Read/Search this Article Temperate species of the Drosophila
melanogaster species group enter reproductive diapause for
overwintering in response to short daylength. During the
prediapause period, they accumulate triacylglycerols (TAGs) as
energy resources for winter. Under laboratory conditions, the
capacity for storing TAGs differs in different species, and
appears to be closely correlated with diapause and cold-
hardiness; cool-temperate species, such as those of the auraria
species complex which enter a deep diapause and are highly cold-
hardy accumulate a larger amount of TAGs than warm-temperate
species, such as D. rufa and D. lutescens which enter a weak
diapause and are less cold-hardy. On the other hand, a
subtropical species, D. takahashii, which has no diapause in
nature and is not cold-hardy, is unable to store as much TAGs as
the temperate species. These species were tested winter survival
and TAGs content under outdoor conditions in Sapporo (a cool-
temperate region) , northern Japan. In the strain