Measuring and evaluating morphological asymmetry in fish: Distinct lateral dimorphism in the jaws of scale-eating cichlids

Hiroki Hata*, Masaki Yasugi, Yuichi Takeuchi, Satoshi Takahashi, Michio Hori

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

16 Scopus citations

Abstract

The left-right asymmetry of scale-eating Tanganyikan cichlids is described as a unilateral topographical shift of the quadratomandibular joints. This morphological laterality has a genetic basis and has therefore been used as a model for studying negative frequency-dependent selection and the resulting oscillation in frequencies of two genotypes, lefty and righty, in a population. This study aims were to confirm this laterality in Perissodus microlepis Boulenger and P. straeleni (Poll) and evaluate an appropriate method for measuring and testing the asymmetry. Left-right differences in the height of the mandible posterior ends (HMPE) and the angle between the neurocranium and vertebrae of P. microlepis and P. straeleni were measured on skeletal specimens. Snout-bending angle was also measured using a dorsal image of the same individuals following a previous method. To define which distribution model, fluctuating asymmetry (FA), directional asymmetry (DA), or antisymmetry (AS), best fit to the lateral asymmetry of the traits, we provided an R package, IASD. As a result, HMPE and neurocranium-vertebrae angle of both species were best fitted to AS, suggesting that P. microlepis and P. straeleni showed a distinct dimorphism in these traits, although snout-bending angle of P. microlepis was best fitted to FA. Measurement error was low for HMPE comparing the snout-bending angle in P. microlepis, indicating that measuring HMPE is a more accurate method. The scale-eating tribe Perissodini showed distinct antisymmetry in the jaw skeleton and neurocranium-vertebrae angle, and this laterality remains a valid marker for further evolutionary studies.

Original languageEnglish
Pages (from-to)4641-4647
Number of pages7
JournalEcology and Evolution
Volume3
Issue number14
DOIs
StatePublished - 2013/11

Keywords

  • Morphological laterality
  • Perissodus microlepis
  • Scale-eater
  • Tanganyikan cichlid

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Nature and Landscape Conservation

Fingerprint

Dive into the research topics of 'Measuring and evaluating morphological asymmetry in fish: Distinct lateral dimorphism in the jaws of scale-eating cichlids'. Together they form a unique fingerprint.

Cite this