Postdoc Jen Walsh authored a new paper in the Auk looking at the role of divergent mating strategies, reproductive success, and compatibility in maintaining the Saltmarsh-Nelson’s sparrow hybrid zone. Looking at nesting and paternity data for 342 sparrows of both pure and hybrid origin, she found that F1-F2 hybrid males exhibited significantly lower reproductive success compared to pure individuals and that Saltmarsh and Nelson’s sparrows exhibited strong patterns of assortative mating. These findings suggest that differences in mate choice and fitness in pure versus hybrid sparrows are important for maintaining pure species boundaries in this system.
Read the full paper here:
http://www.bioone.org/doi/10.1642/AUK-17-218.1