Electroreception in monotremes

I will briefly review the history of the bill sense of the platypus, a soph isticated combination of electroreception and mechanoreception that coordin ates information about aquatic prey provided from the bill skin mechanorece ptors and electroreceptors, and provide an evolutionary account of electror eception in the three extant species of monotreme (and what can be inferred of their ancestors). Electroreception in monotremes is compared and contra sted with the extensive body of work an electric fish, and an account of th e central mechanoreceptive and electroreceptive input In the somatosensory neocortex of the platypus, where sophisticated calculations seem to enable a complete three-dimensional fix on prey, is given.