Color discrimination at the spatial resolution limit in a swallowtail butterfly, Papilio xuthus

• 木下, 充代

• TAKEUCHI, Yuichi

• ARIKAWA, Kentaro

• KINOSHITA, Michiyo

抄録

application/pdf

Spatial resolution of insect compound eyes is much coarser than that of humans: a single pixel of the human visual system covers about 0.008° whereas that of diurnal insects is typically about 1.0°. Anatomically, the pixels correspond to single cone outer segments in humans and to single rhabdoms in insects. Although an outer segment and a rhabdom are equivalent organelles containing visual pigment molecules, they are strikingly different in spectral terms. The cone outer segment is the photoreceptor cell part that expresses a single type of visual pigment, and is therefore monochromatic. On the other hand, a rhabdom is composed of several photoreceptor cells with different spectral sensitivities and is therefore polychromatic. The polychromatic organization of the rhabdom suggests that insects can resolve wavelength information in a single pixel, which is an ability that humans do not have. We first trained the Japanese yellow swallowtail butterfly Papilio xuthus to feed on sucrose solution at a paper disk of certain color. We then let the trained butterflies discriminate disks of the training color and grey disks each presented in a Y-maze apparatus. Papilio correctly selected the colored disk when the visual angle was greater than 1.18° for blue, 1.53° for green or 0.96° for red: they appeared to see colors in single pixels to some extent. This ability may compensate their rather low spatial resolution.

収録刊行物

• Journal of Experimental Biology

  Journal of Experimental Biology 209 (15), 2873-2879, 2006-05-04

  The Company of Biologists Ltd

詳細情報

• CRID: 1050845763858302848
• NII論文ID: 120006576014
• ISSN: 00220949
• Web Site: https://ir.soken.ac.jp/records/3327
• 本文言語コード: en
• 資料種別: journal article
• データソース種別:
  • IRDB
  • CiNii Articles