Naturwissenschaften

, Volume 92, Issue 4, pp 188–192

Does testis weight decline towards the Subarctic? A case study on the common frog, Rana temporaria

  • Attila Hettyey
  • Anssi Laurila
  • Gábor Herczeg
  • K. Ingemar Jönsson
  • Tibor Kovács
  • Juha Merilä
Short Communication

DOI: 10.1007/s00114-005-0607-3

Cite this article as:
Hettyey, A., Laurila, A., Herczeg, G. et al. Naturwissenschaften (2005) 92: 188. doi:10.1007/s00114-005-0607-3

Abstract

Interpopulation comparisons of variation in resource availability and in allocation patterns along altitudinal and latitudinal gradients allow insights into the mechanisms shaping the life history of animals. Patterns of between-population differences in female life history traits have been studied intensively across a wide range of taxa, but similar investigations in males have remained scarce. To study if testis weight—a measure of reproductive investment—varies on a geographical scale in anurans, we focussed on the variation in relative testis weight (RelTW) and asymmetry in 22 populations of the common frog Rana temporaria along a 1,600-km latitudinal transect across the Scandinavian peninsula. We found that RelTW decreased towards the north. Body mass and body length both had independent positive effects on testes mass. We found evidence for directional asymmetry (DA) in testis weight with the right testis being larger than the left. The level of DA in testis weight was not related to latitude, but both body mass and testes mass had independent positive effects on asymmetry. We discuss the northwards decrease in RelTW in terms of a decreased reproductive investment as a possible consequence of harsher environmental conditions, and perhaps also, weaker sexual selection in the north than in the south.

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Attila Hettyey
    • 1
  • Anssi Laurila
    • 2
  • Gábor Herczeg
    • 1
  • K. Ingemar Jönsson
    • 3
  • Tibor Kovács
    • 1
  • Juha Merilä
    • 4
  1. 1.Behavioural Ecology Group, Department of Systematic Zoology and EcologyEötvös Loránd UniversityBudapestHungary
  2. 2.Department of Population Biology, Evolutionary Biology CentreUppsala UniversityNorbyvägen 18 dSweden
  3. 3.Department of Theoretical EcologyLund University, Ecology BuildingLundSweden
  4. 4.Ecological Genetics Research Unit, Department of Biological and Environmental SciencesUniversity of HelsinkiFinland