ScienceShot: Elephants Shaped Their Own Evolution by Elizabeth Norton on 26 June 2013, 1:00 PM
Excerpt: The finding suggests that the elephants tried out new feeding areas and new types of food, thus putting themselves in a position where natural selection would favor individuals with better-adapted teeth. By challenging the more passive view of natural selection—in which an environmental change simply favored elephants with stronger teeth—the study uses fossil evidence to show that the animals’ own behavior may have helped shape their evolutionary destiny.
My comment: Nutrient–dependent / pheromone–controlled adaptive evolution is exemplified in the context of ecological, social, neurogenic, and socio-cognitive niche construction, which is driven by the molecular mechanisms of epigenetic cause and effect (e.g., on the microRNA/messenger RNA balance). Changes in that balance lead to affects on behavior. Companion papers published last January discuss the mouse to human mammalian model in which a single nutrient-dependent amino acid change shows up in changes in teeth, skin, and hair in a population of modern humans that arose in what is now central China during the past ~30,000 years.
The nutrient-dependent changes in the teeth of elephants seem to have occurred over a much longer time. Perhaps their reproductive sexual behavior is not pheromone-controlled and their adaptive evolution occurred due to random mutations over millions of years, instead. However, there’s no model for that.
Kohl, JV (2013) Nutrient–dependent / pheromone–controlled adaptive evolution: a model
Socioaffective Neuroscience & Psychology, 3: 20553