Research that counters the hypothesis

Okay, I know I said I was going to post this on Monday, but that was a lie. Better late than never! (Note: this post is not late in the sense that points should be deducted; in fact, it is technically quite early.) In my last post, I described a study led by Dr. Lynne Sneddon from The Roslin Institute that appeared to give conclusive evidence of the presence of pain in fish. However, with every new piece of evidence, Dr. James L. Rose from the University of Wyoming seems determined to try and refute it. In his critique of the study by Sneddon et al., Rose lists several reasons why he thinks the study should not be considered particularly valid evidence for pain in fish.

For one thing, Rose accuses Sneddon et al. of assuming that "any behavior that is a reflex would be evidence of nociception but any behavior more complex than a reflex would be evidence of
pain." He invalidates this assumption by pointing to certain instances where humans themselves make certain complex, non-reflexive responses to harmful stimuli without being conscious (and therefore, not feeling pain)—for example, humans with "extensive damage" of the cerebral hemispheres.

Rose goes on to provide evidence (the lack of a neocortex) that fish do not have the capacity for pain, and perhaps not even the capacity for consciousness. "The burden of proof," he says, lies with Sneddon et al. to show that trout have the biological capacity to feel pain. The so-called "conclusive evidence" suggested by Sneddon, Rose claims, arose "only by citing previous studies that also used invalid criteria for pain, such as avoidance learning, which actually occurs unconsciously." He also accuses Sneddon of anthropomorphism.

Rose also provides reasons for why the behavioral results allegedly showing evidence of pain were "misinterpreted"—vast differences in the fish neurology compared to mammal neurology, as well alternative, apparently more plausible explanations for the "pained" fishes' behaviors.

This is not the only time Dr. Rose has criticized studies of fish pain. In fact, in one of his articles, Rose et al. commented on more than a dozen studies (including some by Sneddon, and another significant study by Nordgreen et al. that studied the reactions of fish to high heat), and "refuted" all of their reasonings that led to the conclusions that fish feel pain, through some of his logic stated above. Sneddon responded to Rose (rather acrimoniously, in fact) by criticizing him for his lack of a "track record" in animal neurology, for inserting his own "personal opinion[s]" into his work, and for implying that one can disprove but not prove the existence of pain in fish. Sneddon responds to Rose's anthropomorphism remark by accusing Rose himself of anthropomorphism by assuming that fish's bodies work the same ways humans' do. In his article "The Welfare of Fish," Professor George Iwama of Acadia University, while agreeing with many of Rose's points, conquers with Sneddon that "the basis for our respectful treatment" of fish should not rely "upon the outcome that fish...experience pain as we do."

Dr. Rose makes many good points. However, I would agree with Sneddon that he seems to be taking the "burden of proof" concept too far. Although I might agree with him that we cannot conclusively say that fish feel pain (like Sneddon seems to say), I don't agree that every pro-fish-pain conclusion by every study is automatically invalid. These studies aren't proof of fish pain, and maybe not even evidence beyond a reasonable doubt, but they can certainly still be considered evidence. Rose can go ahead and invalidate some of the conclusions certain researchers make, but he shouldn't discredit the research entirely. This is surely a topic worthy of further study.