Giorgio M. Innocenti - Böcker

Of the three organizers of this NATO Advanced Research Workshop on "Neocortex: Onto- geny and Phylogeny", one derived most of his knowledge about neocortex from studies on birds, another had never studied any animal but the cat and could probably recognize not more than ten animal species, and the third had very limited experience with mountaineering. They had in common the belief that evolutionary thinking permeates what biologists do, but that evolution of species and structures cannot be directly experimentally addressed. Although the fossil record can provide some major insights, the inroad to the evolution of the brain is indirect, via comparative anatomy and developmental biology. By identifying similarities and differences between brain structures in the species at hand, comparative anatomy generates hypotheses of evolutionary transformations. By understanding the rules of morphological transformation, developmental biology can, in principle, estimate the likelihood that a given transformation may have actually occurred. The meeting was a way to check if this notion is viable, by gathering together scientists from these two fields. Standing, left to right: F. Ebner, V.Caviness, M. Weisskopf, B. Fritszch, N. Swindale, J. Walter, H. Karten, J. Pettigrew, E. Welker, M. Cynader, D. Frost, L. Lopez-Mascaraque, P. Katz, H. Jerison, E. Soriano, Mayor of Alagna, Dr. G. Guglielmina, and associate, H. Van der Loos, B. Finlay, H. Scheich, C. Ruela. Seated: S. Pallas, T. Lohmann, J. De Carlos, F. Valverde, G. Innocenti, M. Diamond v "Gathering" does not accurately describe what really happened.

It is appropriate at the outset of this book to pose a question that was often asked --of the organizers before the meeting took place and later among those who participated in the meeting -- "What is meant by 'Systems Approaches' in the study of developmental neurobiology?" The answer, as we originally conceived it, can be succinctly summarized by the word "interactions". That brief epithet was expanded during the general discussion portion of the meeting, where the following definition was offered: "Systems approaches in developmental neurobiology are unified by attention to the emergent properties of the developing system under investigation and by a focus on the aspects of development of the nervous system that depend on interactions among its various elements, be they molecular, intracellular or multicellular. " As opposed to ignoring complexity or trying to wish it away, those of us who utilize a systems approach embrace the principle that complexity is what makes the nervous system special. We have come to recognize that wherever we look, we find interactions which are to be probed and eventually. understood. Even the so-called "simple systems", a term that has been used to describe many invertebrate preparations, are embraced under the above definition, since with further study it is becoming increasing clear that such systems are not as simple as once thought. We also include molecular genetics under the systems rubric. After all, genes regulate other genes which regulate others, and so it goes.