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Foraging modes (ambush vs. active foraging) are often correlated with a suite of morphological, physiological, behavioural and ecological traits known as the "adaptive syndrome" or "syndrome hypothesis." In snakes, an ecological correlate often reported in the literature is that ambush‐hunting snakes have a higher relative meal size compared to actively foraging snakes which feed on smaller prey items. This “large meal versus small meal” feeding hypothesis between ambush and active foragers has become a widely accepted paradigm of snake feeding ecology, despite the fact that no rigorous meta‐analysis has been conducted to support this generalization. We conducted a phylogenetically explicit meta‐analysis, which included ca. 100 species, to test this paradigm of snake feeding ecology. We gathered data on prey size by inducing regurgitation by palpation in free‐ranging snakes and by examining the stomach contents of preserved museum specimens. When we found prey, we recorded both snake and prey mass to estimate relative prey mass (prey mass/snake mass). We also reviewed published studies of snake feeding ecology to gather similar information for other species. Ambush and active foragers did not differ in minimum or average meal size but the maximum meal sizes consumed by ambush‐foraging snakes were larger than the maximum meal sizes eaten by active foragers. This results in ambush‐foraging snakes consuming a significantly wider range of meal sizes, rather than being large meal specialists compared to active foragers. We argue that ambush foragers evolved to be more opportunistic predators because they encounter prey less frequently compared to active foragers. This hypothesis is further supported by the fact that ambush foragers also exhibited marginally wider diet breadths, consuming a broader range of prey types in comparison with active foragers. Our study challenges aspects of the foraging syndrome as it is currently conceived, and our results have important implications for our understanding of how foraging mode has shaped the behaviour and physiology of ambush‐foraging snakes.

Gravid female Malawian Pseudotropheus cichlids spent significantly more time with males that they subsequently chose as mates, indicating that time spent near a male is a valid and accurate method of measuring female preference. Furthermore, females preferred to mate with males that had longer pelvic fins and a larger number of eggspots on their anal fins. In some instances, females chose to mate with both of the males with which they were presented, possibly because they were unable to discriminate between them. 2001 The Fisheries Society of the British Isles

Snake farming in Asia has increased over the past decade, and conservationists have expressed concerns that farms may foster overexploitation of wild populations and create legal conduits for illegally harvested wild individuals. We conducted face-to-face interviews with snake farmers in Viet Nam and China, with the aim of describing the basic models under which snakes are farmed for meat. We synthesized this information to assess the feasibility of farming snakes for human consumption, drawing conclusions about the impact of this industry on the conservation of wild snake populations. The most commonly farmed snakes include the monocled cobra Naja kaouthia, the Chinese cobra Naja atra, the oriental rat snake Ptyas mucosus and the king cobra Ophiophagus hannah. These species have life histories that are compatible with the demands of intensive livestock production, including early maturity, rapid growth rates, high reproductive output, efficient food assimilation rates and undemanding space requirements. Snake farmers appear to be capitalizing on the unique energy-efficiency of snakes to produce meat for human consumption. We conclude that the ease and profitability of farming snakes in China and Viet Nam make farming a viable substitute for harvesting wild snakes, with apparently minimal threat to wild populations. Snake farming offers a range of novel agricultural opportunities and has the potential to play a pivotal role in sustainable development.

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