Electroreception in monotremes
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چکیده
subject of special fascination ever since their first description was greeted by Western scientists with great scepticism (Home, 1802). Many thought that the platypus was a clever hoax perpetrated by careful attachment of a duck-bill and webbed feet to the skin of a mammal (Griffiths, 1998). Perhaps a greater mystery concerned the ability of a platypus to catch half its body mass of benthic invertebrates under water on the darkest night with all of its obvious sensory channels (eyes, ears and nostrils) tightly closed. The ‘sixth sense’ suggested to explain this puzzling ability (Burrell, 1927) has finally proved to be the bill sense, a sophisticated combination of electroreception and mechanoreception that coordinates the information about aquatic prey provided from the bill skin by 100 000 separately innervated mechanoreceptors and electroreceptors.
منابع مشابه
Electroreception in the Guiana dolphin (Sotalia guianensis).
Passive electroreception is a widespread sense in fishes and amphibians, but in mammals this sensory ability has previously only been shown in monotremes. While the electroreceptors in fish and amphibians evolved from mechanosensory lateral line organs, those of monotremes are based on cutaneous glands innervated by trigeminal nerves. Electroreceptors evolved from other structures or in other t...
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تاریخ انتشار 1999