title: Physiologically induced color-pattern changes in butterfly wings: mechanistic and evolutionary implications.
abstract: A mechanistic understanding of the butterfly wing color-pattern determination can be facilitated by experimental pattern changes. Here I review physiologically induced color-pattern changes in nymphalid butterflies and their mechanistic and evolutionary implications. A type of color-pattern change can be elicited by elemental changes in size and position throughout the wing, as suggested by the nymphalid groundplan. These changes of pattern elements are bi-directional and bi-sided dislocation toward or away from eyespot foci and in both proximal and distal sides of the foci. The peripheral elements are dislocated even in the eyespot-less compartments. Anterior spots are more severely modified, suggesting the existence of an anterior-posterior gradient. In one species, eyespots are transformed into white spots with remnant-like orange scales, and such patterns emerge even at the eyespot-less "imaginary" foci. A series of these color-pattern modifications probably reveal "snap-shots" of a dynamic morphogenic signal due to heterochronic uncoupling between the signaling and reception steps. The conventional gradient model can be revised to account for these observed color-pattern changes.
authors.affiliation: The BCPH Unit of Molecular Physiology, Laboratory of Cell and Functional Biology, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan. otaki@sci.u-ryukyu.ac.jp
authors.forename: Joji M
authors.initials: JM
authors.lastname: Otaki
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002080:Butterflies / Q000033:anatomy & histology / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D003116:Color; D009024:Morphogenesis; D010641:Phenotype; D015398:Signal Transduction; D014921:Wings, Animal / Q000033:anatomy & histology / Q000737:chemistry / Q000254:growth & development / Q000502:physiology*