Evolution Commons^™

Learning, Memory, Cognition, And The Question Of Sentience In Fish, Robert Gerlai

Animal Sentience

Evolutionarily conserved features have been demonstrated at many levels of biological organization across a variety of species. Evolutionary conservation may apply to complex behavioral phenomena too. It is thus not inconceivable that a form of sentience does exist even in the lowest order vertebrate taxon, the teleosts. How similar it is to human sentience in its level of complexity or in its multidimensional features is a difficult question, especially from an experimental standpoint, given that even the definition of human sentience is debated. Woodruff attempts a Turing-like test of fish sentience, and lists numerous neuroanatomic, neurophysiological and behavioral similarities between …

Mental Representations Are Not Necessary For Fish Consciousness, Luis H. Favela

Animal Sentience

Woodruff (2017) argues that teleost fishes are capable of phenomenal consciousness. Central to his argument is the assumption that phenomenal consciousness is representational in nature. I think the commitment to a representational theory of consciousness undermines Woodruff’s case for teleost phenomenal consciousness. The reason is that organisms do not need to perceive the world indirectly via mental images/representations in order to have phenomenological experiences. My argument is based on considerations of ecological psychology and comparative ethology.

Animal Models, Agendas And Sentience, Thomas Creson

Animal Sentience

Woodruff’s target article on teleost consciousness is a well-organized logical argument for considering the fish as a sentient being. This becomes more important for animal ethical discussion as the fish becomes a more important and legitimate animal model for investigating animal states and traits associated with higher levels of behavior such as learning and memory.

The Emotional Brain Of Fish, Sonia Rey Planellas

Animal Sentience

Woodruff (2017) analyzes structural homologies and functional equivalences between the brains of mammals and fish to understand where sentience and social cognition might reside in teleosts. He compares neuroanatomical, neurophysiological and behavioural correlates. I discuss current advances in the study of fish cognitive abilities and emotions, and advocate an evolutionary approach to the underlying basis of sentience in teleosts.

We Still Need A Theory, Paula Droege

Animal Sentience

Woodruff (2017) has compiled a convincing array of data to support his contention that teleost fish feel pain. However, in the absence of an explanatory theory about the nature and function of consciousness, a checklist of criteria is insufficient to allay skeptical concerns. I offer a theory that can explain why features like selective attention and behavioral flexibility indicate consciousness. Consciousness represents the present moment in order to allow dynamic changes in actions or goals in response to situational demands.

Similar Anatomy Does Not Imply Comparable Function, Jay R. Stauffer Jr.

Animal Sentience

Woodruff concludes that ray-finned fishes (Actinopterygii) are sentient and that the pallium contributes to sentience in these fishes. He gives a detailed description of the pallium; however, he assumes that similar structures in fishes and tetrapods support similar behaviors, capabilities, and functions. I reject the premise that similarities in structure imply similarities in function. The fact that a selected species of fish may exhibit behaviors, reactions, and/or anatomy suggestive of sentience does not necessarily generalize to all teleosts.

Can Unconscious Brain Processes Indicate Sentience?, Vincent Taschereau-Dumouchel, Piercesare Grimaldi, Hakwan Lau

Animal Sentience

We disagree with Woodruff that we have good neurobiological reasons to think fishes are sentient, because mechanisms for consciousness are controversial even in humans. To the extent that there are consensuses in that literature, they do not support Woodruff's claims.

Fish Are Flexible Learners Who Can Discriminate Human Faces, Ulrike E. Siebeck

Animal Sentience

In his book “What a fish knows” Jonathan Balcombe (2016a, b) has created a comprehensive profile of a group of animals still often thought to have a 3-second memory, no ability to feel pain, and a generally limited ability to learn. Chapter by chapter, Balcombe dismantles these and other such assumptions and makes a convincing case that fish have many abilities that are not that different from our own. Here, I focus on one example which supports the notion that fish are flexible learners and able to perform tasks which are generally thought to require the advanced processing power of …

To Identify All The Relevant Factors Is To Explain Feeling, Arthur S. Reber

Animal Sentience

Several additional comments on Reber (2016a) have appeared. Like those addressed in Reber (2016b), they reflect points of agreement and disagreement on various elements of my Cellular Basis of Consciousness (CBC) model. Some, however, seem to have missed key points. I'm willing to take some responsibility for this. Perhaps I was not clear about some of the more radical points of the model. Hopefully the case-by-case review here will help.

Consciousness Is Not Inherent In But Emergent From Life, Jon Mallatt, Todd E. Feinberg

Animal Sentience

Reber’s theory of the cellular basis of consciousness (CBC) is right to emphasize that we should study consciousness (sentience) in its simplest form, taking its evolution into account. However, not enough evidence is presented to support CBC’s unorthodox claim that even simple, one-celled organisms are conscious. As pointed out by other commentators, the CBC seems to be based on outdated ideas about evolution and does not acknowledge that consciousness could be an evolutionary novel feature. Such emergent features are abundant in living organisms. We review our own emergentist solution, in which consciousness evolved in the elaborating nervous systems of the …

What Can Research On Nonhumans Tell Us About Human Dissonance?, Jennifer Vonk

Animal Sentience

Zentall’s thoughtful review of the literature on cognitive dissonance in nonhumans helps to highlight the common finding that similar outcomes in humans and nonhumans can be attributed to different underlying mechanisms. I advocate a more fully comparative approach to the underlying mechanisms, avoiding the assumption of shared processes in humans and nonhumans.

Establishing That Contrast Is Cognitive Dissonance, Travis R. Smith

Animal Sentience

Zentall suggests that the same mechanism underlies cognitive dissonance in humans and the within-trial contrast effect in pigeons (and humans). The contrast effect has face validity in explaining cognitive dissonance, but more research is needed to establish construct validity. To determine whether both phenomena share the same mechanism, future research should test (1) whether both share physiological processes, (2) whether individuals who show sensitivity to one are also sensitive to the other, and (3) whether both phenomena are affected by the same changes in an independent variable.

Raising The Moral Consciousness Of Science, Bernard Rollin

Animal Sentience

Precaution on behalf of sentient animals should not be tempered by the questionable principle of the amorality of science.

The Precautionary Principle: A Cautionary Note, Robert C. Jones

Animal Sentience

The precautionary principle regarding animal sentience is often used in decision-making about human actions that may cause harm to nonhuman animals. Birch (2017) develops an account of the precautionary principle requiring two pragmatic rules for its implementation. I support Birch's proposal but offer a cautionary note about relying on precautionary principles if one's ultimate goal is to emancipate animals from human domination.

Will The Precautionary Principle Broaden Acceptance Of Animal Sentience?, Simon Leadbeater

Animal Sentience

Birch uses existing practice to develop a formal Animal Sentience Precautionary Principle (ASPP), which he hopes will become more widely adopted and improve animal welfare outcomes. Birch considers the assumption that all animals are sentient to be extreme. Despite its merits, Birch’s ASPP remains human-centred.

Assessing Negative And Positive Evidence For Animal Pain, Robert W. Elwood

Animal Sentience

Jonathan Birch suggests that we should take one well-conducted study that produces results consistent with the idea of pain as being sufficient to invoke the animal sentience precautionary principle. Here, I consider how to balance negative and positive results from such studies using examples from my own work. I also consider which criteria of pain might provide strong inference about pain and which may prove to be weaker.

Operationalizing Fear Through Understanding Vigilance, Ralph Adolphs

Animal Sentience

Beauchamp’s target article raises important questions about the features that often accompany fear. How reliable an indicator of fear is vigilance? Is it constitutive, cause, or consequence of fear? These questions force us towards a clearer definition of “fear.”

Fear And Loathing On The Landscape: What Can Foraging Theory Tell Us About Vigilance And Fear?, Burt P. Kotler, Joel S. Brown

Animal Sentience

We discuss fear and vigilance from the perspective of foraging theory. Rather than focusing on proximate indicators of fear, we suggest that fear is an adaptation for assigning a cost to activities that incur a risk of injury or death. We use theory to provide definitions for fear and vigilance and then use that theory to compare them. We agree that there are limits to the reliability of vigilance as an indicator of fear, but we arrive at this conclusion differently.

Methodological Suggestions For Inferring Fear From Vigilance, Julie A. Teichroeb

Animal Sentience

I suggest some methods for data-collection and analysis that may help researchers infer fear from vigilance.

Evolution Of Molt Phenology In Dwarf Hamsters, Zachary Clare-Salzler

Graduate Student Theses, Dissertations, & Professional Papers

Environmental seasonality presents many challenges for survival. In response, organisms from across the tree of life exhibit adaptive phenology, which can facilitate survival from season to season. In particular, many species are white in the winter and brown in the summer where winter snow cover alters the visual environment. There is an extensive body of literature describing the physiological and cellular regulation of this trait in the Siberian dwarf hamster (Phodopus sungorus), but there are major shortcomings in our understanding concerning the evolution and molecular regulation of mammalian skin phenology. Notably, little is known about the genetic basis …

Contributions Of Gene Copy Number Variation To Genome Evolution And Local Adaptation Of The Cyanobacterium Acaryochloris, Amy L. Gallagher

Graduate Student Theses, Dissertations, & Professional Papers

Acaryochloris is a recently discovered genus of cyanobacteria, unique in its use of an uncommon chlorophyll as its major photosynthetic pigment, and in its peculiar genome dynamics. Members of this genus exhibit increased genic copy number variation (CNV), which is thought to be primarily derived from gene duplications and horizontal gene transfer (HGT). Acaryochloris provides an ideal system to explore mechanisms behind maintenance of gene duplicates and the influence of CNV in local adaptation. Here, I propose a mechanism for retention of gene duplicates of the bacterial recombinase, RecA, in Acaryochloris genomes and provide preliminary evidence that these paralogs are …

Neutral And Adaptive Genetic Variation In North American Hardwood Tree Species, Sudhir Khodwekar

Dissertations, Master's Theses and Master's Reports

'Northern Hardwoods,’ are a characteristic composition of multiple tree species and a part of the rich and diverse northeastern forests. Hardwoods e.g. oaks (Quercus: Fagaceae and Sugar maple), serve as foundation species and offer ecological and economical gains to wildlife and humans. Most of the forest trees go through many biotic and abiotic stresses, for example climate change in their long life span. To overcome these threats and to adapt to changing conditions, tree species need to maintain variation especially in adaptive genes. Therefore, it is necessary to analyze genetic diversity within forest tree populations and take appropriate …

Evolution In The Deep Sea: Scales And Mechanisms Of Population Divergence, Amanda E. Glazier

Graduate Doctoral Dissertations

The deep sea is the Earth’s largest ecosystem and harbors a unique and largely endemic fauna. Although most research has focused on the ecological mechanisms that allow coexistence, recent studies have begun to investigate how this remarkable fauna evolved.. My work quantifies geographic patterns of genetic variation and investigates potential mechanisms that shape evolution in the deep ocean.

Bathymetric genetic divergence is common in the deep sea with population structure typically decreasing with depth. The evolutionary mechanisms that underlie these patterns are poorly understood. Geographic patterns of genetic variation indicated that the protobranch bivalve Neilonella salicensis was composed of two …

Reef Society And The Tyranny Of Data, Robert Wintner

Animal Sentience

Modern science now approaches divergent processes in many areas, including health assessments of marine eco-systems and social aspects of marine species. Scientific data have long enjoyed a reputation for objectivity but incidents of science-for-hire, data spinning/skewing and political jading are more frequent than ever. In the field of reef creature sensitivity, technical treatises can “logically” explain away what a person of average education can clearly observe on any given reef. Western medicine discounted anecdotal evidence of any cure outside the 4% margin of error until those cures demanded attention and in some cases application. Modern science must now enter an …

Still Wondering How Flesh Can Feel, Gwen J. Broude

Animal Sentience

Reber believes he has simplified Chalmers’s “hard problem” of consciousness by arguing that subjectivity is an inherent feature of biological forms. His argument rests on the related notions of continuity of mind and gradual accretion of capacities across evolutionary time. These notions need to be defended, not just asserted. Because Reber minimizes the differences in mental faculties among species across evolutionary time, it becomes easier to assert, and perhaps believe, that sentience is already present in early biological forms. The more explicit we are about the differences among these mental faculties and the differences across species, the less persuasive is …

Phylogenetics, Biogeography, And Climate Niche Variation Of South Pacific And Hawaiian Psychotria, Elaine Zhang

Master's Theses

Why do some species have broad geographic distributions, while other species are confined to a narrow distribution? Species age, ecological niche, or dispersal traits may help explain why some insular species are abundant and found on many islands, while others are rare and restricted to one island. In this study, I inferred a robust, time-calibrated phylogeny of the Hawaiian Psychotria, using two nuclear and eight chloroplast loci, sampling 67 individuals. I coupled my phylogenetic hypothesis with climatic data, ecological niche modeling, and morphological dispersal characteristics to explain the variation in number of islands occupied by each species. My inferred phylogeny …

Changes In Male Hunting Returns, Raymond B. Hames

Department of Anthropology: Faculty Publications

Research on changes in male hunting among hunter-gatherers addresses two important issues in early human evolution: the nature of the family and trade-offs in mating and parenting effort as well as the development of embodied capital. In the hunter-gatherer literature, there is a debate about the function of male hunting that has implications for understanding the role males play in the evolution of the pair bond. The traditional model argues that male hunting and other economic activities are forms of male provisioning or parenting effort designed to enhance a man’s fitness through his wife’s reproduction and the survivorship of their …

Review Of Northwestern African Buthacus, With Description Of Buthacus Stockmanni Sp. N. From Morocco And Western Sahara (Scorpiones, Buthidae), František Kovařík, Graeme Lowe, František Šťáhlavský

Euscorpius

Northwestern African Buthacus species are revised. Buthacus stockmanni sp. n. from Morocco and Western Sahara is described and fully complemented with color photos of live and preserved specimens, as well as their habitat. The hemispermatophore of B. stockmanni sp. n. is illustrated and described. In addition to morphology and hemi-spermatophores, we also describe the karyotypes of B. stockmanni sp. n. (2n=20). B. stockmanni sp. n. is compared with B. occidentalis Vachon, 1953 and B. ziegleri Lourenço, 2000. Both these species are differentiated from B. stockmanni sp. n. geographically and morphologically. The male of B. stockmanni sp. n. has fingers of …

First Report Of Lissothus Occidentalis Vachon, 1950 (Scorpiones: Buthidae) From Morocco And Western Sahara, With Notes On Ecology And Captive Breeding, Mark Stockmann, Carlos Turiel, Felix Althoff, Graeme Lowe, František Kovařík

Euscorpius

Genus Lissothus Vachon, 1948 represented by L. occidentalis Vachon, 1950 is reported for the first time from four localities in Morocco and the Western Sahara. We provide a revised diagnosis of L. occidentalis, fully complemented with color photos of live and preserved specimens. Hemispermatophore is also illustrated and described in detail. Furthermore, we describe aspects of the ecology of this species, and provide photos of collection sites and habitats. We also report on the reproductive biology of this species based on captive breeding and rearing. and provide the first envenomation report for the species.

Animals Aren’T Persons, But Is It Time For A Neologism?, Helen Steward

Animal Sentience

Mark Rowlands argues that at least some animals are persons, based on the idea that (i) many animals have a property he calls “pre-reflective awareness,” (ii) the capacity for pre-reflective awareness is sufficient to satisfy the traditional Lockean definition of personhood, and (iii) satisfaction of the traditional Lockean definition of personhood is sufficient for being a person. I agree with (i) and can see that there is a persuasive case for (ii), but I think the case against (iii) blocks the conclusion that animals are persons. I suggest that we may need instead to coin a neologism in order to …