Location of fruit using only airborne odor cues by a lizard

Although squamate reptiles are known to locate conspecifics by scent-traili ng and to locate and identify prey by tongue-flicking substrates, an abilit y to locate food using only airborne cues has previously only been suspecte d based on observations that dead animals can be used as bait for Komodo dr agons and that some nocturnal geckos aggregate on flowers. We conducted a s imple field test of the ability of the omnivorous lizard Podarcis lilfordi to find fruit hidden under opaque cups. When a board having two identical c ups spaced 1 m apart, one empty and the other hiding a freshly cut piece of apricot, was placed in the habitat, lizards first contacted the cup hiding fruit at well above chance frequency. Upon contact with a cup, lizards wer e significantly more likely to stay next to the cup, tongue-flick at high r ates, climb the cup, and attempt to bite the cup if it hid a piece of apric ot. The ability to follow a concentration gradient of airborne volatile che micals to its source is very likely mediated by olfaction, but participatio n by or primacy of vomerolfaction cannot be excluded. (C) 2001 Elsevier Sci ence Inc. All rights reserved.