Evolution of a Secondary Sexual Dimorphism in the Toad, Bufo marinus

  title={Evolution of a Secondary Sexual Dimorphism in the Toad, Bufo marinus},
  author={Julian C. Lee},
  pages={928 - 935}
Abstract Adult females of the toad Bufo marinus significantly exceed adult males in snout–vent length (SVL), but at any SVL, adult males greatly exceed adult females in the robustness of the forelimbs. Secondary sexual shape dimorphism results from greater size and mass of the skeletal elements of males, and especially from their hypertrophied forelimb musculature. The dimorphism is particularly pronounced for those elements of the musculo-skeletal apparatus known or presumed to function in… 

Sexual Dimorphism, Growth, and Longevity of Two Toad Species (Anura, Bufonidae) in a Neotropical Savanna

Investigation of sexual dimorphism in body size and shape, growth, and longevity of two toad species, Rhinella rubescens and R. schneideri in the Cerrado of central Brazil suggests differences between the two species likely reflect their separation into two morphologically and phylogenetically distinct sister clades.

Sexual dimorphism in the limb muscles of the dark-spotted frog, Pelophylax nigromaculata

Sexual dimorphism in Pelophylax nigromaculata was investigated and it was found that three forelimb muscles involved in axillary amplexus were heavier in males compared to females, whereas five forelimB muscles not involved inAxillaryAmplexus showed no sexual differences in muscle mass.

Sexual selection in cane toads Rhinella marina: A male's body size affects his success and his tactics

A male cane toad's body size affects both his ability to defeat rivals in physical struggles over females, and the criteria he uses when selecting potential mates, but the impacts of that selectivity depend upon the context in which mating occurs.

Sexual size and shape dimorphism in Turkish common toads (Bufo bufo Linnaeus 1758)

Results show SD in body size with females having larger body size, a trait related with fecundity and thus probably under sexual selection, consistent with previous studies of major of Anura and support a role for selection pressures acting differentially upon individuals from both sexes.

Sexual dimorphism and age of Mediterranean salamanders.

Sexual Selection and Larval Performance of Two Species of Red-Eyed Treefrogs, Agalychnis callidryas and A. moreletii of the Chiquibul Forest Reserve, Belize.

The hypothesis that female mating preferences result in enhanced performance of their larvae, owing to genetic variation among sires in two species of red-eyed treefrogs is tested and a link between female preference for male traits and enhanced offspring performance by larvae sired by preferred males in the evolution of anuran mating systems is provided.

Sexual size and shape dimorphism in the Wushan salamander, Liua shihi (Liu, 1950) (Urodela: Hynobiidae)

It is proposed that sexual dimorphism of body size can be attributed to sexual selection and local climates, that AGS may contribute to fecundity selection, and that limb size may be beneficial for reproductive success.

Intersexual differences in body shape and locomotor performance in the aquatic frog, Xenopus tropicalis

Xenopus tropicalis frogs are used to test for intersexual differences in body size, body shape and locomotor performance traits and it is shown that females are larger than males, but that males have relatively longer limbs and heads than females.

No sexual dimorphism in limb muscles of a frog not engaging in amplexus

This work detected non-significant sexual differences in the mass of both forelimb and hindlimb muscles after accounting for body size and age in Feirana taihangnicus: a species without amplexus, an interesting example of coevolution of form and function.



Sexually dimorphic muscles in the forelimb of the Japanese toad, Bufo japonicus

Results suggest that the “sexually dimorphic muscles” are used especially for clasping by the male and are degenerative or subnormal in the female, and may well be necessary for tonic and prolonged contractions of the forelimb muscles during clasping.

The social behaviour of anuran amphibians

A biomechanical perspective on the use of forelimb length as a measure of sexual selection in frogs

The relevance of functional analysis to current questions in evolutionary biology that rely on postulated roles for morphological structures under selection is highlighted, such as lever arm lengths, that should influence amplexing ability and may make measures of overall forelimb length misleading.

Biology of Amphibians

This chapter discusses the origins and status of the lissamphibia cytogenetic, molecular and genomic evolution - cytogenetics, molecular evolution, genomic evolution phylogeny, and the evolutionary significance of metamorphosis.


No results obtained support of the existence of mate choice in either males or females.


  • A. Meyer
  • Biology, Environmental Science
    Evolution; international journal of organic evolution
  • 1987
The influence of diet on trophic morphology during ontogeny in Cichlasoma managuense was examined and two groups of full siblings were fed two different diets for eight months after the onset of feeding; thereafter both groups were fed a common diet.

Accuracy and Precision in Anuran Morphometrics: Artifacts of Preservation

The assumption that preservation induces tolerably little morphological distortion in frogs appears to be substantially violated, but an unknown proportion of among-group character variation may be attributable to measurer bias.

The Descent of Man, and Selection in Relation to Sex

Part II. Sexual Selection (continued): 12. Secondary sexual characters of fishes, amphibians and reptiles 13. Secondary sexual characters of birds 14. Birds (continued) 15. Birds (continued) 16.

Unilateral Activity and Bone and Muscle Development in the Forearm

Abstract Comparisons of external anthropometric and roentgenogram measurements between the arms of tennis players and soldiers revealed that tennis playing leads to muscular hypertrophy and to an