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Micro-evolution in a wine cellar population: An historical perspective

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The population of Drosophila melanogaster inside the wine cellar of Chateau Tahbilk of Victoria, Australia was found by McKenzie and Parsons (1974) to have undergone microevolution for greater alcohol tolerance when compared to the neighboring population outside the cellar. This triggered additional studies at Tahbilk, and at other wine cellars throughout the world. The contributions and interactions of researchers and the development of ideas on the ecology and genetics of this unique experimental system are traced. Although the ADH-F/ADH-S polymorphism was found to be maintained by selection in the Tahbilk populations, the selection is not significantly associated with alcohol tolerance. The environment inside the Tahbilk wine cellar is not as rich in ethanol as was originally anticipated, and selection that affects the alcohol dehydrogenase polymorphism may be more concerned with the relative efficiency with which ethanol is used as a nutrient by D. melanogaster. The synthesis and modification of lipids, particularly in membranes, appears to be important to alcohol tolerance. The studies of the Tahbilk population are at a crossroad. New experimental approaches promise to provide the keys to the selection that maintains the alcohol dehydrogenase polymorphism, and to factors that are important to alcohol tolerance and stress adaptation. From these research foundations at Tahbilk very significant contributions to our future understanding of the genetic processes of evolution can be made.
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... Alcohol tolerance is associated with the presence of a very abundant alcohol dehydrogenase (ADH) ( Van delden, 1982;Laurie et al., 1991). The Adh gene has an important role in adaptation to geographic and microgeographic variation of environment (Berry and Kreetmean, 1993;McKechnie and Geer, 1993). Natural populations of D. melunogaster exhibit large variations in their ethanol tolerance, often arranged according to latitudinal, clines (David et al., 1986). ...
... It was suggested that ADH was involved in the in vivo conversion of acetaldehyde into acetate in larvae, whereas an aldehyde dehydrogenase enzyme (ALDH) (EC 1.2.1.3 ) was responsible for this conversion in adults (Eisses et al., 1985;Geer et al., 1993;Lea1 andBarbancho, 1992, 1993). Other studies, however, indicated that both ADH and ALDH activities coexist in D. melunoguster larvae (Heinstra et al., 1989) and adults (Barbancho, 1992). ...
... In the present study, we used four toxic products involved in alcohol metabolism. Ethanol, which is often abundant in larval resources (Gibson et al., 1981;McKechnie and Morgan, 1982), is transformed into acetaldehyde by ADH while acetaldehyde is transformed by ALDH into acetate (Eisses et al., 1985;Geer et al., 1993;Lea1 andBarbancho, 1992, 1993). Isopropanol, which is only present at very low amounts in fermenting resources, is also used by ADH and transformed into acetone, which is presumably a metabolic dead end (Van Herrewege and David, 1980;David et al., 1981;Heinstra et al., 1987;Gonzalez-Duarte and Atrian, 1986). ...
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Evolution has led to a variety of adaptive processes which enable organisms to cope with an environment that changes. Internal homeostasis needs to be maintained for metabolic processes to continue and for DNA to replicate. Such adaptations occur at all levels of organisation. At one extreme, mobility and behavioural adaptations allow the organism to experience only optimal patches of a heterogeneous environment. Other adaptations enable the organism to thrive over a broad range of environmental extremes by making physiological/biochemical adjustments, which preserve “constant the conditions of life in the internal environment” (Claude Bernard, quoted from Haldane, 1932).
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Besides its central position for any biological study, evolutionary biology is also known for its many debates, controversies and dilemmas. Possibly the most conspicuous controversy of the last 2 decades is the neutralist-selectionist controversy concerning the significance of biochemical polymorphism (Kimura 1983). Also, the widespread use of the word adaptation, because of its several but imprecise meanings, has been also the subject of ancient (Williams 1966) or recent criticisms (Gould and Vrba 1982; Krimbas 1984).