Generalization in response to mate recognition signals.
Females usually exhibit strong and unequivocal recognition of conspecific mating signals and reject those of other sympatric heterospecifics. However, most species are allopatric with one another, and the degree to which females recognize mating signals of allopatric species is more varied. Such mating signals are often rejected but are sometimes falsely recognized as conspecific. We studied the dynamics of mate recognition in female túngara frogs (Physalaemus pustulosus) in response to a series of calls that were intermediate between the conspecific and each of five allopatric-heterospecific calls: two that elicited recognition from females in previous studies and three that did not. This study shows that females perceive variation in allopatric mating signals in acontinuous manner with no evidence of perceptual category formation. The strength of recognition is predicted by how different the target stimulus is from the conspecific call within a series of calls. But the differences in recognition responses among call series are not predicted by the similarity of the call series to the conspecific call. The latter result suggests that the strength of recognition of allopatric signals might be influenced by processes of stimulus generalization and past evolutionary history.
Ryan
Michael J
MJ
Section of Integrative Biology C0930, University of Texas, Austin, Texas 78712, USA. mryan@mail.utexas.edu
Rand
William
W
Hurd
Peter L
PL
Phelps
Steve M
SM
Rand
A Stanley
AS
D000161:Acoustic Stimulation; D000818:Animals; D001001:Anura / Q000502:physiology*; D005260:Female; D006309:Hearing / Q000502:physiology; D008297:Male; D009043:Motor Activity; D012726:Sexual Behavior, Animal; D013045:Species Specificity; D014828:Vocalization, Animal