Ueda Sayoko, Kumagai Gaku, Otaki Yusuke, Yamaguchi Shinya, Kohshima Shiro
Tokyo Institute of Technology, Tokyo, Japan; Wildlife Research Center of Kyoto University, Kyoto, Japan.
Tama Zoological Park, Tokyo Zoological Park Society, Tokyo, Japan.
PLoS One. 2014 Jun 11;9(2):e98217. doi: 10.1371/journal.pone.0098217. eCollection 2014.
As facial color pattern around the eyes has been suggested to serve various adaptive functions related to the gaze signal, we compared the patterns among 25 canid species, focusing on the gaze signal, to estimate the function of facial color pattern in these species. The facial color patterns of the studied species could be categorized into the following three types based on contrast indices relating to the gaze signal: A-type (both pupil position in the eye outline and eye position in the face are clear), B-type (only the eye position is clear), and C-type (both the pupil and eye position are unclear). A-type faces with light-colored irises were observed in most studied species of the wolf-like clade and some of the red fox-like clade. A-type faces tended to be observed in species living in family groups all year-round, whereas B-type faces tended to be seen in solo/pair-living species. The duration of gazing behavior during which the facial gaze-signal is displayed to the other individual was longest in gray wolves with typical A-type faces, of intermediate length in fennec foxes with typical B-type faces, and shortest in bush dogs with typical C-type faces. These results suggest that the facial color pattern of canid species is related to their gaze communication and that canids with A-type faces, especially gray wolves, use the gaze signal in conspecific communication.
由于有人提出眼睛周围的面部颜色模式具有与注视信号相关的各种适应性功能，我们比较了25种犬科动物的模式，重点关注注视信号，以估计这些物种中面部颜色模式的功能。根据与注视信号相关的对比度指数，所研究物种的面部颜色模式可分为以下三种类型：A型（眼睛轮廓中的瞳孔位置和面部中的眼睛位置都清晰）、B型（只有眼睛位置清晰）和C型（瞳孔和眼睛位置都不清晰）。在大多数狼类分支和一些赤狐类分支的研究物种中观察到虹膜浅色的A型面孔。全年生活在家族群体中的物种往往具有A型面孔，而单独/成对生活的物种则往往具有B型面孔。向其他个体展示面部注视信号的注视行为持续时间，在具有典型A型面孔的灰狼中最长，在具有典型B型面孔的耳廓狐中中等长度，在具有典型C型面孔的薮犬中最短。这些结果表明，犬科动物的面部颜色模式与其注视交流有关，具有A型面孔的犬科动物，尤其是灰狼，在同种交流中使用注视信号。
