For Christmas I bought my wife a puppy – a 10-week old soft-coated wheaten terrier. Karol named her "Molly."
Molly joins our nearly 14-year-old beagle, Priscilla. Priscilla – or "P," as we usually call her – silently tolerates Molly, except when Molly approaches P’s food bowl. This gentle geriatric beagle growls like a lion if Molly gets within 18 inches of P’s food bowl. Molly (wisely) gets the message and backs away.
But both dogs peacefully share the same water bowl. No growling, no sniping, no complaints. Both dogs drink happily from the same bowl, oftentimes simultaneously.
Why? After all, water is just as essential for life as is food. Indeed, because a dog can live a good deal longer without a meal than he or she can live without water, water arguably is more important than food.
My hypothesis is that natural selection gave dogs an (unconscious) understanding of the margin.
If historically for wolves (and dogs) water was more readily available than food, as seems plausible, then there was less to be gained by a dog being genetically programmed to threaten physical violence if another dog shared his water than there was to be gained from threatening violence if another dog tried to share his food. Put differently, each available unit of food was worth more to wolves and early dogs than was each available, comparably sized unit of water. Hence, dogs’ genes are evolved to prompt them to be willing to spend more – risking life and limb by threatening violence – to protect a food source than they are programmed to spend to protect an equally sized source of water.
Of course, I could be barking up the wrong tree.
Apropos nothing: Priscilla the beagle shares a birthday with F. A. Hayek, May 8th.