03024nas a2200265   4500008004100000245014600041210006900187520194300256653002702199653002502226653001702251653001802268653004002286653001502326100002002341700001902361700002002380700001802400700001702418700002102435700002502456700002302481700001602504856023802520       2019                        eng d00aVocal divergence is concordant with genomic evidence for strong reproductive isolation in grasshopper mice ( <i>Onychomys</i>               )0 aVocal divergence is concordant with genomic evidence for strong 3 a<p>Behavioral barriers to gene flow often evolve faster than intrinsic incompatibilities and can eliminate the opportunity for hybridization between interfertile species. While acoustic signal divergence is a common driver of premating isolation in birds and in‐ sects, its contribution to speciation in mammals is less studied. Here we characterize the incidence of, and potential barriers to, hybridization among three closely related species of grasshopper mice (genus Onychomys). All three species use long‐distance acoustic signals to attract and localize mates; Onychomys arenicola and Onychomys torridus are acoustically similar and morphologically cryptic whereas Onychomys leu‐ cogaster is larger and acoustically distinct. We used genotyping‐by‐sequencing (GBS) to test for evidence of introgression in 227 mice from allopatric and sympatric lo‐ calities in the western United States and northern Mexico. We conducted laboratory mating trials for all species pairs to assess reproductive compatibility, and recorded vocalizations from O. arenicola and O. torridus in sympatry and allopatry to test for evidence of acoustic character displacement. Hybridization was rare in nature and, contrary to prior evidence for O. torridus/O. arenicola hybrids, only involved O. leu‐ cogaster and O. arenicola. In contrast, laboratory crosses between O. torridus and O. arenicola produced litters whereas O. leucogaster and O. arenicola crosses did not. Call fundamental frequency in O. torridus and O. arenicola was indistinguishable in allopatry but significantly differentiated in sympatry, a pattern consistent with repro‐ ductive character displacement. These results suggest that assortative mating based on a long‐distance signal is an important isolating mechanism between O. torridus and O. arenicola and highlight the importance of behavioral barriers in determining the permeability of species boundaries.</p>
10aacoustic communication10abehavioral isolation10acontact zone10ahybridization10areproductive character displacement10aspeciation1 aCampbell, Polly1 aArévalo, Lena1 aMartin, Heather1 aChen, Charles1 aSun, Shuzhen1 aRowe, Ashlee, H.1 aWebster, Michael, S.1 aSearle, Jeremy, B.1 aPasch, Bret  uhttps://onlinelibrary.wiley.com/doi/abs/10.1002/ece3.5770https://onlinelibrary.wiley.com/doi/pdf/10.1002/ece3.5770https://onlinelibrary.wiley.com/doi/pdf/10.1002/ece3.5770https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ece3.5770