In In Pursuit of the Gene: From Darwin to DNA, James Schwartz aims to recount the history of genetics through the biographies of the principal researchers who advanced (and sometimes held back) the theory's development. The result is a highly readable work with something of the character of a soap opera about it. Rather than dusting off some ancient lab equipment and taking the reader through a technical account of the major experimental steps in the development of genetics, Schwartz has turned to the personal correspondence of the (mostly) men involved, to reveal the personal relationships between competing and collaborating researchers. It is this that lends the soap opera character to his narrative, for as Schwartz remarks "the early geneticists were a particularly passionate group, pathologically competitive in some instances and utterly selfless in others, prone to intense loyalties as well as overwhelming hatreds, singularly idealistic and ruthlessly pragmatic." (x) No daytime TV producer could hope for a cast of characters more likely to 'mix it up' with all manner of plot and intrigue.
The main narrative thread follows the search for the mechanism of heredity. Darwin's brilliant introduction of the notions of common descent and natural selection into biology had this one major oversight: while it was clear that the traits of an organism were passed on and that this explained the differential success of different organisms, the nature of the unit of heredity and how exactly it worked were unknown in Darwin's day. Although Darwin would not live to see it, the discrete nature of the unit had been demonstrated by Gregor Mendel just six years after the publication of The Origin of the Species, though it would take until early 1900 for Mendel's work to have an impact on the scientific discussion. Darwin's own attempt to address the problem, the theory of pangenesis, was a large step in the wrong direction. The theory of pangenesis was founded on the assumption that offspring are a blend of each parent's traits, but this clearly would have the consequence that variation over time disappears, since each generation 'averages out' the distinctiveness of the preceding generation and thus, tends to increasing sameness. In a fatal move, Darwin revived a Lamarkian notion of heritable acquired traits to supply the needed variation. Though both this and the 'blending hypothesis' would eventually prove mistakes, they would also have their champions in the subsequent search for a theory of heredity.
It may surprise some readers to learn of the intimate connection between the development of a theory of heredity and statistical methods. Darwin's cousin, Frances Galton, saw the possibility of applying the bell curve to inheritance, though his motive in this was the pursuit of his own dubious views on the improvement of the human mind through eugenics, the term itself having been introduced by Galton. Fortunately, it was the application of statistics that caught on among the next generation of biologists concerned with heredity, and major developments in both sciences followed from this relationship.
Galton's example presents a recurring pattern in Schwartz's narrative. Even while grinding his own idiosyncratic axe, Galton nevertheless made real advances and inspired others to take up the torch. What strikes the reader is how many of the early geneticists obsessively pressed their own peculiar (and mostly ill-fated) theories beyond any reason, and defended them in barely-polite intellectual combat against rivals. That any coherent theory arose out of this fray seems a wonder. But then, wonders do never cease, as it is said: in spite of their quirks, genuine contributions were made by these odd men.
The star example of the rivalries carried on must be Thomas Morgan's so-called 'fly room' at Columbia University. Many lay persons will recognize that fruit flies have something to do with genetics: here is the source. The basis of modern genetics came together in Morgan's lab, through breeding experiments on fruit flies conducted by a small collection of talented graduate students, including Alfred Sturtevant, Calvin Bridges and Hermann Muller. Despite the outward appearance of enthusiastic scientific collaboration, the fly room was the site of great strife and bad feeling over who was taking credit for group accomplishments, with Morgan himself seeming to be the principal culprit. The hostilities would reach the petty depths of trying to write each other out of history in memoirs. Despite attacks on his reputation, Muller would eventually win the Nobel Prize for artificially inducing mutations with X-rays.
For the reader more interested in the history of the science of genetics, In Pursuit of the Gene might be a disappointment. The science is there, of course, but thoroughly embedded in the human relationships of the scientists. Part of Schwartz's point in choosing this approach is to illustrate how personal the life sciences can become, with the directness of their implications for human life and relationships. This his book does very well. Galton, for example, seems to have come to his obsession with the heritability of genius shortly after failing in his attempt to become 'Cambridge Wrangler', the highest honor a Cambridge mathematics student can earn. It's not hard to imagine his scientific concerns as playing proxy for inner conflict.
© 2009 George Williamson
George Williamson, University of Saskatchewan