The lie to that claim was given in a paper published online today in the Proceedings of the National Academy of Sciences of the United States of America (PNSA). A team of scientists from Japan, led by Teresa Romero of the Department of Cognitive and Behavioral Sciences, The University of Tokyo, Japan, in a beautifully simple experiment, showed that the hormone oxytocin increases the pair-bond between dogs and their masters.
Although the positive impact of social bonds on individual’s fitness has recently been demonstrated, the mechanisms underlying the motivation to form long-term associations remain largely unknown. Current evidence shows that oxytocin modulates social behavior but evidence of its effects in bond maintenance remains scant, especially in nonreproductive contexts. We provide evidence that in the domestic dog oxytocin enhances social motivation to approach and affiliate with conspecifics and human partners, which constitutes the basis for the formation of any stable social bond. Furthermore, endogenous oxytocin levels increased after dogs engaged in affiliation with their dog partners, indicating a stimulation of the oxytocin system during social interactions. Our findings highlight the important role that oxytocin has in the expression of sociality in mammals.
Social Sciences - Psychological and Cognitive Sciences:
Teresa Romero, Miho Nagasawa, Kazutaka Mogi, Toshikazu Hasegawa, and Takefumi Kikusui
Oxytocin promotes social bonding in dogs
PNAS 2014 ; published ahead of print June 9, 2014, doi:10.1073/pnas.1322868111
The researchers sprayed either a preparation of oxytocin or saline into the nostrils of sixteen dogs then allowed them back into a room where their owners were waiting. The owners had been instructed to ignore any social contact from their dog and did not know whether they had received oxytocin or saline. There was a statistically significant greater tendency for dogs to try to interact with their owners by licking, pawing and sniffing if they had received oxytocin than if they had received saline sprays.
Oxytocin is known to enhance pair-bonding between parents and offspring in many mammals and makes humans more trusting, cooperative and generous. This experiment also supports the theory that it may be involved in social interaction and friendship and will even act across species, especially where both species have a broadly similar social structure.
So, where does this leave our creationist friends' claim that somehow love can only be explained by God and exists in some spiritual, non-material realm, placing it outside the reaches of science and beyond human understanding? It leaves it where it always was: a nonsensical, evidence-free assertion that science has now shown to be false. Love is a physiological, biochemical response firmly in the realm of neurophysiology and psychology and so fully accessible to science and amenable to rational analysis and measurement.
And no less enjoyable for that.
Another gap closed and found not to be containing a god, of course.