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Uesugi K
Mimicry in Papilio polytes and its ecological meaning.
In: Swallowtail Butterflies: Their Ecology & Evolutionary Biology
Edited by J. Mark Scriber, Yoshitaka Tsubaki and Robert C. Lederhouse. pp. 165-172.
Scientific Publishers, Inc. P.O. Box 15718, Gainesville, FL 32604 (1995)

On the Ryukyu Islands, the northernedge of the biogeographical range of Papilio polytes, the female has two forms, f. cyrus and f. polytes, but the male is monomorphic. F. cyrus is non-mimic and resembles the male, but f. polytes mimics Pachiopta aristolochiae. Pach. aristolochiae was established around 1968 and 1975 in the Yaeyama Islands and Miyako Islands, respectively. Following this, P. polytes f. polytes has increased.

Temporal change in the relative abundance of the mimic (f. polytes) among all female forms of P. polytes (=mimetic form rate ; MFR) has increased approximately logistically and reached an equilibrium level after the establishment of the model Pach. aristolochiae on Miyako-jima Island. The Advantage Index of Batesian Mimicry (AIB) indicates the probability of a predator learning to avoid a model. There was a significant positive association between AIB and MFR in Yaeyama and Miyako islands in 1982.

From my field surveys, greater selective feeding pressure was placed on the mimic by avian predators after a strong typhoon. Seven caged brown-earned bulbuls, Hypsipetes amaurotis pryeri, were offered the model at one of two feeders. After experiencing the model, the birds consumed less feed thereafter from the feeder where a model had been experienced.