These authors contributed equally to this work.
Rapid evolution of sexual signals in sympatric Calopteryx damselflies: reinforcement or ‘noisy-neighbour’ ecological character displacement?
Article first published online: 20 APR 2007
Journal of Evolutionary Biology
Volume 20, Issue 4, pages 1637–1648, July 2007
How to Cite
MULLEN, S. P. and ANDRÉS, J. A. (2007), Rapid evolution of sexual signals in sympatric Calopteryx damselflies: reinforcement or ‘noisy-neighbour’ ecological character displacement?. Journal of Evolutionary Biology, 20: 1637–1648. doi: 10.1111/j.1420-9101.2007.01297.x
- Issue published online: 20 APR 2007
- Article first published online: 20 APR 2007
- Received 29 August 2006; revised 8 November 2006; accepted 17 November 2006
- enhanced isolation;
- reproductive character displacement;
Enhanced prezygotic isolation in sympatry is one of the most intriguing patterns in evolutionary biology and has frequently been interpreted as evidence for reinforcement. However, the frequency with which reinforcement actually completes speciation remains unclear. The Jewelwing damselflies (Calopteryx aequabilis and C. maculata) have served as one of the few classic examples of speciation via reinforcement outside of Drosophila. Although evidence for wing pattern displacement and increased mate discrimination in this system have been demonstrated, the degree of hybridization and gene flow in nature are unknown. Here, we show that sympatric populations of these two species are the result of recent secondary contact, as predicted under a model of speciation via reinforcement. However, we found no phenotypic evidence of hybridization in natural populations and a complete association between species-specific haplotypes at two different loci (mitochondrial CO I and nuclear EF1-α), suggesting little or no contemporary gene flow. Moreover, genealogical and coalescent-based estimates of divergence times and migration rates indicate that, speciation occurred in the distant past. The rapid evolution of wing colour in sympatry is recent, therefore, relative to speciation and seems to be better explained by selection against wasting mating effort and/or interspecific aggression resulting from a ‘noisy neighbour’ signalling environment.