Francis Balfour : A Prodigy Dies Young (2006.2.1[Wed])

 

What developmental biologist doesn't feel a twinge of regret at the mention of the name Balfour (Francis Maitland Balfour, 1851-1882). We can only wonder what he might have achieved in the field if he hadn't lost his life in a climbing accident in the Swiss Alps in his early 30s. In his all too short career, he authored a pair of works of indispensable importance to my own field of research; the timeless "A Monograph on the Development of the Elasmobranch Fishes" (1878), and the 2-volume "A Treatise on Comparative Embryology" (1885), a copy of which graces the CDB rare book collection. Balfour was rightly regarded in his day as the legitimate heir to the tradition of comparative embryology founded by Von Baer. Those interested in a fuller account of his life and achievements are referred to either Hall BK. "Francis Maitland Balfour (1851-1882): A Founder of Evolutionary Embryology." J Exp Zoolog B Mol Dev Biol or the relevant chapter in "Evolutionary Developmental Biology" (1998; available in Japanese translation), both authored by one of the opinion leaders of evolutionary developmental biology, Brian K. Hall. As I understand it, Dr. Hall is now engaged in writing a biography of Balfour, which should only serve to deepen our understanding and appreciation for this great figure.

 How was it possible for a scientist not even 30 to identify and successfully tackle several problems worthy of a veteran researcher seasoned by years of experience and hard-won insight? What environment could have fostered such a man? Looking at Balfo  ur's career, one can't help but wonder in a kind of awe. As an undergraduate, he demonstrated the homology of the amphibian blastopore and the avian primitive streak based on observations of morphology and tissue rearrangements. On graduation, he moved to the   Stazione Zoologica Napoli to work under Anton Dohrn, a disciple of the Haeckelian school. There, he not only published the first study of shark embryogenesis, but also discovered the fluid-filled mesodermal cavity within the elasmobranch head. These discoveries set the stage for questions into whether segmentation occurs in the head mesoderm, and more generally into the evolution of head patterning in vertebrates itself. Whether they profess an interest in evolution or not, developmental biologists around the world are still working today to unriddle these same questions, with any number of major journals eager to publish their findings. It was Balfour that laid the foundations for the framework of inquiry that made those investigations possible.

 But the real evidence of his prescient genius can be found in the preface to Hall's book, in which Balfour, still in his early 20s, is cited thus:

I see no reason for doubting that the embryo in the earliest periods of development is as subject to the laws of natural selection as is the animal at any other period.
Balfour (1874) A preliminary account of the development of the elasmobranch fishes. Quart. J. Microsc. Sci., 14, p.343

 There you have it. What he's saying is that changes in developmental patterns and processes can be assumed to take place equally at any stage, that there is no inherent necessity for patterns at the earliest stages of ontogeny to be more strictly conserved that those of later stages. Everything, every step of the way, is equally subject to natural selection. For all of the scientists out there today who say that the earlier you look in development, the easier it is to perform comparisons across taxa and from there to make the conjectural leap straight into homology, this should serve as a wake-up call. A mere 23-year old back in the last days of the 19th century freed himself from that thinking and made his way forged a path right to the very heart of comparative development before his own untimely end. From time to time, a man emerges of such genius as to make us reconsider the true meaning of the word.

Reference : ”A Treatise on Comparative Embryology”