<p>by Matthew B. Frieman</p> Bat sarbecoviruses differ in the range of mammalian ACE2 receptors they can use, complicating predictions of spillover risk. Two new studies in PLOS Biology link receptor breadth with antigenic relatedness and reveal conserved spike epitopes targetable by antibodies. Bat sarbecoviruses differ in the range of mammalian ACE2 receptors they can use, complicating predictions of spillover risk. This Primer comments on two new studies in PLOS Biology that link receptor breadth with antigenic relatedness and reveal conserved spike epitopes targetable by antibodies.