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Full-Text Articles in Evolution

Should Fish Feel Pain? A Plant Perspective, František Baluška Jan 2016

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 …


Pain-Capable Neural Substrates May Be Widely Available In The Animal Kingdom, Edgar T. Walters Jan 2016

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 …


Why Fish Do Not Feel Pain, Brian Key Jan 2016

Why Fish Do Not Feel Pain, Brian Key

Animal Sentience

Only humans can report feeling pain. In contrast, pain in animals is typically inferred on the basis of nonverbal behaviour. Unfortunately, these behavioural data can be problematic when the reliability and validity of the behavioural tests are questionable. The thesis proposed here is based on the bioengineering principle that structure determines function. Basic functional homologies can be mapped to structural homologies across a broad spectrum of vertebrate species. For example, olfaction depends on olfactory glomeruli in the olfactory bulbs of the forebrain, visual orientation responses depend on the laminated optic tectum in the midbrain, and locomotion depends on pattern generators …


Fish Lack The Brains And The Psychology For Pain, Stuart W.G. Derbyshire Jan 2016

Fish Lack The Brains And The Psychology For Pain, Stuart W.G. Derbyshire

Animal Sentience

Debate about the possibility of fish pain focuses largely on the fish’s lack of the cortex considered necessary for generating pain. That view is appealing because it avoids relatively abstract debate about the nature of pain experience and subjectivity. Unfortunately, however, that debate cannot be entirely avoided. Subcortical circuits in the fish might support an immediate, raw, “pain” experience. The necessity of the cortex only becomes obvious when considering pain as an explicitly felt subjective experience. Attributing pain to fish only seems absurd when pain is considered as a state of explicit knowing.


What Would The Babel Fish Say?, Monica Gagliano Jan 2016

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 …


Animal Sentience: The Other-Minds Problem, Stevan Harnad Jan 2016

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 …


Going Beyond Just-So Stories, Brian Key Jan 2016

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 …


Animal Suffering Calls For More Than A Bigger Cage, Simon R. B. Leadbeater Jan 2016

Animal Suffering Calls For More Than A Bigger Cage, Simon R. B. Leadbeater

Animal Sentience

Ng (2016) argues for incremental welfare biology partly because it would be impossible to demonstrate conclusively that animals are sentient. He argues that low cost changes in industrial practices and working collaboratively may be more effective in advancing animal welfare than more adversarial approaches. There is merit in some of Ng’s recommendations but a number of his arguments are, in my view, misdirected. The fact that nonhuman animals feel has already been adequately demonstrated. Cruelty to animals is intrinsic to some industries, so the only way to oppose it is to oppose the industry.