Meeting Abstract

78.5  Tuesday, Jan. 6  Morphological Integration of Moth Wing Patterns Cryptically Mimicking a Dead Leaf SUZUKI, Takao*; KURATANI, Shigeru; RIKEN CDB, Japan; RIKEN CDB, Japan tsuzuki@cdb.riken.jp

How animal body parts acquire adaptive patterns through changes in developmental program is a fundamental question of phenotypic evolution. Here, we report morphological integration seen in the moth wing in the evolution of mimesis.
As a model organism, we picked up a nocutuid moth, Oraesia excavata, whose forewing is thought to mimic a dead leaf by assuming a part of leaf vein system composed of one main nerve and two lateral veins. Using individuals collected in Mt. Rokko, Hyogo, Japan, we established a breeding system of this species in the laboratory. We measured phenotypic variation and correlation of each wing pattern element with statistical morphometrics, and found that the elements for the dead leaf showed variance several hundreds times lower than those among the others. These results suggested that the leaf pattern had been subjected to a stabilizing selection, to establish a rather invariant developmental patterning resistant to genetic variations. It was also indicated that these function-related characters (one main nerve and two lateral veins) had gained a dense correlation among themselves, strong enough to form a functional module to maintain the shape of a dead leaf. Futhermore, it was revealed that these modularity of wing pattern is not only produced by conserved homologous relationships, but also by novel relationships of pattern elements acquired by integration/percellation. These results suggested that the wing developmental program possess flexibility to create de novo modular architectures for ecological adaptation.