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NAUTILUSES, the closest living relatives of prehistoric ammonites, sniff out
their prey with a special pair of organs below their eyes, say biologists in the
US. Roger Hanlon of the Marine Biological Laboratory in Woods Hole and his
colleagues showed that the animals rely on organs called rhinopores to track
their prey. When the researchers temporarily blocked the rhinopores with a blob
of paraffin jelly, the animals had difficulty finding their prey. But with both
organs clear, they unerringly homed in on their prey from more than 10 metres
away (The Journal of Experimental Biology, vol 203, p 1409). The
researchers think the ammonites and belemnites that dominated the seas 400
million years ago used the same technique.