Schematic of the Callithrix oxytocin receptor. Different colored residues indicate amino acid substitutions (subs) that are common among Callithrix, Saimiri, and Callicebus, shared by two of these genera, or unique to one genus, relative to representative primates from other major taxonomic groups (Homo, Macaca and Otolemur). The solid and dashed lines showing putative binding regions for the ring vs. tail portion of OT are adapted from (Gimpl and Fahrenholz, 2001). * Indicates a unique substitution in Callithrix in addition to a variable shared NWM substitution. ** indicates S368L substitution in Saguinus reported by (Vargas-Pinilla et al., 2015). Generated using Protter (Omasits et al., 2014).