A Model for Cellular Pattern Formation of Scales in a Butterfly Wing

Toshio Sekimura¹ and Akihiro Yoshida²

¹College of Engineering, Chubu University, Kasugai, Aichi 487, Japan
²Life Science Institute, Sophia University, Kioicho, Chiyoda-ku, Tokyo 102, Japan

(Received July 1, 1990; Accepted November 1, 1990)

Keywords: Cellular Pattern Formation, Scale Cell, Butterfly Wing

Abstract. The cellular pattern in a lepidopteran wing has two main characteristics. First, the scales of the wing form nearly straight parallel rows in the anteroposterior direction, and second, these rows are arranged at regular interval in the proximodistal direction. We investigated the mechanism of the cellular pattern formation by computer simulations in a two-dimensional discrete model. In comparison with experimental observations, we have obtained following results: 1) Lateral inhibition in scale cell differentiation should be working to form the uniformly distributed pattern of scale precursor cells. 2) The periodic cellular pattern in the wing can be formed by differential chemotaxis and/or position-specific differential cell adhesion. 3) In order to estimate the ratio of scale precursor cells to all the cells in the wing, it is necessary to account for size differences between the scale precursor cell and the undifferentiated epidermal cell.