ISSN:
1432-1351
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
,
Medizin
Notizen:
Summary To unravel possible morphological differences between the fovea and the non-fovea areas, a planar map of the praying mantis eye was built up. It consisted in a projection of the frontal part of the eye on to a flat surface preserving the area characteristics. The radii of curvature, the number of ommatidia per unit area and the ommatidium area for different zones of the eye were calculated. 1.Comparisons between the hitting ability showed by the 16 experimental groups described in the previous paper (Maldonado and Barrós-Pita, 1970) was compared to the corresponding area and to the number of ommatidia covered by paint. The correlation between these values did not significantly differ from zero. This finding confirms that, concerning distance estimation, the frontal part of the eye does not work on the basis of the mass-action principle. 2.Different zones of the fovea were compared with the enclosed non-fovea (zone B, Fig. 5). The fovea proved to have a smaller radius of curvature and a greater concentration of ommatidia (Fig. 6 and 7). These two morphological peculiarities enable the fovea of one eye, working with the complementary fovea of the other eye, to elicit a great density of triangulation. This finding support the hypothesis that a precise estimation of the catching distance is accomplished binocularly, based on some type of triangulation mechanism.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00298120
