Affordable Access

Evolution of the optical releasers for aggressive behavior in cave-dwelling Astyanax fasciatus (Teleostei, Characidae).

Authors
  • Langecker, T G
  • Neumann, B
  • Hausberg, C
  • Parzefall, J
Type
Published Article
Journal
Behavioural processes
Publication Date
Jul 01, 1995
Volume
34
Issue
2
Pages
161–167
Identifiers
PMID: 24897516
Source
Medline
License
Unknown

Abstract

Epigean and blind cave-dwelling populations of the characid Astyanax fasciatus differ in their agonistic behavior. Epigean specimens are characterized by intense aggressive behavior and territoriality in the laboratory, whereas the blind cave fishes are rarely aggressive and have totally lost the territorial behavior. These behavioral changes are genetically based. In the present study, a comparative analysis of the optical releasers for aggressive behavior has been performed in both epigean and cave-dwelling populations. It was expected that the regression of aggressive behavior should be accompanied by the regression of the genetically fixed optical releasers for aggression in the cave specimens. For the analysis of cave fishes, well-eyed F1-hybrids of cave and epigean specimens (Pachon × Teapao) as well as phylogenetically young cave specimens (Micos) selected for large eyes, have been used. In epigean specimens, aggression is most intensely released by a combination of the signals 'natural shape' and 'locomotion'. The cave populations exhibit a partial regression of the releaser 'natural shape'. 'Locomotion', however, has become a more effective releaser for aggression in cave fishes than it has in their epigean relatives. The results are discussed with respect to their evolutionary significance.

Report this publication

Statistics

Seen <100 times