Tinbergen vs Dobzhansky
December 3, 2013 | James Kohl
Human Ethology Bulletin
Excerpt: As is now well-known, his view of ethology, “the biological study of behavior”, incorporated four interconnected strands – what causes a behavior, how does it develop, what is its functional significance, and how did it evolve.
He wrote: “… the only worthwhile biology is molecular biology. All else is “bird watching” or “butterfly collecting.” Bird watching and butterfly collecting are occupations manifestly unworthy of serious scientists!” (p. 443)
The challenge to Tinbergen (1963) and to other ethologists was clear. Instead of merely observing birds and/or collecting butterflies, Dobzhansky thought it was more important… “to discover just how the challenges of the environment are translated into evolutionary changes.”
In the past 5 decades, molecular biologists have discovered how the environment is translated into evolutionary change. Clearly, olfactory/pheromonal input causes the epigenetic landscape to become the physical landscape of DNA in the organized genomes of species from microbes to man. Adaptations occur that explain increasing organismal complexity via controlled nutrient-dependent pheromone-controlled ecological, social, neurogenic, and socio-cognitive niche construction. Conserved molecular mechanisms are involved at every level of biologically-based investigation that links the sensory environment to behavior via the gene-cell-tissue-organ-organ system pathway. Dobzhansky advocated including biophysical constraints and chemistry in “the biological study of behavior” instead of asking comparatively simple-minded what and how questions about observed behaviors.
Thus, what is known today about the biology of behavior can be attributed to Dobzhansky, but not to bird watchers. For example, we know that adaptations are nutrient-dependent and pheromone controlled. For comparison, the moderator of the International Society for Human Ethology‘s yahoo discussion group thinks that random mutations are the substrates on which directional natural selection acts.