Sexual ornaments, body morphology, and swimming performance in naturally hybridizing swordtails (teleostei: xiphophorus).

Sexual ornaments, body morphology, and swimming performance in naturally hybridizing swordtails (teleostei: xiphophorus).

Blog Article

Determining the costs of sexual ornaments is complicated by the fact that ornaments are often integrated with other, non-sexual traits, making it difficult to dissect the effect of ornaments independent of other aspects of the phenotype.Hybridization can produce reduced phenotypic integration, allowing one to evaluate performance across a broad range of multivariate trait values.Here we assess the relationship between morphology and performance in the swordtails Xiphophorus malinche and X.

birchmanni, two naturally-hybridizing Ringette Tip fish species that differ extensively in non-sexual as well as sexual traits.We took advantage of novel trait variation in Chifferobe hybrids to determine if sexual ornaments incur a cost in terms of locomotor ability.For both fast-start and endurance swimming, hybrids performed at least as well as the two parental species.

The sexually-dimorphic sword did not impair swimming performance per se.Rather, the sword negatively affected performance only when paired with a sub-optimal body shape.Studies seeking to quantify the costs of ornaments should consider that covariance with non-sexual traits may create the spurious appearance of costs.