Subscription required: In Science Magazine
Perspective Neuroscience The Mood of a Worm by Scott W. Emmons
Science 26 October 2012: 475-476.
Excerpt: “On pages 540 and 543 in this issue, Garrison et al. (1) and Beets et al. (2), respectively, add to a growing body of evidence that even at the highest levels of coordinating fundamental and complex behaviors, the same neural mechanisms are at work in worms and humans. ”
My comment: The yeast mating pheromone activates mammalian gonadotrophs and there are downstream effects on luteinizing hormone (LH) of a similar molecule called gonadotropin releasing hormone (GnRH), which is conserved across approximately 400 million years of vertebrate evolution. GnRH is also essential to both HPG axis and HPA axis regulation. This suggests that the epigenetic effects of nutrient chemicals and species-specific pheromones on the control of adaptive evolution by GnRH precede any effect of hormones like oxytocin or vasopressin on the development of mammalian behavior.
So far as I know, a molecule similar to GnRH is essential to nutrient chemical-dependent and pheromone-controlled reproduction in all species, including C. elegans. If oxytocin and vasopressin are equally important to adaptive evolution, can we anticipate that their secretion is also directly effected by nutrient chemicals or pheromones. If not, they must play a decidedly reduced role in adaptive evolution of social and sexual behaviors in species from worms to mammals. Indeed, the role of GnRH can be linked via olfaction and odor receptors to a clear evolutionary trail that can be followed from unicellular organisms to insects to humans — one that is exemplified in the honeybee model organism. Given any consideration for adaptive evolution via ecological, social, neurogenic, and socio-cognitive niche construction, it is difficult for me to conceive of any crucial role for oxytocin and vasopressin
except as secondary to the role of GnRH and its receptor diversification.