Biology subjects

Masly, J. P.

Publications and source records attributed to Masly, J. P..

2 recordsLinked to original sources

bioRxiv2018

Quantitative variation in female sensory structures supports species recognition and intraspecific mate choice functions in damselflies

Males and females exchange signals prior to mating that convey information such as sex, species identity, or individual condition. Tactile signals relayed during physical contact between males and females before and during mating appear to be important for mate choice and reproductive isolation in some animals. However, compared to our understanding of visual, auditory, and chemical signals, we know little about the importance of tactile signals in mating decisions. Among North American damselflies in the genus Enallagma (Odonata: Coenagrionidae) species-specific tactile stimulation contributes to reproductive isolation between species and may also be important for intraspecific mate choice. We quantified several mechanosensory sensilla phenotypes on the female thorax among multiple sympatric and allopatric populations of two Enallagma species that occasionally interbreed in nature. Although each species differed in features of sensilla distribution within the thoracic plates, we found no strong evidence of reproductive character displacement among the sensilla traits we measured in regions of sympatry. However, substantial variation of sensilla traits was observed within populations of both species. Our results suggest that species-specific placement of female mechanoreceptors appears sufficient for species recognition, but mechanosensor variation among females within species may be important for mate choice.

evolutionary biology↗

bioRxiv2017

Mechanical And Tactile Incompatibilities Cause Reproductive Isolation Between Two Young Damselfly Species

External male reproductive structures have received considerable attention as an early-acting cause of reproductive isolation (RI), because the morphology of these structures often evolves rapidly between populations. This presents the potential for mechanical incompatibilities with heterospecific female structures during mating and could thus prevent interbreeding between nascent species. Although such mechanical incompatibilities have received little empirical support as a common cause of RI, the potential for mismatch of reproductive structures to cause RI due to incompatible species-specific tactile cues has not been tested. We tested the importance of mechanical and tactile incompatibilities in RI between Enallagma anna and E. carunculatum, two damselfly species that diverged within the past ~250,000 years and currently hybridize in a sympatric region. We quantified 19 prezygotic and postzygotic RI barriers using both naturally occurring and lab-reared damselflies. We found incomplete mechanical isolation between the two pure species and between hybrid males and pure species females. Interestingly, where mechanical isolation was incomplete, females showed greater resistance and refusal to mate with hybrid or heterospecific males compared to conspecific males, which suggests that tactile incompatibilities involving male reproductive structures can influence female mating decisions and form a strong barrier to gene flow in early stages of speciation.

evolutionary biology↗