George Happ

When I entered graduate school in 1958, the field of animal behavior was a disjointed amalgam of life history studies and psychology. I developed my first doctoral thesis proposal on "Hormonal Control of Reproductive Behavior of Wild Zebra Finches" and planned to pursue that project in the Laboratory of Ornithology at Cornell University.

But in the spring semester of my first year, I was converted to insect biology. I opted to work under Tom Eisner, a challenging young assistant professor whose research on insect chemical signals blended biology and chemistry in field and laboratory experiments that showcased adaptation and evolution.

As my own research interests progressed over subsequent decades, behavior led to cell biology, physiology, biochemistry, development, endocrinology, immunology, and zoonotic diseases. Now, my focus has now returned to bird behavior and the underlying neuroscience.

My consumate joy in retirement is the unstructured time to read diverse scientific literature available via the Internet. The advances in behavior and neuroscience since I received my doctorate are stunning.
In partnership with Christy Yuncker Happ, I follow the passing of the seasons in sub-Arctic Alaska, with particular attention to our wetland that has been owned for decades by Sandhill Cranes.

Sadly, in the 1920's and for decades thereafter, the dogmas of behaviorist psychologists belittled animal brains by interpreting animal behavior as merely readout of instinctive robotic brain mechanisms. Formal psychological theory and rigid terminology were contagious and spread to biology. In the 21^st century, the conceptual straight-jacket is gradually relaxing.

To understand the physiological bases of behavior, we must study the brain - the organ of cognition and consciousness. Higher mental processes are not unique to our species. By correlating disruption of behavior with known defects in brain circuits, one can discover many of the critical parts required for learning, emotion, etc. The next priority is to identify the mechanisms that enable circuits to interact. Evolutionary and comparative research offers attractive perspectives.

The brains of birds are particularly intriguing.

Avian and mammalian lineages split 300 million years ago. As their descendants acquired different life styles and body plans, their brains evolved in parallel. It has been argued that mammals and birds survived the K-T global cataclysm to become dominant on land today largely because each evolved a better brain.

How do bird and mammal brains differ? Both harken back to that of a crudely reptilian stem amniote. The divergence in bird and mammal brains, progressing over millenia, is broadly anlagous to geological Continental Drift. Nerve cell populations moved and were repackaged²and brain centers were repositioned³ as natural selection guided the adaptive trajectories in each line of descent.

In the light of emerging evidence from molecular embryology in this new century^2,3, we can begin to distinguish new adaptations from deeply shared legacies.

With luck and rigorous application of comparative biology, we might even discover new general principles of brain function: some persisting by common descent, some acquired by convergence, and some unique to a particular lineage.

¹ Darwin, C (1872). The Expression of Emotions in Man and Animals.
² Dugas-Ford J, Rowell JJ & Radsdale CW ( 2012). PNAS 109:16974-16979.
³ Jarvis ED, Güntürkün O ...... Reiner A & Butler AB (2005). Nat Rev Neurosci 6:151-159.