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Summary1. Frugivory among bats (Chiroptera) has evolved independently in the New and Old World tropics: within the families Phyllostomidae and Pteropodidae, respectively. Bats from both families rely primarily on olfaction for the location of fruits. However, the influence of bats on the evolution of fruit scent is almost completely unknown. 2. Using the genus Ficus as a model, the aims of this study were to explore the chemical composition of fruit scent in relation to two contrasting seed dispersal syndromes in Panama and Malaysia and to assess the influence of fruit scent on the foraging behaviour of neo-and palaeotropical fruit-eating bats (Artibeus jamaicensis and Cynopterus brachyotis, respectively). Two hypotheses were tested: (i) variation in fruit scent, between bat-and bird-dispersed figs, is independent of phylogeny and (ii) Old and New World fruit bats, which have evolved independently in each hemisphere, share the same olfactory preferences with respect to fruit scent. 3. The fruit scents of bat-and bird-dispersed fig species were sampled in the field, using dynamic headspace adsorption techniques. New and Old World fruit bats were then captured and tested on natural fig fruit scents from both hemispheres. 4. Chemical analyses, using gas chromatography (GC) and GC/mass spectrometry (MS), revealed a broad overlap in scent compounds between bat-dispersed fig species from both hemispheres. Their fruit scents were dominated by monoterpenes, which contrary to phylogenetic predictions, were completely absent from bird-dispersed species from both regions. 5. The fruit scents of bat-dispersed figs were highly attractive to neotropical bats (A. jamaicensis) in behavioural experiments, whereas those of bird-dispersed figs were completely rejected. Neotropical bats (A. jamaicensis) exhibited a significant preference for fig fruit scents dominated by monoterpenes, independent of the geographical origin of the scent. Palaeotropical bats (C. brachyotis), by contrast, rejected monoterpene-rich fruit scents from the Neotropics. 6. In a cluster analysis (which included additional, published data from the literature), the fruit scents of bat-dispersed figs were clumped by subgenus, with the exception of palaeotropical figs of the subgenus Sycomorus. C. brachyotis, from Malaysia, was the only fruit bat species that significantly preferred the fruit scents of Sycomorus figs that contained no monoterpenes.

The essential oil in leaves of Polygonum minus Huds., a local aromatic plant, were identified by a pipeline of gas chromatography (GC) techniques coupled with mass-spectrometry (MS), flame ionization detector (FID) and two dimensional gas chromatography time of flight mass spectrometry (GC×GC–TOF MS). A total of 48 compounds with a good match and high probability values were identified using this technique. Meanwhile, 42 compounds were successfully identified in this study using GC-MS, a significantly larger number than in previous studies. GC-FID was used in determining the retention indices of chemical components in P. minus essential oil. The result also showed the efficiency and reliability were greatly improved when chemometric methods and retention indices were used in identification and quantification of chemical components in plant essential oil.

We investigated the fruit odors of two bat-dispersed fig species in the Paleotropics, in relation to the foraging behavior of fruit bats, to test the following hypotheses: 1) fruit odor plays a critical role for detection and selection of ripe figs by fruit bats; 2) bat-dispersed fig species are characterized by the same, or similar, chemical compounds; and 3) total scent production, in bat-dispersed figs, increases when fruits ripen. We performed bioassays to test the effect of both natural and synthetic fig fruit odors on the foraging behavior of the short-nosed fruit bat (Cynopterus brachyotis)-an important disperser of figs within the study area. Fruit bats responded to both visual and chemical (olfactory) cues when foraging for figs. However, the strongest foraging reaction that resulted in a landing or feeding attempt was almost exclusively associated with the presence of a ripe fruit odor-either in combination with visual cues or when presented alone. Fruit bats also used fruit odors to distinguish between ripe and unripe fruits. By using gas chromatography (GC) and GC/mass spectrometry (MS), a total of 16 main compounds were identified in the ripe fruit odor of Ficus hispida and 13 in the ripe fruit odor of Ficus scortechinii-including alcohols, ketones, esters, and two terpenes. Additional compounds were also recorded in F. hispida, but not identified-four of which also occurred in F. scortechinii. Total scent production increased in both species when fruits ripened. Both natural and synthetic fruit odors resulted in feeding attempts by bats, with no feeding attempts elicited by unscented controls. Reaction rates to natural fruit odors were higher than those to synthetic blends.

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