Re: "It is tempting to speculate that certain ORs or variants of ORs influence dietary selection. These ORs might be selected during human evolution based on the available food source in a given habitat."

I recently addressed this speculation with a model of nutrient chemical calibration of individual survival where the nutrient chemicals are metabolized to pheromones that standardize and control reproduction and species survival.

This occurs in species from microbes to man, but is best detailed using the honeybee model organism and what is currently known about the molecular biology, which allows the epigenetic effects of nutrient chemicals and pheromones to be the primary determining factors for species survival (i.e., not random mutations).

As suggested by these authors, nutrient chemicals establish the ecological niches, which establish the social niches. In vertebrates the social niches are linked to neurogenic niches in the hypothalamus that alter luteinizing hormone, olfactory bulb neurogenesis and hippocampal neurogenesis, learning and memory.

Of course, because I've dismissed any evolutionary theory involving random mutations, my work has been largely ignored to date, so it is nice to see others speculate about what I have modeled across species from microbes to man. Perhaps now someone will offer an alternative comprehensive model of individual and species survival based on what's known about current molecular biology.

Kohl, J.V. (2012) Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors. Socioaffective Neuroscience & Psychology, 2: 17338.
http://dx.doi.org/10.3402...

See also: Jones et al (2012) The genomic basis of adaptive evolution in threespine sticklebacks. Nature, 484, 7392:55-61