Olfactory Orientation in Urodele Amphibians
摘要
The olfactory organ of Urodela amphibians appears to be a phylogenetically ancestral type for terrestrial vertebrates. Owing to their complex biphasic life cycle, these amphibians are an interesting object for studying olfactory orientation. The magnitude of movements of Urodela is not large; however, they can return to a breeding pond or home range from distances far exceeding natural movements. Olfaction potentially plays a significant role in this process. Laboratory experiments have shown the ability of newts and salamanders to discriminate between different odor sources: the water of breeding pond, shelters, and the scent marks of conspecifics. However, the results of field experiments which test directly the role of olfaction in the homing process are quite ambiguous. There are also still few data on natal philopatry and its mechanisms. It is not known whether Urodela have olfactory imprinting similar to that of fish and Anura, although some evidence supports the presence of imprinting. Further study of the olfactory orientation of Urodela will improve understanding of the evolution of this system in vertebrates and methods of conservation of amphibians.