The reprinting of this classic book provides students
with one of the few authoritative, analytical works
dealing with the early history of genetics. Those of
us who had the privilege of knowing and working with
Sturtevant benefited greatly from hearing first-hand
his accounts of that history as he knew it and, in
many instances, experienced it. Fortunately,
Sturtevant put it all together in this book.
In his preface to the book, Sturtevant lists the
persons that he knew personally and who were major
players in the field, in addition to those who
occupied the famous fly room (Chapter 7) at Columbia
University. As a result, much of the history is based
on first-hand contacts as well as on a scholarly and
critical review of the literature of genetics and
cytology.
Sturtevant was clearly present at the creation of
modern genetics, if dated from 1910 when Morgan
commenced work on Drosophila. Of Morgan’s three
students - Sturtevant, Bridges, and Muller -
Sturtevant was ideally suited to write the history
because of his remarkable memory, his knowledge of
almost all aspects of biology, and a keen analytical
ability that extended not only to his experimental
work, but also to tracing the history of the
underlying ideas.
Sturtevant was a gifted writer and also an authority
on many of the subjects he covers. While he was a
sophomore in college, he deduced the linear order of
the genes. Later, he postulated the existence of
inversions and duplications before they were verified
cytologically. Sturtevant was especially interested
in how genes produce their effects and, consequently,
was the father of a field now called developmental
genetics. In this area, his style was to analyze
exceptions to the rule. In so doing, he identified
the phenomenon of position effect, in which the
position of a gene (that of the Bar, and double-Bar,
eye mutations) can be shown to affect its function.
He identified the first clear case of a non-
autonomously expressed gene, vermilion, mutants of
which produce a vermilion, instead of the normal red,
eye color. This was an important exception to the
rule that sex-linked mutants behaved autonomously in
gynandromorphs. How this led to the field of
biochemical genetics is explained in Chapter 16.
In the tradition of such biologists as Darwin,
Galton, and Bateson and of many of the early
Mendelians, Sturtevant was an ardent evolutionist. He
had a seemingly inexhaustible knowledge of
embryology, anatomy, morphology, and taxonomy that
served him well in treating evolutionary concepts
historically, as described in Chapter 17. It is a
wide-ranging chapter that covers many topics,
including the development of population genetics, the
role of gene mutations in evolution, and,
prophetically, the conservation of biochemical
pathways in major groups from bacteria to
vertebrates. His own experimental work, typically
only briefly referred to, included his work on
interracial and interspecific hybrids in the genus
Drosophila, and the demonstration that the genetic
content of different species of that genus is
remarkably conserved, whether it be in the X
chromosome or in each of the specific autosomal arms.
Sturtevant always had a healthy skepticism, surely
one of the most important qualities of a successful
scientist. This is shown by his doubt of the value of
many laboratory experiments in population genetics,
on the basis that they cannot faithfully duplicate
what really goes on in the great out-of-doors.
It may come as a surprise to many students to realize
how much opposition there was in some quarters to the
early discoveries of the Morgan school. Sturtevant’s
account of such controversies is a recurrent theme of
this book, as it should be in a historical treatise.
Science has often been advanced by scientists who
questioned existing dogma and found it flawed. Or,
conversely, such dogma has probably in some cases
slowed progress for years. Would advances in genetics
have been more rapid had there not been the virtually
universal belief that genes were proteins, or that
development of an organism involved cytoplasmic
rather than nuclear heredity? Sturtevant does not
waste space speculating about such issues, but he
does discuss several cases in which progress was held
back because of failure to develop a satisfactory
terminology and symbolism.
Sturtevant had a strong social consciousness that
comes forth in Chapter 20. There he treats the
history of human genetics, stressing the difficulties
and pitfalls that plague studies in this field. He
devotes considerable space to an objective and
critical analysis of the so-called “nature vs.
nurture” question.
In the last chapter, Sturtevant discusses how
discoveries in science and particularly genetics tend
to come about. He addresses in his typically
analytical way the often-cited dictum: The time has
to be ripe for a discovery to be made and that when
that time comes someone is bound to make the
discovery. He concludes that this attitude greatly
oversimplifies what generally happens in science.
I believe Sturtevant’s writing of this book after his
retirement was one more intellectual exercise to
stave off boredom. He had reduced his experimental
work to an hour or so each day, and it must have been
more difficult to keep up with the expanding
literature of the field. His book is clearly a labor
of love and his personality shines through every
page.