October 2015 UTC Just responding to requests to verify my statements As for specific changes I have looked again and think in the first section the last 3 paragraphs can be sorted out as follows Fish fulfill several criteria proposed by some scientists as indicating that non human animals may experience pain These criteria include a suitable nervous system and sensory receptors opioid receptors and reduced responses to noxious stimuli when given analgesics and local anaesthetics physiological changes to noxious stimuli displaying protective motor reactions exhibiting avoidance learning and making trade offs between noxious stimulus avoidance and other motivational requirements However other scientists point out there are several neurobiological features in teleost fish and elasmobranchs that suggest they are unlikely to be capable of pain perception Because of this there is currently no scientific consensus on the topic which remains controversial Pain in fish has societal implications including their suffering when exposed to pollutants in commercial and sporting fisheries aquaculture in ornamental fish and for fish used in scientific research 00 03 26