting factor evaporative water loss may be controlled through
postures, employment of special skin secretions or microhabitat selection (review in Wells
2007), adaptations often found in tree frogs. Arboreal habitats are particularly challenging
for amphibian physiology, especially when the climate is hot with low humidity. This may
impose constraints on achieving body temperatures that are optimal for physiological pro-
cesses, for example, locomotory capacity has been found to be maximal at mean field body
temperature in tree frogs (Knowles & Weigl 1990).
The tree frog Hyla arborea is a widespread species in Europe although in some areas
it has been reported to be in decline (e.g. Fog 1995, Baker 1997). It is listed on Appendix
II of the Berne Convention and Annex IV of the EU Natural Habitats Directive. It can be a
difficult species to locate even when detected from calls, which is temperature dependent
(Pellet & Schmidt 2005), but additionally year to year numbers in some areas differ consid-
erably due to migratory movement and/or reproductive success (Baumgartner 1986, Stumpel
1987, Pellet et al. 2006). Little information on field body temperature is currently available
although according to Stumpel (1987, 1993) it does occasionally bask. This paper presents
baseline information on aspects of H. arborea thermal ecology in Vendée, western France
from data collected over a six-year period mainly between May-September, the months with
lowest rainfall/humidity and highest temperatures. During summer ambient air temperatures
may regularly exceed 30-35o
C and humidity levels descend to less than 40%.
3. - 3 -
II. MATERIALS AND METHODS
Data were opportunistically collected from 2004 and 2009 in gardens and surrounding
woodlands of the villages of Chasnais, Lairoux, and Saint-Denys-du-Payre (46o
27’N). Body
temperatures (Tb) were recorded from 108 tree frogs, 86 during sunny weather, 22 when
the weather was overcast or mostly overcast (s.v. length taken after Tb was recorded gave
mean ± standard deviation = 39.3 ± 5.1 mm). A further 6 were located during sunny weather
in summer but not measured for Tb although their distances from the nearest water bodies
were recorded. Most frogs were located from vocal calls; others were found visually on the
leaves of bushes or trees. All individuals measured were close to the ground (3-4 metres) in
both shaded and sunlit areas. Body temperatures are defined as skin surface temperatures
recorded with an Electronique Frontal infrared detector (model TS112) to within 10-20 mm
from the skin surface. This instrument is non-invasive and detects infrared energy emitted
from the skin surface and has an error of less than 0.01o
C. There will be, however, some
additional error due to the emissivity of H. arborea skin and also due to the distance that
the device is held from the skin surface, as it is possible to measure some of the surrounds.
The 10-20 mm distance employed here and size of the frogs minimizes the latter potential.
Measurements were made as quickly as possible, usually within several seconds from initial
sightings. No handling was involved; the infrared detector was pointed at the animal and its
skin surface temperature recorded. Frogs appeared to respond only to measurement if the
instrument touched the skin surface and on the few occasions when this occurred the data
point was ignored. To provide insight into the available range of temperatures, several leaf
surface temperatures next to the frog were simultaneously recorded in the same way, both in
shade (TLShade) and in fully sunlit areas (TLSun) and the means of both used for comparison
with Tb. During overcast or mostly overcast weather TLSun is defined as leaves on the margins
of fully shaded and fully exposed areas. Animals recorded as situated in full sun or partial
sun (part of the body in sunshine) does not necessarily imply active basking. For instance, a
shift in position from a partial or shaded area to sunlit location does not always require ani-
mal movement, it can be a consequence of a shift in the angle of the sun.
Statistical analysis. Body temperatures were tested for normality using the Anderson-
Darling test. This test assumes the null hypothesis and the results showed no significant
departure from normality either during overcast weather (a2
= 0.38, p = 0.36) or when sunny
4. - 4 -
and hot (a2
= 0.69, p = 0.07). Leaf temperatures were normally distributed during sunny
weather but non-parametric when the weather was overcast and hence Mann Whitney U-tests
were used. Non-parametric tests for equality of variance were made with Levene`s test and
F-tests when data were parametric. The adjusted r2
values are shown, which is independent
of sample size – increases in sample size alone will not increase the r2
value. Tests were made
for thermoregulation using regression analysis of body temperature with leaf temperatures.
In this test thermoconformity requires a coefficient of 1, which was evaluated using t-tests at
n-2 degrees of freedom (Bailey 1981).
III. RESULTS
Frogs were measured between 1030-2215 hrs but the majority were found in the after-
noon; median =1500hrs, interquartile range = 1350-1823 hrs. Table I shows the distances
they were located from water bodies during different weather conditions and season. The
median distances from the nearest pond during sunny weather and overcast weather was
not significant (w = 5462.5, p = 0.21). The distances recorded during spring (late April-
May) were significantly shorter than found in summer (June-early October; w = 1035.0,
p = 0.005).
Microhabitat selection. During sunny weather most animals were found in shaded
locations on the leaves of trees or other plants (60.5%) followed by partially shaded areas
(27.9%). Only 11.6% were located in direct sunshine. When the weather was overcast a rela-
tively greater number of frogs were found in partially sunlit locations (55.6%) compared to
sunny weather (z = 1.998, p = 0.045; Q = 0.022). Table II shows the changes in exposure to
Table I: Distances between H. arborea and water bodies during different weather and seasons.
Tableau I : Distances entre H. arborea et les plans d’eau selon la météorologie et la saison.
median interquartile range n p
sunny 12 5 - 13 92
overcast 9.5 5 - 13 22 n.s.
spring 2 2 - 13 25
summer 12 7 - 13 89 0.005
5. - 5 -
sunlight with time of day when the data are sectioned into hourly time periods. Due to small
sample sizes, data for animals found after 2000 hrs have been pooled. Data are absent for
several of the hourly periods during overcast weather and indicated as ND. When the weath-
er was sunny most exposure to sunshine was between 1400-1600hrs (partial sun = 42.4%; in
full sun = 30.3%).
Body temperatures. During sunny weather Tb (mean±standard deviation = 25.4 ± 3.7,
range = 18.9-32.9o
C) was higher than when overcast (mean±standard deviation = 21.9 ± 3.5,
range = 14.0-25.2o
C) with the difference significant (F(1,106) = 16.1, p < 0.0001). Variance of
Tb was not significantly different between weather conditions (F = 1.73, p = 0.15). Frequen-
cy histograms of Tbs during different weather are shown in Figure 1.
Body temperatures in relation to TLSun and TLShade. Overcast weather Tb was signifi-
cantly lower than TLSun (mean ± standard deviation = 26.6 ± 6.3o
C; w = 345.0, p = 0.0004)
but not significantly different from TLShade (mean ± standard deviation = 20.7 ± 2.2o
C;
w = 526.0, p = 0.47). Sunny weather Tb was significantly lower than TLSun (mean ± standard
deviation = 32.2 ± 4.7o
C; F(1,170) = 110.9, p < 0.0001) but higher than TLShade (mean ± stan-
dard deviation = 23.9 ± 4.1o
C; F(1, 170) = 5.21, p = 0.024. When the weather was overcast vari-
Table II: Hourly differences in exposure (percent) to sunshine in H. arborea during different weather
conditions. ND indicates no data available.
Tableau II : Différences horaires d’exposition (pourcentage) au soleil chez H. arborea sous différentes
conditions météorologiques. ND indique l’absence de données disponibles.
Sun
(∑n = 86)
Overcast
(∑n = 22)
Time of day
(x 100)
shade
partial
shade
sun n shade
partial
shade
sun n
10 - 11 71.4 28.6 0.0 7 ND ND ND 0
11 - 12 100.0 0.0 0.0 4 75.0 25.0 0.0 4
12 - 13 100.0 0.0 0.0 6 75.0 25.0 0.0 4
13 - 14 100.0 0.0 0.0 3 75.0 25.0 0.0 4
14 - 15 28.6 52.3 19.1 21 0.0 100.0 0.0 1
15 - 16 38.8 23.1 46.1 13 100.0 0.0 0.0 3
16 - 17 60.0 40.0 0.0 5 100.0 0.0 0.0 1
17 - 18 100.0 0.0 0.0 4 ND ND ND 0
18 - 19 100.0 0.0 0.0 8 33.4 66.6 0.0 3
19 - 20 100.0 0.0 0.0 6 ND ND ND 0
20 > 55.5 44.4 0.0 9 0.0 100.0 0.0 3
6. - 6 -
ance of Tb was significantly smaller than variance of TLSun (Levene’s test L = 4.32, p = 0.04)
but in agreement with variance of TLShade (L = 2.76, p = 0.10). During sunny weather a simi-
lar statistical pattern was found with Tb variance significantly smaller than TLSun variance
(F = 0.65, p = 0.04) but not significantly different from TLShade variance (F = 0.83, p = 0.38).
Regressions of Tb versus TLShade and TLSun. When the weather was hot and sunny regres-
sion analysis indicated a strong association of Tb with TLShade and gave:
Tb = 6.6 + 0.78 ± 0.05 TLShade (r2
= 73.2%) (1)
However, the test against a hypothetical value of 1 indicated a significant departure from
thermoconformity (t = 4.31, p < 0.0001). Less agreement was found with TLSun (regression
Figure 1: Frequency distributions of H. arborea body temperatures during sunny and overcast wea
ther.
Figure 1 : Distribution des températures corporelles chez H. arborea par temps ensoleillé et nuageux.
7. - 7 -
coefficient = 0.42±0.07; r2
= 26%). When the weather was overcast the closest association
was again found with TLShade with:
Tb = -2.6 + 1.16 ± 0.13TLShade (r2
= 77.9%) (2)
with the regression not significantly different from 1 (t = 1.23, p = 0.22). The regres-
sion coefficient TLSun at this time was 0.37 ± 0.06 (r2
= 64.7%). Figure 2 shows graphs of
Figure 2: Graphs of body temperatures plotted against shaded leaf temperatures during sunny and
overcast weather. The lines running through the data represent equations (1) for sunny weather and (2)
for overcast weather given in the text and the broken lines that expected from a hypothetical thermo-
conformer.
Figure 2 : Graphiques de la température corporelle déterminée en fonction de la température des feuilles
ombragées par temps ensoleillé et nuageux. Les lignes continues représentent les droites ajustées (1)
par temps ensoleillé et (2) par temps couvert (équations indiquées dans le texte) et la ligne discontinue
indique le profil hypothétique d’un ``thermoconformer``.
8. - 8 -
Tb plotted against TLShade under cloudy and sunny weather with regression lines calculated
from equations (1) and (2). The broken lines represent that expected of a hypothetical ther-
moconformer and indicate departure from thermoconformity during sunny weather is a con-
sequence of elevated Tb in relation to TLShade when TLShade is low with Tb lower than TLShade
when TLShade is high.
IV. DISCUSSION
The results suggest that Tb in H. arborea is regulated mainly by selection of microenvi-
ronments; the selection of leaves that are in shaded areas when the weather is sunny and hot
with some limited movement onto leaves in more open areas during hot sunny weather (per-
haps indicating basking behaviour), a trend that increased when the weather was overcast.
Therefore in either sunny or overcast weather TLShade was the best predictor of Tb, which is
in good agreement with other studies of tree frog Tbs (e.g. Wygoda & Williams 1991). This
is not always the case. For example, in Hyla arenicolor, a basking tree frog living beside
permanent waterways in North America, Tb is independent of air temperature and other envi-
ronmental variables (Snyder & Hammerson 1993). Thermoregulation in ectotherms depends
on spatial and temporal availability of suitable microclimates and hence hourly or seasonal
Tb can vary as a consequence (Angilletta et al. 2002). Observations of diurnal movement in
H. arborea indicated some limited activity in trees including, apparently, shade seeking as a
consequence of solar movement resulting in lower Tb variance in respect to variance of TLSun.
Selection of shaded areas in a sunny and hot environment may enable increased activity and
access to food and hence net energy gain, as has been shown in other ectotherms (Riechert &
Tracy 1975, Huey 1991).
In tree frogs the impact of evaporative water loss on an ability to thermoregulate in the
absence of water is mitigated by reduced rates of evaporative water loss (Wells 2007). In
certain hylids this has been shown to be as much as 7 times lower than in typical frogs (e.g.
Hyla arenicolor; Snyder & Hammerson 1993) facilitating long-term occupancy of elevated
habitats at high Tbs (e.g. Hyla cinerea; Wygoda & Williams 1991). Tree frogs, however, must
at some point undertake some migratory movement, either to suitable water bodies for repro-
duction or hibernation. In this study, H. arborea were located at much shorter distances from
water bodies than found in H. arborea in the Netherlands (up to 300 m; Stumpel 1987) and
9. - 9 -
Switzerland (more than 800 m: Pellet et al. 2006). In the latter study tree frogs migrated
from the breeding area to summer territories where movement was more limited, which is
consistent with the Stumpel (1987) study and the present findings. Road-killed H. arborea in
the study area were mostly found between October and December (59.5% of 42 individuals),
the majority after rain (85.7%); less road-kill (14.6%) was found between April and June.
The period between October and November has the highest precipitation and it is therefore
possible that the hotter and drier Vendéen climate and/or abundance of water bodies may
impact on movement behaviour with hydric conditions particularly constraining longer dis-
tance movement.
Elevated Tbs confer the same physiological benefits to amphibians as they do in reptiles
(Brattstrom 1979, Duellman & Trueb 1986). Physiological performance has been shown to
be sensitive to Tb in anurans (Navas 1996) including tree frogs, for instance, jump distances
in North American tree frogs increased over temperatures from 0-35o
C (John-Alder et al.
1989). Elevated Tbs increase growth in juvenile amphibians and in adult’s food turnover,
which enhances reproduction (Wells 2007). The Tbs recorded for H. arborea, although at
the lower end of the Tb range for hylids, are in general agreement with those found for North
American species (e.g. Wygoda & Williams 1991, Lillywhite et al. 1998, Tracy & Chris-
tian 2005). For example, H. cinerea has been observed in sunlight with Tbs as high as 36o
C
(Wygoda & Williams 1991), which exceeds the maximum of 32.9o
C found in this study.
The Australian tree frogs (Litoria sp.) have greater resistance to water loss than hylids and
experience Tbs up to 38o
C with the waterproof tree frogs (e.g. genus Chiromantis and Phyl-
lomedusa) even higher (Shoemaker et al. 1987, Geise & Linsenmair 1988, Wells 2007). The
mean diurnal Tb of H. arborea in sunny weather was almost identical to those found in sym-
patric Pelophylax lessonae that were measured whilst basking beside ponds or on pond sur-
faces (mean ± standard deviation = 25,9 ± 2,5o
C, n = 23) and higher than in a small sample
of sympatric Rana dalmatina diurnally foraging in woodland (24,1 ± 4,6o
C, n = 9). However,
diurnal Tbs in sympatric B. bufo were higher (mean = 30,-2o
C) and in agreement with shaded
air temperatures close to the ground (Meek & Jolley 2006). The ability of H. arborea to oper-
ate in arboreal habitats presumably reduces predation from terrestrial predators and competi-
tion from sympatric terrestrial anurans, for instance from P. lessonae, which are abundant
around water bodies throughout the active year.
10. - 10 -
Acknowledgments – Dr Roger Avery and Professor Trevor Beebee and two anonymous reviewers pro-
vided comments and ideas that improved the manuscript. Improvements to the French grammar by
Ivan Ineich and Sylvie Fairless are also greatly appreciated.
REFERENCES
Angilletta M.J., Niewiarowski P.H. & Navas C.A. 2002 – The evolution of thermal physiology in ecto-
therms. J. Therm. Biol., 27: 249-268.
Bailey N.T.J. 1981 – Statistical Methods in Biology. London, English Universities Press, 216 p.
Baker J. 1997 – Stability for Swedish treefrogs? FrogLog, 20: 2-3.
Brattstrom B.H. 1979 – Amphibian temperature regulation studies in the field and laboratory. Am.
Zool., 19: 345-356.
Baumgartner H. 1986 – Amphibia der Schweiz. Zurich, Panda: 1-31.
W.E. & Truebb L. 1986 – Biology of Amphibians. McGraw-Hill, New York, 670 p.
Fog K. 1995 – Amphibian conservation in Denmark. FrogLog, 13: 1-2.
Huey R.B. 1991 – Physiological consequences of habitat selection. Am. Nat., 137: 91-115.
Geise W. & Linsenmair K.E. 1988 – Adaptations of the reed frog Hyperolius viridiflavus (Amphibia,
Anura, Hyperoliidae) to its arid environment. IV. Ecological significance of water economy with com-
ments on thermoregulation and energy allocation. Oecologia, Berlin, 77: 327-338.
John-Alder H.B., Morin P.J. & Lawler, S. 1988 – Thermal physiology, phenology and distribution of
tree frogs. Am. Nat., 132: 506-520.
Knowles T.W. & Weigl P.D. 1990 – Thermal dependence of anuran burst locomotor performance.
Copeia, 1990: 796-802.
Lillywhite H.B., Mittal A.K., Garg T.K. & Das I. 1998 – Basking behavior, sweating and thermal ecol-
ogy of the Indian tree frog, Polypedates maculates. J. Herp., 32: 169-175.
Meek R. 1983 – Body temperatures of two species of desert amphibians Rana perezi and Bufo mauri-
tanicus. Brit. J. Herp., 6: 284-286.
Meek R. & Jolley E. 2006 – Body temperatures of the common toad, Bufo bufo, in the Vendée, France.
Herp. Bull., 95: 21-24.
Navas C.A. 1996 – Metabolic physiology, locomotory performance and thermal niche breadth in neo-
tropical anurans. Physiol. Zool., 69: 1481-1501.
Pellet J. & Schmidt B.R. 2005 – Monitoring distributions using call surveys: estimating site occupancy,
detection probabilities and inferring site absence. Biol. Cons., 123: 223-234.
Pellet J., Rechsteiner L., Skrivervik A.K., Zuercher J.-F. & Perrin N. 2006 – Use of the Harmonic
Direction Finder to study the terrestrial habitats of the European tree frog (Hyla arborea). Amphibia-
Reptilia, 27: 138-142.
Pellet J., Schmidt B.R., Fivaz F., Perrin N. & Grossenbacher K. 2006 – Density, climate and varying
return points: an analysis of long term population fluctuations in the threatened European tree frog.
Oecologia, Berlin, 149: 65-71.
11. - 11 -
Riechert S.E. & Tracy C.R. 1975 – Thermal balance and prey availability – bases for a model relating
web site characteristics to spider reproductive success. Ecology, 56: 265-284.
Shoemaker V.H., Hillman S.S., Hillyard S.D., Jackson D.C., McClanahan L.L., Withers P.C. & Wygoda
M.L. 1992 – Exchange of water, ions and respiratory gases in terrestrial amphibians. In Feder M.E. &
Burggren W.W. (Eds): Environmental Physiology of the Amphibians, p. 125-150. Chicago, University
of Chicago Press, 697 p.
Shoemaker V.H., McClanahan L.L., Withers P.C., Hillman S.S. & Drewe R.C. 1987 – Thermoregula-
tory response to heat in the waterproof frogs Phyllomedusa and Chiromantis. Physiol. Zool., 60: 365-
372.
Snyder G.K. & Hammerson G.A. 1993 – Interrelationships between water economy and thermoregula-
tion in the Canyon tree-frog Hyla arenicolor. J. Arid Environ., 25: 321-329.
Stumpel A.H.P. 1987 – Distribution and present numbers of the tree frog Hyla arborea in Zealand Flan-
ders, the Netherlands. Bijdr. Dierkd., 57: 151-163.
Stumpel A.H.P. 1993 – The terrestrial habitat of Hyla arborea. In Stumpel A.H.P. & Tester U. (Eds):
The Ecology and Conservation of the European tree frog, p. 47-54. Wageningen, Netherlands, Institute
for Forestry and Nature Research.
Tracy C.R. & Christian K.A. 2005 – Preferred temperature correlates with evaporative water loss in
Hylid frogs from Northern Australia. Physiol. Biochem. Zool., 78: 839-846.
Wells K. D. 2007 – The Ecology and Behaviour of Amphibians. Chicago, University of Chicago Press,
1400 p.
Wygoda M.L. & Williams A.A. 1991 – Body temperatures of free-ranging green tree frogs (Hyla
cinerea): a comparison with typical frogs. Herpetologica, 47: 328-335.