Zoology Commons^™

Should Fish Feel Pain? A Plant Perspective, František Baluška

Animal Sentience

Key (2016) claims fish that fish do not feel pain because they lack the necessary neuronal architecture: their responses to noxious stimuli, according to Key, are executed automatically without any feelings. However, as pointed out by many of his commentators, this conclusion is not convincing. Plants might provide some clues. Plants are not usually thought to be very active behaviorally, but the evidence suggests otherwise. Moreover, in stressful situations, plants produce numerous chemicals that have painkilling and anesthetic properties. Finally, plants, when treated with anesthetics, cannot execute active behaviors such as touch-induced leaf movements or rapid trap closures after localizing …

A Single Strand Of Argument With Unfounded Conclusion, Robert W. Elwood

Animal Sentience

Key (2016) describes the neural system involved in human pain experience in an excellent fashion but then suggests that only that complete system can generate the experience of pain. Thus animals without all components will not feel pain. This argument has been refuted in the past by analogy to vision where it is clear that a broad range of taxa, vertebrate and invertebrate, have good visual abilities albeit with completely different central nervous systems and receptors. This known counterargument to Key’s main idea is not mentioned in the target article. Further criteria that might indicate pain and studies examining these …

What Would The Babel Fish Say?, Monica Gagliano

Animal Sentience

Starting with its title, Key’s (2016) target article advocates the view that fish do not feel pain. The author describes the neuroanatomical, physiological and behavioural conditions involved in the experience of pain in humans and rodents and confidently applies analogical arguments as though they were established facts in support of the negative conclusion about the inability of fish to feel pain. The logical reasoning, unfortunately, becomes somewhat incoherent, with the arbitrary application of the designated human criteria for an analogical argument to one animal species (e.g., rodents) but not another (fish). Research findings are reported selectively, and questionable interpretations are …

Pain And Fish Welfare, Eliane Gonçalves-De-Freitas

Animal Sentience

The evolutionary approach of Key’s (2016) target article, generically comparing humans with fish of all kinds, is simplistic. The author ignores published research on structural and molecular aspects of pain in fish. The target article reads more like a selective polemic against fish welfare than an even-handed analysis.

Brain Processes For “Good” And “Bad” Feelings: How Far Back In Evolution?, Jaak Panksepp

Animal Sentience

The question of whether fish can experience pain or any other feelings can only be resolved by neurobiologically targeted experiments. This commentary summarizes why this is essential for resolving scientific debates about consciousness in other animals, and offers specific experiments that need to be done: (i) those that evaluate the rewarding and punishing effects of specific brain regions and systems (for instance, with deep-brain stimulation); (ii) those that evaluate the capacity of animals to regulate their affective states; and (iii) those that have direct implications for human affective feelings, with specific predictions — for instance, the development of new treatments …

Pain In Fish: Weighing The Evidence, James D. Rose

Animal Sentience

The target article by Key (2016) examines whether fish have brain structures capable of mediating pain perception and consciousness, functions known to depend on the neocortex in humans. He concludes, as others have concluded (Rose 2002, 2007; Rose et al. 2014), that such functions are impossible for fish brains. This conclusion has been met with hypothetical assertions by others to the effect that functions of pain and consciousness may well be possible through unknown alternate neural processes. Key's argument would be bolstered by consideration of other neurological as well as behavioral evidence, which shows that sharks and ray are fishes …

Why Is Fish “Feeling” Pain Controversial?, E. Don Stevens

Animal Sentience

In his excellent target article, Key (2016) develops a mechanistic argument in an attempt to show why it is unlikely that fish can “feel” pain or for that matter, “feel” anything. The topic is controversial and likely to achieve the goal of getting many hits for the inaugural issue of the new journal, Animal Sentience. In my view, the question is unlikely to be answered, for two reasons. First, because the proponents of the “fish feel pain” controversy are untrained and unskilled in the details and jargon of neurophysiology and/or neuroanatomy, and the opponents of the controversy, like Key, …

Animal Sentience: The Other-Minds Problem, Stevan Harnad

Animal Sentience

The only feelings we can feel are our own. When it comes to the feelings of others, we can only infer them, based on their behavior — unless they tell us. This is the “other-minds problem.” Within our own species, thanks to language, this problem arises only for states in which people cannot speak (infancy, aphasia, sleep, anaesthesia, coma). Our species also has a uniquely powerful empathic or “mind-reading” capacity: We can (sometimes) perceive from the behavior of others when they are in states like our own. Our inferences have also been systematized and operationalized in biobehavioral science …

What’S The Common Sense Of Just Some Improvement Of Some Welfare For Some Animals?, Liv Baker

Animal Sentience

The goal of Animal Welfare Science to reduce animal suffering is commendable but too modest: Suffering animals need and deserve far more.

End-State Welfarism, Joel Marks

Animal Sentience

Yew-Kwang Ng’s research is the work of an obviously sincere, intelligent, and conscientious animal advocate. But I am unable to accept his starting assumption that animal welfare is an appropriate basis for animal ethics. More specifically I argue that animal welfare as a means to animal liberation is an issue that can be debated, but animal welfare as the ultimate end or goal of animal advocacy is misguided.

Going Beyond Just-So Stories, Brian Key

Animal Sentience

Colloquial arguments for fish feeling pain are deeply rooted in anthropometric tendencies that confuse escape responses to noxious stimuli with evidence for consciousness. More developed arguments often rely on just-so stories of fish displaying complex behaviours as proof of consciousness. In response to commentaries on the idea that fish do not feel pain, I raise the need to go beyond just-so stories and to rigorously analyse the neural circuitry responsible for specific behaviours using new and emerging technologies in neuroscience. By deciphering the causal relationship between neural information processing and conscious behaviour, it should be possible to assess cogently the …

Spinning Our Wheels And Deepening The Divide: Call For An Evidence-Based Approach To The Fish Pain Debate, Steven J. Cooke

Animal Sentience

There is vigorous ongoing debate about whether fish feel pain and have the capacity to suffer. The body of literature dedicated to the topic is increasing but what is particularly problematic is that the majority of the contributions represent opinion pieces and thus fall within the realm of advocacy. Many of the empirical research papers purporting that fish do or do not feel pain have problems with cavalier use of definitions, poor experimental design, or statistical/technical issues and tend to include advocacy statements in their interpretations. Rather than continuing to spin our wheels and deepen the divide, I would advocate …

Fish Pain: Would It Change Current Best Practice In The Real World?, B. K. Diggles

Animal Sentience

Much of the “fish pain debate” relates to how high the bar for pain should be set. The close phylogenetic affinities of teleosts with cartilaginous fishes which appear to lack nociceptors suggests caution should be applied by those who seek to lower the bar, especially given the equivocal and conflicting nature of the experimental data currently available for teleosts. Nevertheless, even if we assume fish “feel pain,” it is difficult to see how current best practice in aquaculture would change. This is because of the need to avoid stress at all stages of the rearing process to optimize health, growth …

Leaving The Door Open For Fish Pain: Evolutionary Convergence And The Utility Of ‘Just-So Stories’, David B. Edelman

Animal Sentience

Key argues that fish do not experience pain because they lack the necessary (but not necessarily sufficient) brain structures and associated functional circuitry to engender such conscious percepts. I propose that fish pain may be dependent on neuroanatomical regions and pathways that are structurally and/or functionally analogous — but not strictly homologous — to well-characterized mammalian substrates of pain. An example is the convergent appearance of the complex, single-compartment eye across invertebrate and vertebrate phylogeny. Structural-functional convergence is ubiquitous in evolution. Comparative inferences and correlative lines of evidence play an important role in building evolutionary arguments. The dismissal of the …

Pain-Capable Neural Substrates May Be Widely Available In The Animal Kingdom, Edgar T. Walters

Animal Sentience

Neural and behavioral evidence from diverse species indicates that some forms of pain may be generated by coordinated activity in networks far smaller than the cortical pain matrix in mammals. Studies on responses to injury in squid suggest that simplification of the circuitry necessary for conscious pain might be achieved by restricting awareness to very limited information about a noxious event, possibly only to the fact that injury has occurred, ignoring information that is much less important for survival, such as the location of the injury. Some of the neural properties proposed to be critical for conscious pain in mammals …

How Not To Move The Line Drawn On Pain, Bjorn H. Merker

Animal Sentience

In this second commentary I outline the inadequacy of Key's responses to the many peer critiques of his thesis that have so far appeared in Animal Sentience. I illustrate with examples drawn from his response to my first commentary.

Nonverbal Indicators Of Pain, Simon Van Rysewyk

Animal Sentience

In discussing fish pain, Key (2016) privileges pain in humans — “the only species able to directly report on its feelings.” Human experience of pain is not necessarily best reflected by verbal self-report, however. Neural responses to noxious stimuli are influenced by individual differences and by context. Nonverbal pain displays such as facial expressions reflect part of the neural response to noxious stimuli. Most mammals have a specific facial grimace reflecting pain. If fish have a somatic expression of pain, the development of a reliable and accurate somatic pain scale specific to fish could make a contribution to the debate …

Fish Pain: An Inconvenient Truth, Culum Brown

Animal Sentience

Whether fish feel pain is a hot political topic. The consequences of our denial are huge given the billions of fish that are slaughtered annually for human consumption. The economic costs of changing our commercial fishery harvest practices are also likely to be great. Key outlines a structure-function analogy of pain in humans, tries to force that template on the rest of the vertebrate kingdom, and fails. His target article has so far elicited 34 commentaries from scientific experts from a broad range of disciplines; only three of these support his position. The broad consensus from the scientific community is …

About Fish, Humane Society Institute For Science And Policy

Aquaculture Collection

Although a number of fish species have been studied in their freshwater life stages, further research on the behavior and habitat requirements of ocean-going fish is required. While fishes have historically been regarded as more “primitive” than other vertebrate groups, Rodriguez et al concluded that several memory and learning systems of bony fishes are noticeably similar to those of reptiles, birds, and mammals. When animals as small and under appreciated as fish display complex mating systems, parental care, and demonstrate the ability to traverse significant distances using olfactory and celestial cues, it is clear that previously established definitions of intelligence …

The Use Of Animals In Higher Education: Problems, Alternatives, & Recommendations, Jonathan Balcombe

eBooks

Despite recent advances in technology and increasing societal concern for animals, animals continue to be exploited and killed in large numbers so that students can learn about their structure and function. Dissection may not be without its merits from an educational standpoint, if well implemented, but it appears from student surveys that it usually is not. When one considers the associated costs—animal suffering and death in the supply trade, disruption of wild animal populations, messages that tend to undermine rather than reinforce respect for life and concern for others, rising costs of animal carcasses (as compared with alternatives with longer …

A Function Of The Subelytral Chamber Of Tenebrionid Beetles, Con Slobodchikoff, Kim Wisman

Entomology Collection

1. The subelytral chamber is an air space between the elytra and the dorsum of the abdomen of some Tenebrionid beetles. Postulated functions for the subelytral chamber have been a reduction of transpiratory water loss and a thermal buffer for heat flow from the elytra to the abdomen.

2. We show that there is a significant correlation between water loss and the depth of the subelytral chamber.

3. This implies that the chamber may be a structure that permits the rapid expansion of the abdomen, providing the beetles with a mechanism by which they can quickly drink large quantities of …

Edging Toward Extinction: The Status Of Wildlife In Latin America, Douglas R. Shane

eBooks

No abstract provided.

The Behaviour Of Swine, J. P. Signoret, B. A. Baldwin, D. Fraser, E. S. E. Hafez

Mammalogy Collection

The pig was a forest-dwelling animal from the beginning of its history. In some parts of the world it has been domesticated for at least 7000 years. The European breeds of domestic swine were derived from the local wild pig, Sus scrofa. Herds ranged in pastures and forests and kept indoors only for fattening. The breeds in the Far East were derived from another wild pig, Sus vittatus, a smaller animal with shorter legs and a higher reproductive ability (Mohr 1960; Zeuner 1963). The two types interbred readily. The modem breeds of pig evolved from different crossings between the two …

Systematic And Evolutionary Implications Of Parthenogenesis In The Hymenoptera, C. N. Slobodchikoff, Howell V. Daly

Entomology Collection

Two types of parthenogenesis, arrhenotoky and thelytoky, exist in the Hymenoptera. Arrhenotoky, the development of males from unfertilized eggs, is present in all wasps and bees. Thelytoky, the development of diploid females from unfertilized eggs, is present in a few species. Two types of thelytoky, apomixis and automixis, are known. Most thelytokous Hymenoptera are automictic. No meiosis, only mitosis, occurs in apomixis. Meiosis does occur in automixis, allowing crossing-over and segregation of genes. Advantages of thelytoky are that heterotic combinations become fixed, gene loss is reduced, and reproduction requires only a single individual. One advantage of arrhenotoky is that genetic …