In the genus Panorpa （Insecta： Mecoptera）, also known as scorpionflies, pre- mating behavior includes repeated sequences of slow wing movements （waving, fanning, flagging） which are accompanied by rapid abdomen v...In the genus Panorpa （Insecta： Mecoptera）, also known as scorpionflies, pre- mating behavior includes repeated sequences of slow wing movements （waving, fanning, flagging） which are accompanied by rapid abdomen vibrations that generate substantial substrate-borne sound. It is still unknown whether wing patterns or vibratory signals contain information about species identity, sex and/or the quality of potential mating part- ners. Besides species-specific pheromones, these multimodal signals may be of particular importance for the maintenance of reproductive isolation in sympatrically occurring scor- pionfly species. Here, we analyzed phyologenetic relationships among, and the pattern of forewings as well as substrate-borne sound in 3 different sympatric Central-European scorpionfly species （P communis, P germanica, and P alpina）. Divergence time estimates, based on 879 bp of the mitochondrial COI gene, indicate longstanding separate evolu- tionary histories for the studied Panorpa species. Morphological analysis revealed that wing length as an indicator of body size increased in the following order： P alpina 〈 P. germanica 〈 P. communis. Individuals can be assigned to the correct species and sex with high accuracy just by evaluation of the number of dark spots and the proportion of wing pigmentation. Despite high variability of interpulse period at an individual level, across species analysis revealed a positive correlation of average interpulse period as well as mean signal amplitude with forewing length. These results suggest wing patterns, but less likely vibratory signals, to contain information about species identity. Furthermore, receivers may be able to estimate the body size of a signaler solely on the basis of substrate-borne sound.展开更多
Premating reproductive isolation （RI） may reduce gene flow across populations that have differentiated in traits important for mate choice. Examining RI across genetic and phenotypic clines can inform the fundamenta...Premating reproductive isolation （RI） may reduce gene flow across populations that have differentiated in traits important for mate choice. Examining RI across genetic and phenotypic clines can inform the fundamental evolutionary processes that underlie population and lineage differentiation. We conducted female mate-choice studies across an intraspecific red-eyed treefrog cline in Costa Rica and Panama with 2 specific aims： （1） to characterize RI across the cline and examine the relationship between premating RI and genetic and phenotypic distance and （2） to evaluate our results within a broader evolutionary and taxonomic perspective through examination of other RI studies. We found that female red-eyed treefrogs prefer local males relative to non-local males, indicating that some premating RI has evolved in this system, but that preference strength is not associated with phenotypic or geographic distance. Our analysis of 65 other studies revealed no clear pattern between the strength of RI and geographic distribution （allopatry, parapatry, cline） or phenotypic distance, but revealed extreme variation and overlap in levels of intra- and interspecific levels of RI. This work contributes to a growing body of literature that examines intraspecific RI across a cline to understand the selective processes that shape evolutionary patterns at the earliest stages of divergence.展开更多
文摘In the genus Panorpa （Insecta： Mecoptera）, also known as scorpionflies, pre- mating behavior includes repeated sequences of slow wing movements （waving, fanning, flagging） which are accompanied by rapid abdomen vibrations that generate substantial substrate-borne sound. It is still unknown whether wing patterns or vibratory signals contain information about species identity, sex and/or the quality of potential mating part- ners. Besides species-specific pheromones, these multimodal signals may be of particular importance for the maintenance of reproductive isolation in sympatrically occurring scor- pionfly species. Here, we analyzed phyologenetic relationships among, and the pattern of forewings as well as substrate-borne sound in 3 different sympatric Central-European scorpionfly species （P communis, P germanica, and P alpina）. Divergence time estimates, based on 879 bp of the mitochondrial COI gene, indicate longstanding separate evolu- tionary histories for the studied Panorpa species. Morphological analysis revealed that wing length as an indicator of body size increased in the following order： P alpina 〈 P. germanica 〈 P. communis. Individuals can be assigned to the correct species and sex with high accuracy just by evaluation of the number of dark spots and the proportion of wing pigmentation. Despite high variability of interpulse period at an individual level, across species analysis revealed a positive correlation of average interpulse period as well as mean signal amplitude with forewing length. These results suggest wing patterns, but less likely vibratory signals, to contain information about species identity. Furthermore, receivers may be able to estimate the body size of a signaler solely on the basis of substrate-borne sound.
文摘Premating reproductive isolation （RI） may reduce gene flow across populations that have differentiated in traits important for mate choice. Examining RI across genetic and phenotypic clines can inform the fundamental evolutionary processes that underlie population and lineage differentiation. We conducted female mate-choice studies across an intraspecific red-eyed treefrog cline in Costa Rica and Panama with 2 specific aims： （1） to characterize RI across the cline and examine the relationship between premating RI and genetic and phenotypic distance and （2） to evaluate our results within a broader evolutionary and taxonomic perspective through examination of other RI studies. We found that female red-eyed treefrogs prefer local males relative to non-local males, indicating that some premating RI has evolved in this system, but that preference strength is not associated with phenotypic or geographic distance. Our analysis of 65 other studies revealed no clear pattern between the strength of RI and geographic distribution （allopatry, parapatry, cline） or phenotypic distance, but revealed extreme variation and overlap in levels of intra- and interspecific levels of RI. This work contributes to a growing body of literature that examines intraspecific RI across a cline to understand the selective processes that shape evolutionary patterns at the earliest stages of divergence.
