Oxytocin/Vasopressin-Related Peptides Have an Ancient Role in Reproductive Behavior

Social Neuropeptides in Nematodes The neuropeptides oxytocin and vasopressin stimulate maternal, reproductive, aggressive, and affiliative behaviors in mammals. They are implicated in behaviors ranging from ewe-lamb bonding in sheep to pair bonding in voles (see the Perspective by Emmons ). Now, Garrison et al. (p. 540 ) and Beets et al. (p. 543 ) extend the evolutionary reach of these social neuropeptides to the invertebrate nematode worm, Caenorhabditis elegans . A similar neuropeptide was found to function in mating and also to modulate salt-taste preference, based on prior experience, suggesting an ancient role in associative learning.