studying the extended phenotype...,

NYTimes | The investigation of the genetics of behavior is a huge scientific enterprise, with great progress being made in a variety of species — roundworms, fruit flies, lab mice, sticklebacks. Dr. Hoekstra’s work is unusual in that it deals with a naturally occurring, complicated behavior in mammals that is important for survival. And it is significant that she has been able to separate that behavior into two modules controlled by separate and independent DNA regions — burrow length, and escape tunnels.

Dr. Bargmann said she was impressed at Dr. Hoekstra’s success in unpacking the behavior into modules, a result that adds to the likelihood of one day finding simple genetic controls underlying the mystifying diversity of natural behavior patterns. The extraordinary variety of animal body shapes, after all, has been found to grow out of a relatively few master control genes.

“I really believe that there are rules for behavior that go all the way back,” Dr. Bargmann said.

One component of Dr. Hoekstra’s success has been oddly low-tech: the kind of fast-hardening foam that can be purchased in a hardware store for home repair. It quickly produces an easily measured mold — behavior solidified.

Another important factor is as high-tech as tech gets. Decades ago the evolutionary biologist Richard Dawkins suggested that one could study the evolution and genetics of behavior just the way one studies the evolution of body shape: concentrate on what animals build — birds’s nests, beaver dams, termite mounds — and treat them like beak length or coat color. Writing before the development of enormously powerful technology for analyzing DNA, he regretted that his proposals were hypothetical.

They are hypothetical no longer.
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You always have to watch the NYTimes like a hawk. Its reporting of topics in "evolutionary biology" always dangerously skirts Big Don-ism. Any time you mix molecular biology with a nonsensical theory in a disturbing mess of facts and factoids, you run the risk of creating a narrative that will be opportunistically co-opted for knuckledragging political ends. If you're going to talk about molecular biology as evolutionary biology, it is important first and foremost, to establish the clear understanding that molecular biologists will be studying differences in burrowing behavior which are nutrient-dependent and pheromone-controlled via epigenetic effects on genetic predispositions - as these consistently express across species - from microbes to man.

THOSE - are genetic mechanisms of behavior.

Stupid, ignorant, political opportunists will instead leap to unfounded conclusions about IQ, aggression, and a host of other non-molecular, non-falsifiable narrative correlations suited to their own political agenda. 

Bad molecular biologists will lose track of the complex machinery under consideration and fall prey to darwinian nostrums relating the study of beak length and coat color "random mutation" as the cause of adaptive evolution. 

The smart money, symbiogenetically enlightened molecular biologists, will stay focused on the more compelling understanding that adaptive evolution is nutrient-dependent and pheromone-controlled through epigenetic feedback mechanisms within symbiotic cohorts, and that optimized and protracted symbiosis gives rise to speciation, not "red in tooth and claw" random mutation.