The palatability and the ability of neotropical butterflies to escape after being detected, attacked and captured by wild kingbirds (Tyrannus melancholicus Vieillot), was investigated by the release of 668 individuals of 98 butterfly species close to the birds, during their usual feeding activities. Most of the butterflies were attacked and eaten. Only the troidine swallowtails (Parides and Battus; Papilionidae) were consistently rejected on taste and elicited aversive behaviours in birds. Most other aposematic and/or mimetic species in the genera Danaus and Lycorea (Danainae), Dione, Eueides and Heliconius (Heliconiinae), Hypothyris, Mechanitis and Melinaea (Ithomiinae), Biblis, Callicore and Diaethria (Limenitidinae) were generally eaten. Cryptic and non-mimetic species were always attacked and, if captured, they were also eaten. All Apaturinae, Charaxinae, Nymphalinae, Hesperidae, most Limenitidinae, Heliconiinae (Agraulis, Dryas, Dryadula and Philaethria) and Papilionidae (Eurytides, Heraclides and Protesilaus) were in this group. Results indicate that the learning process in kingbirds may demand a large mortality in prey populations, even among species generally accepted as unpalatable and aposematic. They also support the assertion that escaping ability and unpalatability evolved in butterflies as alternative strategies to avoid predation by birds. Mimetic relationships among several species are discussed. Evidence for the evolution of aposematism not related to unpalatability, but to escaping ability, was found for two hardto-catch Morpho species.

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Bwbgical Journal ~f t t u Linnean society (1996), 59: 351-365. With 2 figures j-/ 7 4 PbA Palatablility and esc-ing ability in Neotropical butted&: tests with wild kingbirds (Tfiannus melan2holicu~Tyrannidae) 7 CARLOS E.G. PINHEIRO Department of elicited avers% beham3urs in birds. Most o G r a p o s a t i c and/or mimetic species in the gezra Danaur and Lycorea (Danainae), fitm,~uci& and Heliconiuc (Heliconiinae), H@Thyris, Mechanilir and M d s a (IthomGae), Bi?%is, Callipre an2 Dirulhria &en&dinaqwere g e n e a y e a t e n 2 P t i c and n&nimeticypecies weE always attacked a n c i f captured, they were also eaten. AU Apaturinae, Charaxinae, Nymphalinae, Hesperidae, most Limenitidinae, Heliconiins -&raulis, &as, & -& I .and F%i $&i a) and PaFdionidae (Eu-&h, Hcratlidw and%oorcsilnils) were in this group. Results indicze that thhearning p r o c e G kin&ir%may deEand a large-mortality in prey opulations, even among species gy accepted as unpetable and aposetmatic. Thr'o supp/ort -f i e assertion that esca&g ability and unpalsbility evolved in butterflies as alternative strategies to avoid predation by bi r r & Mimetic relationships among several specigare discussed. Evidence for the evolution of aposzatism not a a t e d to unpalatability, but to escaping ability, was found for two hardto-catch Morpho species. h -\ 01996 The Linnean Society of London ADDITIONAL

The selective advantage of Miillerian mimicry in nature was investigated by releasing live mimetic and nonmimetic butterflies close to wild, aerial-hunting tropical kingbirds ( Grannw melancholzcus) and cliff-flycatchers (Hirundinea firruginea) in three Amazon habitats (rain forest, a city, and "canga" vegetation). Only mimetic butterflies elicited sight-rejections by birds, but protection conferred by mimicry was restricted to sites in which both predators and mimics co-occurred, as in the case of six mimicry rings at a forest site and two at a city site. Most other Miillerian mimics released at city and canga vegetation were heavily attacked and consumed by birds. These results appear to reflect the birds' previous experiences with resident butterfly faunas and illustrate how birds' discriminatory behavior varied among habitats that differed in butterfly species and mimicry ring composition.

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