Rapid speciation via the evolution of pre-mating isolation in the Iberá Seedeater

TURBEK, SHEELA P.; BROWNE, MELANIE; DI GIACOMO, ADRIÁN S.; KOPUCHIAN, CECILIA; HOCHACHKA, WESLEY M.; ESTALLES, CECILIA; LIJTMAER, DARÍO A.; TUBARO, PABLO L.; SILVEIRA, LUÍS FÁBIO; LOVETTE, IRBY J.; SAFRAN, REBECCA J.; TAYLOR, SCOTT A.; CAMPAGNA, LEONARDO

SCIENCE

AMER ASSOC ADVANCEMENT SCIENCE

Año: 2021 vol. 371

0036-8075

Behavioral isolation can catalyze speciation and permit the slow accumulation of additional reproductivebarriers between co-occurring organisms. We illustrate how this process occurs by examining the genomicand behavioral bases of pre-mating isolation between two bird species (Sporophila hypoxantha and therecently discovered S. iberaensis) that belong to the southern capuchino seedeaters, a recent, rapid radiationcharacterized by variation in male plumage coloration and song. Although these two species co-occurwithout obvious ecological barriers to reproduction, we document behaviors indicating species recognitionby song and plumage traits and strong assortative mating associated with genomic regions underlying maleplumage patterning. Plumage differentiation likely originated through the reassembly of standing geneticvariation, indicating how novel sexual signals may quickly arise and maintain species boundaries.