Dimorphism of both head and prothoracic horn morphologies in male Copris acutidens (Coleoptera: Scarabaeoidea) |
| |
Authors: | Mayumi Akamine |
| |
Institution: | Department of Forest Science and Resources, College of Bioresource Sciences, Nihon University, Fujisawa, Japan |
| |
Abstract: | Allometric scaling of male horn morphologies of Copris acutidens, including the head and prothoracic horns, was analyzed. The analyses of scaling relationships indicated a discontinuous increase in head horn length and prothoracic horn height but a linear increase in prothoracic horn length relative to body size. The different results for length and height of the prothoracic horn suggest that the height is functionally more important for ensuring mates in the nests. Furthermore, both the head and prothoracic horns were dimorphic, and this characteristic was not found in the scarabaeoid beetle Onthophagus. Similarity in the switch point values for the head and prothoracic horns suggests that the dimorphism of the two kinds of horns may result from the same developmental threshold mechanism. |
| |
Keywords: | discontinuous pattern dung beetle Eberhard and Gutié rrez models scaling relationship sexual dimorphism |
|
|