I’ve seen a video discussing actual research done in MS with captive deer sourced from both the middle Delta/AG region and lower coastal plain pine county which tracked weight and alter mass gains when placed into a situation with over abundance of highly nutritious food and no pressure over three generations. The gains from the delta deer were noticeable but the improvement to the lcp deer were phenomenal. Local genetics can still factor in regardless of nutrition, though. The deer in my area of Monroe county, overwhelmingly, display the same, consistent asymmetrical racks which favor the same side across generation. I have about 40 years of racks hanging around the camp that display the same wonky curve regardless of age or antler size.