How genetics, with the help of the humble fruit fly, moved into the forefront of modern science.
Brookes (Get a Grip on Genetics, not reviewed) begins where modern biology begins: with Darwin. But the father of evolution was, like his naturalist predecessors, an observer and collector rather than an experimenter. As the 19th century came to a close, a new generation of scientists champed at the bit, anxious to test their theories in the laboratory. As Thomas Hunt Morgan of Columbia University discovered, the fruit fly—short-lived, prolific, easy to raise in a bottle—was an ideal experimental subject. A few years later, his student Herman Muller learned that exposure to X-rays would bring about a rash of bizarre mutations in the flies: legs growing where antennae ought to, or doubled body segments. By the 1930s, this discovery had opened the door to the study of the individual genes responsible for the mutations, and new insight into the developmental patterns of growing organisms. The saliva glands of the fly contain oversized chromosomes that allow scientists to observe individual genes directly. The connection between genetics and evolution was reestablished by Theodosius Dobzhansky, whose studies of wild-fruit-fly populations pointed up the genetic diversity within a single species that is the raw material of evolutionary development. Later experiments with “jumping” genes led to the discovery of a rudimentary form of genetic engineering, of the genetic foundations of behavior, and hints of the secrets of longevity. Brookes gives enough detail of the various experiments to give the layperson a grasp of their significance, and provides an entertaining glimpse of the daily workings of a genetics lab.
A well-written and cohesive treatment of the fundamentals of genetics, as revealed through its favorite experimental subject.