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Behavioral patterns and their underlying mechanisms can be examined from a hierarchy of levels—ethological, morphological, and physiological, in order to gain a better understanding of trait evolution and organismal design. Constriction, a prey handling method, has been associated with the adaptive radiation of snakes and is a behavioral homology for the majority of snake taxa. Constriction postures vary among lineages but phylogenetic variation in the epaxial motor patterns underlying constriction remains unknown. I tested how prey restraint behavior and coil application differed between basal and intermediate snake taxa and whether the underlying physiology could be linked to the behavioral differences observed. I specifically focused on basal and intermediate snakes as experimental studies for these lineages are lacking. I found that the ability to vary prey restraint behavior in response to prey characteristics and the application of loops laterally around prey are most probably the ancestral condition in snakes. Intermediate taxa, such as boas, exhibit a derived simplified behavioral repertoire. I then tested whether the underlying physiological patterns of constriction corresponded with the variability of loop application patterns documented. Using electrophysiological techniques, I comparatively examined epaxial muscle activity patterns during constriction for basal and intermediate snake lineages to determine whether the underlying physiological mechanisms of constriction corresponds to the postural changes observed at the behavioral level. Lateral bending and unilateral muscle activity patterns were predominant in the basal lineage, Loxocemidae. Lateral bending and unilateral muscle activity were also observed in derived snake taxa (Colubridae) previously documented. Ventral bending and bilateral epaxial muscle activity patterns were predominant in intermediate lineages (Boidae and Pythonidae) and present in derived snake lineages. The variation in the underlying muscle activity patterns during constriction correspond with variation at the ethological level. Thus the diversity of muscle activity patterns underlying prey restraint behavior can be correlated with differences in prey restraint postures.