Fish Intelligence, Sentience and Ethics

Fish are one of the most highly utilised vertebrate taxa by humans; they are harvested from wild stocks as part of global fishing industries, grown under intensive aquaculture conditions, are the most common pet and are widely used for scientific research. But fish are seldom afforded the same level of compassion or welfare as warm-blooded vertebrates. Part of the problem is the large gap between people’s perception of fish intelligence and the scientific reality. This is an important issue because public perception guides government policy. The perception of an animal’s intelligence often drives our decision whether or not to include them in our moral circle. From a welfare perspective, most researchers would suggest that if an animal is sentient, then it can most likely suffer and should therefore be offered some form of formal protection. There has been a debate about fish welfare for decades which centres on the question of whether they are sentient or conscious. The implications for affording the same level of protection to fish as other vertebrates are great, not least because of fishing-related industries. Here, I review the current state of knowledge of fish cognition starting with their sensory perception and moving on to cognition. The review reveals that fish perception and cognitive abilities often match or exceed other vertebrates. A review of the evidence for pain perception strongly suggests that fish experience pain in a manner similar to the rest of the vertebrates. Although scientists cannot provide a definitive answer on the level of consciousness for any nonhuman vertebrate, the extensive evidence of fish behavioural and cognitive sophistication and pain perception suggests that best practice would be to lend fish the same level of protection as any other vertebrate

Aggression, anxiety and vocalizations in animals: GABA A and 5-HT anxiolytics

A continuing challenge for preclinical research on anxiolytic drugs is to capture the affective dimension that characterizes anxiety and aggression, either in their adaptive forms or when they become of clinical concern. Experimental protocols for the preclinical study of anxiolytic drugs typically involve the suppression of conditioned or unconditioned social and exploratory behavior (e.g., punished drinking or social interactions) and demonstrate the reversal of this behavioral suppression by drugs acting on the benzodiazepine-GABA A complex. Less frequently, aversive events engender increases in conditioned or unconditioned behavior that are reversed by anxiolytic drugs (e.g., fear-potentiated startle). More recently, putative anxiolytics which target 5-HT receptor subtypes produced effects in these traditional protocols that often are not systematic and robust. We propose ethological studies of vocal expressions in rodents and primates during social confrontations, separation from social companions, or exposure to aversive environmental events as promising sources of information on the affective features of behavior. This approach focusses on vocal and other display behavior with clear functional validity and homology. Drugs with anxiolytic effects that act on the benzodiazepine-GABA A receptor complex and on 5-HT 1A receptors systematically and potently alter specific vocalizations in rodents and primates in a pharmacologically reversible manner; the specificity of these effects on vocalizations is evident due to the effectiveness of low doses that do not compromise other physiological and behavioral processes. Antagonists at the benzodiazepine receptor reverse the effects of full agonists on vocalizations, particularly when these occur in threatening, startling and distressing contexts. With the development of antagonists at 5-HT receptor subtypes, it can be anticipated that similar receptor-specificity can be established for the effects of 5-HT anxiolytics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46351/1/213_2005_Article_BF02245590.pd

Arctic amplification decreases temperature variance in northern mid- to high-latitudes

Copyright © 2014 Nature Publishing GroupChanges in climate variability are arguably more important for society and ecosystems than changes in mean climate, especially if they translate into altered extremes [1, 2, 3]. There is a common perception and growing concern that human-induced climate change will lead to more volatile and extreme weather [4]. Certain types of extreme weather have increased in frequency and/or severity [5, 6, 7], in part because of a shift in mean climate but also because of changing variability [1, 2, 3, 8, 9, 10]. In spite of mean climate warming, an ostensibly large number of high-impact cold extremes have occurred in the Northern Hemisphere mid-latitudes over the past decade [11]. One explanation is that Arctic amplification—the greater warming of the Arctic compared with lower latitudes [12] associated with diminishing sea ice and snow cover—is altering the polar jet stream and increasing temperature variability [13, 14, 15, 16]. This study shows, however, that subseasonal cold-season temperature variability has significantly decreased over the mid- to high-latitude Northern Hemisphere in recent decades. This is partly because northerly winds and associated cold days are warming more rapidly than southerly winds and warm days, and so Arctic amplification acts to reduce subseasonal temperature variance. Previous hypotheses linking Arctic amplification to increased weather extremes invoke dynamical changes in atmospheric circulation [11, 13, 14, 15, 16], which are hard to detect in present observations [17, 18] and highly uncertain in the future [19, 20]. In contrast, decreases in subseasonal cold-season temperature variability, in accordance with the mechanism proposed here, are detectable in the observational record and are highly robust in twenty-first-century climate model simulations.Natural Environment Research Council (NERC

A meta-analysis of correlated behaviours with implications for behavioural syndromes: Mean effect size, publication bias, phylogenetic effects and the role of mediator variables

In evolutionary and behavioural ecology, increasing attention is being paid to the fact that functionally distinct behaviours are often not independent from each other. Such phenomenon is labelled as behavioural syndrome and is usually demonstrated by phenotypic correlations between behaviours like activity, exploration, aggression and risk-taking across individuals in a population. However, published studies disagree on the strength, and even on the existence of such relationships. To make general inferences from this mixed evidence, we quantitatively reviewed the literature using modern meta-analytic approaches. Based on a large dataset, we investigated the overall relationship between behaviours that are expected to form a syndrome and tested which factors can mediate heterogeneities in study outcomes. The average strength of the phenotypic correlation between behaviours was weak; we found no effect of the phylogeny of species but did observe significant publication bias. However, even accounting for this bias, the mean effect size was positive and statistically different from zero (r = 0. 198). Effect sizes showed considerable heterogeneity within species, implying a role for population-specific adaptation to environmental factors and/or between-study differences in research design. There was a significant positive association between absolute effect size and repeatability of behaviours, suggesting that within-individual variation of behavioural traits can set up an upper limit for the strength of the detected phenotypic correlations. Moreover, spatial overlap between the contexts in which different behaviours were assayed increased the magnitude of the association. The small effect size for the focal relationship implies that a huge sample size would be required to demonstrate a correlation between behaviours with sufficient statistical power, which is fulfilled only in very few studies. This suggests that behavioural syndromes often remain undetected and unpublished. Collectively, our meta-analysis revealed a number of points that might be worth to consider in the future study of behavioural syndromes. © 2012 The Author(s).Peer Reviewe