Bryan Clarke

Environmental factors affecting the quantity of alcohol dehydrogenase in Drosophila melanogaster

THE alcohol dehydrogenase gene in Drosophila melanogaster has recently been the subject of intense study because it has properties that make it almost ideal for the investigation of genetic fine structure and control in a higher eukaryote1–3, and for research on the population genetics of enzyme polymorphism4,5. There have been reports of genetic variation in alcohol dehydrogenase activity within and between electromorphs5–10, and of a putative control mutant with half the ‘normal’ activity11. The studies described here show that environmental factors can change the amount of ADH protein in a fly by at least fourfold. They invalidate conventional methods of correcting for body size in studies of the activities and amounts of enzymes in Drosophila, and therefore cast doubt on much recent work. They also raise the possibility of an inducible eukaryotic enzyme that is suitable for refined genetic analysis.

Natural Selection and the Evolution of Proteins

Jukes and King1 have attacked my article2. They do not quote my published criticism of their arguments3. Many of the points are discussed therein, and so a detailed reply is hardly necessary. They do, however, raise one additional matter of importance. They maintain that a selectionist hypothesis would predict radical changes to be favoured over conservative changes. The compelling arguments against this interpretation were clearly stated by Fisher in 1930 (ref. 4). He demonstrated that selection is very unlikely to favour extreme changes.

Arthur James Cain (1921-99)

Arthur Cain -- naturalist and doughty Darwinian, who did seminal work in ecological genetics and was a standard bearer for the view that most evolutionary changes are not neutral in terms of natural selection.

Arthur James Cain (1921–99): Obituary

Arthur Cain -- naturalist and doughty Darwinian, who did seminal work in ecological genetics and was a standard bearer for the view that most evolutionary changes are not neutral in terms of natural selection.

Obituary: Arthur James Cain (1921–99)

Arthur Cain -- naturalist and doughty Darwinian, who did seminal work in ecological genetics and was a standard bearer for the view that most evolutionary changes are not neutral in terms of natural selection.

An essayist worth his saltations

Eight Little Piggies: Reflections in Natural History.By Stephen Jay Gould. Norton/Jonathan Cape: 1993. Pp. 507.

The Proper Study

22.95, £18.99.

Algebra of Genetics

Comparative Genetics in Monkeys, Apes and Man.Edited By A. B. Chiarelli. (Proceedings of a symposium on Comparative Genetics in Primates and Human Heredity, held at Ernice, Sicily, July 1970.) Pp. x + 346. (Academic: New York and London, December 1971.) £5.50;

Maintenance of histocompatibility polymorphisms.

16.50.

Evidence for Apostatic Selection by Wild Passerines

Population GeneticsBy W. J. Ewens. (Methuens Monographs on Applied Probability and Statistics.) Pp. xii + 147. (Methuen: London, February 1969.) 30s.