Evolutionary and Biomechanical Basis of Drumming Behavior in Woodpeckers

Understanding how and why behavioral traits diversify during the course of evolution is a longstanding goal of organismal biologists. Historically, this topic is examined from an ecological perspective, where behavioral evolution is thought to occur in response to selection pressures that arise through different social and environmental factors. Yet organismal physiology and biomechanics also play a role in this process by defining the types of behavioral traits that are more or less likely to arise. Our paper explores the interplay between ecological, physiological, and mechanical factors that shape the evolution of an elaborate display in woodpeckers called the drum. Individuals produce this behavior by rapidly hammering their bill on trees in their habitat, and it serves as an aggressive signal during territorial encounters. We describe how different components of the display—namely, speed (bill strikes/beats sec–1), length (total number of beats), and rhythm—differentially evolve likely in response to sexual selection by male-male competition, whereas other components of the display appear more evolutionarily static, possibly due to morphological or physiological constraints. We synthesize research related to principles of avian muscle physiology and ecology to guide inferences about the biomechanical basis of woodpecker drumming. Our aim is to introduce the woodpecker as an ideal study system to study the physiological basis of behavioral evolution and how it relates to selection born through different ecological factors.

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Structural plasticity of the avian pectoralis: a case for geometry and the forgotten organelle

Journal of Experimental Biology ◽

10.1242/jeb.234120 ◽

2020 ◽

Vol 223 (23) ◽

pp. jeb234120

Author(s):

Ana Gabriela Jimenez

Keyword(s):

Muscle Fiber ◽

Migratory Birds ◽

Fiber Diameter ◽

Muscular Atrophy ◽

Cost Savings ◽

Reaction Diffusion ◽

Metabolic Cost ◽

Muscle Physiology ◽

Diffusion Limitations ◽

Avian Muscle

ABSTRACTThe avian pectoralis muscle demonstrates incredible plasticity. This muscle is the sole thermogenic organ of small passerine birds, and many temperate small passerines increase pectoralis mass in winter, potentially to increase heat production. Similarly, this organ can double in size prior to migration in migratory birds. In this Commentary, following the August Krogh principle, I argue that the avian pectoralis is the perfect tissue to reveal general features of muscle physiology. For example, in both mammals and birds, skeletal muscle fiber diameter is generally accepted to be within 10–100 µm. This size constraint is assumed to include reaction-diffusion limitations, coupled with metabolic cost savings associated with fiber geometry. However, avian muscle fiber structure has been largely ignored in this field, and the extensive remodeling of the avian pectoralis provides a system with which to investigate this. In addition, fiber diameter has been linked to whole-animal metabolic rates, although this has only been addressed in a handful of bird studies, some of which demonstrate previously unreported levels of plasticity and flexibility. Similarly, myonuclei, which are responsible for protein turnover within the fiber, have been forgotten in the avian literature. The few studies that have addressed myonuclear domain (MND) changes in avian muscle have found rates of change not previously seen in mammals. Both fiber diameter and MND have strong implications for aging rates; most aging mammals demonstrate muscular atrophy (a decrease in fiber diameter) and changes in MND. As I discuss here, these features are likely to differ in birds.

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Are some individuals generally more behaviorally plastic than others? An experiment with sailfin mollies

PeerJ ◽

10.7717/peerj.5454 ◽

2018 ◽

Vol 6 ◽

pp. e5454 ◽

Cited By ~ 4

Author(s):

Julie Gibelli ◽

Nadia Aubin-Horth ◽

Frédérique Dubois

Keyword(s):

Individual Differences ◽

Behavioral Plasticity ◽

Behavioral Responses ◽

Learning Task ◽

Behavioral Traits ◽

Physiological Constraints ◽

Trade Offs ◽

Proximate Factors ◽

Evolutionary Consequences ◽

Sailfin Mollies

Individuals within the same population generally differ among each other not only in their behavioral traits but also in their level of behavioral plasticity (i.e., in their propensity to modify their behavior in response to changing conditions). If the proximate factors underlying individual differences in behavioral plasticity were the same for any measure of plasticity, as commonly assumed, one would expect plasticity to be repeatable across behaviors and contexts. However, this assumption remains largely untested. Here, we conducted an experiment with sailfin mollies (Poecilia latipinna) whose behavioral plasticity was estimated both as the change in their personality traits or mating behavior across a social gradient and using their performance on a reversal-learning task. We found that the correlations between pairwise measures of plasticity were weak and non-significant, thus indicating that the most plastic individuals were not the same in all the tests. This finding might arise because either individuals adjust the magnitude of their behavioral responses depending on the benefits of plasticity, and/or individuals expressing high behavioral plasticity in one context are limited by neural and/or physiological constraints in the amount of plasticity they can express in other contexts. Because the repeatability of behavioral plasticity may have important evolutionary consequences, additional studies are needed to assess the importance of trade-offs between conflicting selection pressures on the maintenance of intra-individual variation in behavioral plasticity.

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Morphological and kinematic basis of the hummingbird flight stroke: scaling of flight muscle transmission ratio

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2011.2238 ◽

2011 ◽

Vol 279 (1735) ◽

pp. 1986-1992 ◽

Cited By ~ 33

Author(s):

Tyson L. Hedrick ◽

Bret W. Tobalske ◽

Ivo G. Ros ◽

Douglas R. Warrick ◽

Andrew A. Biewener

Keyword(s):

Beat Frequency ◽

Transmission Ratio ◽

Muscle Physiology ◽

Avian Flight ◽

Physiological Constraints ◽

Translational Movement ◽

Axis Rotation ◽

Small Muscle ◽

Inversion Mechanism ◽

Stroke Cycle

Hummingbirds (Trochilidae) are widely known for their insect-like flight strokes characterized by high wing beat frequency, small muscle strains and a highly supinated wing orientation during upstroke that allows for lift production in both halves of the stroke cycle. Here, we show that hummingbirds achieve these functional traits within the limits imposed by a vertebrate endoskeleton and muscle physiology by accentuating a wing inversion mechanism found in other birds and using long-axis rotational movement of the humerus. In hummingbirds, long-axis rotation of the humerus creates additional wing translational movement, supplementing that produced by the humeral elevation and depression movements of a typical avian flight stroke. This adaptation increases the wing-to-muscle-transmission ratio, and is emblematic of a widespread scaling trend among flying animals whereby wing-to-muscle-transmission ratio varies inversely with mass, allowing animals of vastly different sizes to accommodate aerodynamic, biomechanical and physiological constraints on muscle-powered flapping flight.

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WHEN NATURAL PHENOMENA ENTER THE SYMBOLIC SPHERE: AN ECOLOGICAL PERSPECTIVE ON RITUAL TEXTS WITHIN THE EGYPTIAN FUNERARY CULT

Numen ◽

10.1163/156852704773558205 ◽

2004 ◽

Vol 51 (1) ◽

pp. 1-19

Author(s):

Erika Meyer-Dietrich

Keyword(s):

Ecological Factors ◽

Ancient Egypt ◽

Ecological Perspective ◽

Natural Phenomenon ◽

Natural Phenomena ◽

New Approach ◽

Religious Ritual ◽

Regular Event ◽

Symbolic Value ◽

Methodological Considerations

AbstractThis article presents a new approach in the study of the ecology of religion. Single ecological factors that appear as subject matter in religious sources are analyzed as factors in the religious world. The symbolic value is applied to environmental factors through ritualization. The natural phenomenon of the inundation of the river Nile was a regular event in ancient Egypt. To investigate the reproduction and use of this ecological factor in religious ritual a model has been developed called "The Dynamic Ecology of Religion." This model and its theoretical and hermeneutical basis are outlined, some methodological considerations are made, and the explanatory value of the model discussed.

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A Narrative Case Study of Chinese Senior High School English Teachers’ Emotions: An Ecological Perspective

Frontiers in Psychology ◽

10.3389/fpsyg.2021.792400 ◽

2021 ◽

Vol 12 ◽

Author(s):

Xiaohui Sun ◽

Liu Yang

Keyword(s):

High School ◽

Emotional Development ◽

Ecological Factors ◽

English Teachers ◽

Senior High School ◽

Ecological Perspective ◽

High School English ◽

Teacher Emotion ◽

Narrative Case Study

Teacher emotion research is of great significance to teachers’ teaching effectiveness, professional development, and physical and mental health. Taken from an ecological perspective, this narrative case study used purposeful sampling to select two Chinese senior high school English teachers as research participants. Various data collection methods were used, including narrative framework, teacher interview and teacher reflection log, to describe the emotional episodes of Chinese senior high school English teachers before and after collective lesson presentation, trial teaching, and formal teaching in a teaching improvement project. The purpose of this collection of data was to explore the dynamic emotional development process and characteristics of Chinese senior high school English teachers in the interaction with ecological systems and those ecological factors that may influence their emotional development. Results indicated that the two participants developed 68 emotions: 39 positive and 29 negative emotions. At exosystem, they developed the most emotions (28 emotions). Teacher emotion changed with time quite obviously. They evolved from positive to negative and, finally, predominantly positive. Personal antecedents, contextual antecedents, and teachers’ emotional capacity are the main ecological factors that may influence the development of teacher emotion. Based on the research findings, implications for teachers’ professional development and teacher education were also provided.

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Put some muscle behind it: Understanding movement capacity of tropical birds

The Auk ◽

10.1093/ornithology/ukaa068 ◽

2021 ◽

Author(s):

W Douglas Robinson ◽

Bryan Rourke ◽

Jeffrey A Stratford

Keyword(s):

Current Knowledge ◽

Critical Evaluation ◽

Bird Species ◽

Landscape Fragmentation ◽

Movement Behavior ◽

Muscle Physiology ◽

Cellular Mechanisms ◽

Avian Flight ◽

Avian Muscle ◽

And Migration

Abstract The capacity for flight varies widely among bird species and influences their ecology, evolution, and conservation. Variation in vagility is influenced by behavioral responses to the nature of gaps between habitat elements as well as intrinsic characteristics of the species, particularly physiological traits influencing the physical capacity for sustained flight. Here, we briefly summarize the current state of knowledge revealing the wide variety of movement capacities of Neotropical birds. We then review current knowledge of avian muscle physiology and the role that muscle characteristics may play in influencing movement behavior. We argue that fundamental shifts in our understanding of avian muscle physiology and the influence of physiology on movement behavior remain to be elucidated, in part because knowledge from other vertebrates is being inappropriately applied to birds. In particular, critical evaluation of assumptions applied to birds from detailed studies of mammals is needed. Moving away from simple binary categorizations of avian flight muscles as “red vs. white” or “fast vs. slow” to characterize the cellular mechanisms and specific isoforms active at various life stages or seasons is also needed. An increasingly large number of avian species with a wide array of flight styles from hummingbirds to soaring raptors are appearing in GenBank, facilitating detailed physiological and evolutionary comparisons among species. Properly assessing the muscle physiological characteristics of Neotropical bird species with a wide array of movement capacities may improve our abilities to predict which species are most sensitive to landscape fragmentation and other factors that influence dispersal and migration.

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How to Psychologically Minimize Scratching Impulses

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000183 ◽

2014 ◽

Vol 222 (3) ◽

pp. 140-147 ◽

Cited By ~ 5

Author(s):

Ariane Sölle ◽

Theresa Bartholomäus ◽

Margitta Worm ◽

Regine Klinger

Keyword(s):

Cognitive Processes ◽

Placebo Effect ◽

Psychological Factors ◽

Pharmacological Treatments ◽

Physiological Basis ◽

Psychological Mechanisms ◽

Physical Complaints ◽

Factors Influencing ◽

The Impact ◽

Placebo Model

Research in recent years, especially in the analgesic field, has intensively studied the placebo effect and its mechanisms. It has been shown that physical complaints can be efficiently reduced via learning and cognitive processes (conditioning and expectancies). However, despite evidence demonstrating a large variety of physiological similarities between pain and itch, the possible transfer of the analgesic placebo model to itch has not yet been widely discussed in research. This review therefore aims at highlighting potential transfers of placebo mechanisms to itch processes by demonstrating the therapeutic issues in pharmacological treatments for pruritus on a physiological basis and by discussing the impact of psychological mechanisms and psychological factors influencing itch sensations.

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