Gordon Burghardt

University of Tennessee at Knoxville | UTK · Departments of Psychology and Ecology & Evolutionary Biology

Jakob von Uexküll developed his core ideas on Umwelt, inner world, counter world, and the functional circle over 100 years ago. While they influenced the early ethologists and phenomenologists, the full import of his ideas were either not recognized or were ignored for various reasons. In the case of ethology, proponents such as Nikolaas Tinbergen...

While elucidating the evolutionary trajectory of green anacondas, we previously documented the existence of two distinct species, Eunectes akayima sp. nov. and Eunectes murinus (Linnaeus, 1758), that separated approximately 10 million years ago. Our research integrates a novel molecular clock approach, focuses on tectonic plate movements with fossi...

Anacondas, genus Eunectes, are a group of aquatic snakes with a wide distribution in South America. The taxonomic status of several species has been uncertain and/or controversial. Using genetic data from four recognized anaconda species across nine countries, this study investigates the phylogenetic relationships within the genus Eunectes. A key f...

For decades, texts on methods in animal behavior research have stressed the need for observers of behavior to work to minimize potential unconscious biases in their coding of data. Two major ways of minimizing these biases are to carry out data coding blind to the key comparisons being made in the study and to have high inter‐observer reliability....

The Beaver Archipelago is a series of islands in northern Lake Michigan, USA, roughly equidistant from the lower and upper peninsulas of the state of Michigan. Of the eight species of snakes found in the archipelago, prey generalist Common Gartersnakes, Thamnophis sirtalis, are by far the most common, inhabiting both the nearby mainland and all the...

BROOKS, H.J.B. & G.M. Burghardt. A comparative review of interspecific social play among nonhuman animals. NEUROSCI BIOBEHAV REV XX(X) XXX-XXX, XXXX.- Few species play socially with another species, hereafter called interspecific social play (ISP). ISP involves reading and responding appropriately to social cues of other species, often taxonomicall...

The polyvagal theory (PT), offered by Porges (2021), proposes that the autonomic nervous system (ANS) was repurposed in mammals, via a second vagal nerve, to suppress defensive strategies and support the expression of sociality. Three critical assumptions of this theory are that (1) the transition of the ANS was associated with the evolution of soc...

Play behavior is a prominent aspect of juvenile behavior for many animals, yet early development, especially play with objects, has received little attention. Our previous study on object play introduced our general methods, focusing on litter differences in the developmental trajectory of object play and toy preferences. Here, we present a detaile...

The polyvagal theory (PT), offered by Porges (2021), proposes that the autonomic nervous system (ANS) was repurposed in mammals, via a "second vagal nerve", to suppress defensive strategies and support the expression of sociality. Three critical assumptions of this theory are that (1) the transition of the ANS was associated with the evolution of '...

Syrian hamsters show complex social play behavior and provide a valuable animal model for delineating the neurobiological mechanisms and functions of social play. In this review, we compare social play behavior of hamsters and rats and underlying neurobiological mechanisms. Juvenile rats play by competing for opportunities to pin one another and at...

Despite abundant evidence to the contrary, non-avian reptiles are widely considered as behavioural and cognitive underachievers. The persistent myth of the sluggish, primitive, stupid reptile can be traced, at least in part, to long-standing misconceptions about reptilian brain size and organisation. Historically, reptile brains have been considere...

The captive environments that we provide for reptiles are not ideal. This issue applies across a variety of situations, including: rearing hatchlings or neonates in captivity prior to release in the field for conservation reintroduction efforts (head-starting); maintaining population in zoological or educational exhibits; operating commercial facil...

Studies exploring the development of object play of wolf pups are lacking. Comparisons of wolves vs. dogs can aid in teasing out the influences of domestication on any differences uncovered between wolves and various dog breeds. We investigated the development of object play from 2 to 9 weeks of age (14–63 days) in 2 litters of hand-reared wolf pup...

This special issue of the International Journal of Play is devoted to the evolution and ontogeny of play and includes papers on various animals, children, and a diversity of phenomena all related to this theme. Papers in the issue provide original data on these species: rheas, Beluga whales, wolves, Japanese monkeys, gorillas, and human children as...

Although self-recognition or self-awareness has been studied with the visually-based mirror test, passed by several species, primarily apes, the possibility of a chemically-based analogue is controversial. Prior studies suggested that chemical self-recognition may occur in some squamate reptiles. To evaluate this possibility, we studied 24 individu...

Comparative psychology, and particularly the Journal of Comparative Psychology, has been criticized for a lack of taxon diversity. The nature and consequences of the critiques are discussed and assessed by analyzing the representation of nonavian reptiles in the journal over its 100-year existence. Although reptiles are indeed rare in the journal,...

Denning behavior has long remained the least observed aspect of bear behavior. During 2010–2013, we used webcams, microphones, the internet, and 14,602 h of archived video to document the denning behaviors of two adult wild black bears (Ursus americanus) as they gave birth and cared for four litters through six winters in northeastern Minnesota. Ob...

An appreciation of the diverse roots of animal behaviour study is essential for informed teaching and stimulating current research and scholarship. Insights by early seminal authors are often ignored, insights that may have avoided subsequent controversies or spawned productive research. Even with internet access now available for much early work,...

Although issues of motivation, including appetitive searching behavior, have been crucial aspects of behavior systems approaches since their inception, as well as in the ethological research and models that inspired them, emotions and affect have been noticeably absent in such analyses. Emotions and affect may have been lying below the surface all...

Play is an important and understudied class of phenomena that likely serves a critical role in the ontogeny and maintenance of fitness-enhancing behaviors. Many species exhibit little or no play. Among those animals that do play, some exhibit only very simple forms, while others engage in complex play both solitarily and socially. Likewise, some an...

In several rodent species social play appears to be necessary for proper deployment of species-specific patterns of aggressive and reproductive behavior. Specifically, in male Syrian hamsters (Mesocricetus auratus), play has been linked to the development of adult aggression. We quantified several types of social play behavior in same-sex peer grou...

Scientific Foundations of Zoos and Aquariums - edited by Allison B. Kaufman January 2019

Wallace Craig’s “Appetites and Aversions as Constituents of Instincts,” one of the seminal articles in animal behavior, comparative psychology, and ethology, appeared 100 years ago this year. The influence of this classic article is continuing and perhaps even expanding. Here we review the major ideas Craig offered in the article, provide a brief s...

Cambridge Core - Educational Psychology - The Cambridge Handbook of Play - edited by Peter K. Smith

Juvenile animals of many species engage in social play, but its functional significance is not well understood. This is especially true for a type of social play called fair play (Fp). Social play often involves behavioral patterns similar to adult behaviors (e.g., fighting, mating, and predatory activities), but young animals often engage in Fp be...

The origins of religion and ritual in humans have been the focus of centuries of thought in archaeology, anthropology, theology, evolutionary psychology and more. Play and ritual have many aspects in common, and ritual is a key component of the early cult practices that underlie the religious systems of societies in all parts of the world. This boo...

Despite the taxonomic, behavioral, and lifestyle diversity among reptile species, behavioral consistency in reptiles has not been examined to the extent that it has been in fish, birds, and mammals. Careful use of terms such as individuality, temperament, personality, and behavioral syndromes is needed as they carry overlapping connotations and var...

Animals that depend on defensive chemicals acquired from food may face a decision when attempting to deter predatory attacks: Should they exhibit antipredator behavior that relies on the toxicity of the sequestered chemicals or should they adopt other behaviors that can avoid predation without using the chemical defense, such as flight? Thus, it is...

The causes and consequences of among-individual variation and covariation in behaviours are of substantial interest to behavioural ecology, but the proximate mechanisms underpinning this (co) variation are still unclear. Previous research suggests metabolic rate as a potential proximate mechanism to explain behavioural covariation. We measured the...

Play and ritual, as usually defined, seem to be disparate phenomena, one focused on freedom and flexibility, the other on formality and rigidity. In actuality, they have many common elements, and these will be explored from a comparative perspective grounded in ethology, evolution and play theory. The description and recognition of play in diverse...

Cuticle melanism in insects is linked to a number of life history traits: a positive relationship is hypothesized between melanism, immune function, fecundity and lifespan. However, it is not clear how activation of the immune system affects trade-offs between life history traits in female mealworm beetles (Tenebrio molitor) differing in cuticle me...

Factors such as temperature, habitat, larval density, food availability and food quality substantially affect organismal development. In addition, risk of predation has a complex impact on the behavioural and morphological life history responses of prey. Responses to predation risk seem to be mediated by physiological stress, which is an adaptation...

Drosophila body characteristics and negative geotaxis under spider predation Data on dry body mass, lipid amount, nitrogen & carbon concentrations and climbing speed during negative geotaxis trials in Drosophila fruit flies (males, females) reared with spiders (predator identity) and in the control group (reared without predators).

The Green Iguana (Iguana iguana) may be the most studied of all Neotropical squamate species. Given that many populations are over-exploited, and other introduced populations represent problems for native species, it is surprising that so few of the publications on the species have had a demographic focus. Here we resurrect data that formed the bas...

Object play occurs in diverse animals in addition to birds and mammals. Although many carnivores engage in object play in a predatory context, many non-predators do so also. Conjectures over the years on the motivation to play are reviewed dealing with intrinsic, developmental, and stimulus factors. We then report on quantitative studies of the pla...

Our knowledge of the biology of neonatal snakes has lagged behind that of adult animals, mostly due to the difficulty of finding and studying neonatal snakes in the wild. Traditional approaches view neonatal reptiles as miniature replicates of their adult counterparts. In this contribution, we present data on the natural history of neonatal Green A...

Social play is a fundamental aspect of behavioral development in many species. Social play deprivation in rats alters dendritic morphology in the ventromedial prefrontal cortex (vmPFC) and we have shown that this brain region regulates responses to social defeat stress in Syrian hamsters. In this study, we tested whether play deprivation during the...

The possible role of play in creativity and innovation in animals is explored. After discussing issues involved in key terms and some prior studies on the creative process in humans, difficult issues in applying them to nonhuman animals are analyzed. If creativity in animals is only to be considered if it can definitely be linked to speciation or t...

Although play occurs in a wide variety of animals, models of the origins of play behavior are lacking. We propose a novel computational model exploring the evolution of non-social frivolous play. Asexually reproducing semelparous animals can either rest or forage. Foraging occurs when an organism is below an energy threshold. Success is determined...

What factors in animal life history facilitate or reduce the probability that a species will perform play behavior? While some relationships are known within species and across individuals, it is not obvious that such relationships can be used to explain differences and similarities in amount and type of play across large taxonomic groupings of ani...

Why animals play has been a perennial question, but most of the thinking about this has been framed in terms of its fitness benefits. A review of our present knowledge about the comparative distribution of play suggests that such an approach that leads to claims that the ‘‘adaptive value of play is’’ are misplaced. Play is relatively rare in the An...

Casualties and impediments inflicted on consumers by defended prey, and vice versa, may be averted by vocalizations, postures, coloration, scents, and other warning, or so-called aposematic, displays. The existence of aposematic signals has challenged biologists who have sought plausible mechanisms for their evolution. Here, we elaborate on the rat...

Reviews the book, Animal Madness: How Anxious Dogs, Compulsive Parrots, and Elephants in Recovery Help Us Understand Ourselves by Laurel Braitman (see record 2014-20916-000 ). Because to most people psychology is centered on studying mental disorders, this book may connect with the public by its wide-ranging take on the mental disorders found in ot...

In this quick guide, Gordon Burghardt considers the criteria for ascribing a particular animal behavior as "play", and in particular the evidence for play in fishes, frogs and reptiles. Copyright © 2015 Elsevier Ltd. All rights reserved.

Whether play occurs in fishes has long been a contentious issue, but recent observations document that social, object, and locomotor play can all be found in some species of teleosts. However, quantitative studies and those documenting individual differences are rare. We recorded hundreds of occurrences of an unusual behavior in three male Tropheus...

As astutely noted by the authors of this provocative article, it is time for evolutionary psychology (EP) to be incorporated into clinical and educational interventions. However, two issues from this article are raised in the current commentary: some historical misconceptions of the evolutionary label and a lack of clear and specific guidelines for...

Cephalopods are generally regarded as the most intelligent group among the invertebrates. Despite their popularity, relatively little is known about the range and function of their cognitive abilities. This book fills that gap, accentuating the varied and fascinating aspects of cognition across the group. Starting with the brain, learning and memor...

Play has long been considered an enigmatic behavior that is hard to define, but having many putative functions difficult to confirm. This situation is changing quite rapidly in recent years. This introduction to a special issue on play provides some general background, historical and contemporary, on the recognition and phylogenetic aspects of play...

Bears are often considered ecological equivalents of large primates, but the latter often respond with fear, avoidance, and alarm calls to snakes, both venomous and non-venomous, there is sparse information on how bears respond to snakes. We videotaped or directly observed natural encounters between black bears (Ursus americanus) and snakes. Inside...

We very much value the integrative formulation of the neural basis of the seeking system put forth by Wright & Panksepp, but we have several concerns that might be incorporated or acknowledged in future versions. These revolve around the need for a more rigorous and modern evolutionary backdrop, a greater appreciation for earlier discussions of app...

Reviews the book, Animal Wise: The Thoughts and Emotions of Our Fellow Creatures by Virginia Morell (see record 2013-12224-000 ). Morell mastered many key elements of the history of the study of animal behavior and mentality. In the introduction she blends the historical medicine with engaging anecdotes involving her pets and sets us up for her tou...

On the third day of life, four groups of eight chicks each were given either rape or canary seed, exclusively. The following day the chicks were given the seed they had not experienced the day previously. For eight days subsequently, the chicks were offered both seeds and the proportion by weight of each seed eaten was determined. Chicks initially...

Two groups of hatchling snapping turtles, without prior feeding experience, were given a meal of either meat or worms. One week later each group was fed the food it had not experienced earlier. The following week each turtle was tested for its preference between the two foods. The two groups of turtles differed significantly in the direction of pre...

Van de Vliert proposes a comprehensive explanation for differences in "freedoms" in diverse human populations based on climate and monetary resources. This intriguing approach, though derived from an evolutionary view covering all species, is based exclusively on human populations. This anthropocentric lens is challenged by ways of testing Van de V...

The relationship between grip strength, book load, and observed book-carrying mode of male and female college students was studied in a natural setting utilizing 350 subjects. It was found that male and female book-carrying modes were significantly different, but that book weights carried by the two sexes did not differ significantly. Male and fema...

Reptiles and amphibians have been neglected in research on cognition, emotions, sociality, need for enriched and stimulating environments, and other topics that have been greatly emphasized in work on mammals and birds. This is also evident in the historic lack of enriching captive environments to reduce boredom and encourage natural behavior and p...

What is the nature of comparative psychology and how does or should it relate to evolutionary psychology? This is a time of reassessment of both fields and this article reviews the history of comparative psychology and its relationships with evolutionary psychology, ethology, and other approaches to behavior from the perspective of a former editor...

Species that sequester toxins from prey for their own defense against predators may exhibit population-level variation in their chemical arsenal that reflects the availability of chemically defended prey in their habitat. Rhabdophis tigrinus is an Asian snake that possesses defensive glands in the skin of its neck ('nuchal glands'), which typically...

Social learning is considered one of the hallmarks of cognition. Observers learn from demonstrators that a particular behavior pattern leads to a specific consequence or outcome, which may be either positive or negative. In the last few years, social learning has been studied in a variety of taxa including birds and bony fish. To date, there are fe...

Although social behavior in vertebrates spans a continuum from solitary to highly social, taxa are often dichotomized as either ‘social’ or ‘non-social’. We argue that this social dichotomy is overly simplistic, neglects the diversity of vertebrate social systems, impedes our understanding of the evolution of social behavior, and perpetuates the er...

In recent years genotyping analysis using mini-and microsatellite markers has provided robust DNA-based support for facultative parthenogenesis (FP) in several lineages of squamate reptiles (snakes and lizards) and sharks. Rather than incidental cases of reproductive error, there is growing evidence that FP is an alternative reproductive strategy a...

Striped crayfish snakes (Regina alleni) undergo a dietary shift from dragonfly larvae to crayfish during ontogeny. Godley (1980) suggested that this shift is attributable to crayfish availability rather than an initial preference for dragonfly larvae. We experimentally tested this hypothesis by measuring the chemosensory response of newborn snakes...

Chemical defenses are widespread among animals, and the compounds involved may be either synthesized from nontoxic precursors or sequestered from an environmental source. Defensive sequestration has been studied extensively among invertebrates, but relatively few examples have been documented among vertebrates. Nonetheless, the number of described...

Distinguishing between hybrid zones formed by secondary contact versus parapatric divergence-with-gene-flow is an important challenge for understanding the interplay of geographic isolation and local adaptation in the origin of species. Similarly, distinguishing between natural hybrid zones and those that formed as a consequence of recent human act...

This commentary acknowledges the fine contribution Palmer makes to distinguishing between the contextualist and consequentialist approaches to understanding human obligations to suffering in animals in 'natural' settings, and uses her examples to reflect on larger issues in evaluating how our species treats and responds to nature. Overall, this gen...

Since the 1970s, texts on research methods in animal behavior advocate that researchers minimize potential observer bias in their studies. One way to minimize possible bias is to record or score behavioral data blind to treatment, group, or individual. Another way to reduce bias is for researchers to analyze subsets or entire sets of data independe...

Long-lived species are expected to have long-term memory capabilities. In this study we tested nine Florida Red-bellied Cooters (Pseudemys nelsoni) on their retention for both a procedural food acquisition task and visual discrimination task learned in a previous experiment. The turtles were tested and retrained after two months, after another 7.5...

Some comments are appended to Patrick Bateson’s reflections on the future of behavioral biology that were triggered by remembering the contributions of Günter Tembrock to ethology. While the suggestions made are valid and insightful, a few specific areas where exciting research possibilities may reside are added including those involving communicat...

Characterizing behavior in any organism as play, including in humans, has often been controversial. Intuitive understandings of what constitutes 'play' are often difficult to describe in words so that other researchers can use them. This leads to problems in comparing studies, formulating and testing research hypotheses, and even in having a shared...

In the socially polymorphic spider Anelosimus studiosus, males mature early in the reproductive season and recruit to the webs of juvenile females and guard them until they mature. During the period before females mature, males and females engage in repeated bouts of non-conceptive (play) sexual behavior, where the pair courts and engages in mock c...

Rhabdophis tigrinus is an Asian natricine snake that possesses unusual defensive glands on the dorsal surface of its neck. These nuchal glands typically contain cardiotonic steroidal toxins known as bufadienolides, which are also abundant in the skin of toads. Feeding experiments demonstrated that toads consumed as prey are the ultimate sources of...

Of the various chemical defensive adaptations of vertebrates, nuchal glands are among the most unusual. First described in a Japanese natricine snake, Rhabdophis tigrinus, in 1935, these organs are embedded under the skin of the neck region as a series of paired glands that have neither lumina nor ducts. The major chemical components of the glandul...

Until recently, facultative automictic parthenogenesis within the squamate reptiles exhibiting ZZ:ZW genetic sex determination has resulted in single reproductive events producing male (ZZ) or female (ZW) offspring. With the recent discovery of viable parthenogenetically produced female (WW) Boa constrictors, the existence of further parthenogeneti...

We investigated whether turtles (Pseudemys nelsoni) could learn about a visual object cue to obtain food reinforcement by observing conspecifics that had learned the task. This study was designed with a three part task which, if completed by the observer turtles, would provide evidence of their abilities to learn from other turtles using stimulus e...

The ability to detect and respond to potential predators is key for the survival of individuals, but this ability is sometimes lost via relaxation of antipredator behavior when prey species are separated from predators. Adult and predator-naïve neonate gartersnakes (Thamnophis sirtalis) from mainland and insular sites where they do and do not occur...