HighlightsThe amylolytic system of the digestive fluid of sea hare (Aplysia kurodai) was studied.Two α-amylases and two α-glucosidases were purified from the digestive fluid.Sea hare efficiently digests sea lettuce to glucose by a combination of these enzymes.Starch in sea lettuce is a predominant glucose source for sea hare.

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The hexane rinse from whole bodies of 5000 unmated females of the European grain moth Nemapogon granellus (Lepidoptera : Tineidae) was purified on a short Si02 column and an AgNO3 impregnated Si02 column, while the pheromone activity was monitored by a conventional behavioral bioassay.The analysis of the active principle(s) and its dimethyldisulfide (DMDS) derivative(s) by GLC and GC-MS indicated that the structure corresponded to that of 3, 13-octadecadienyl acetate.Only the 3Z, 1 3Z-isomer among the four candidates synthesized gave GLC and GC-MS results identical with those of the purified pheromone, and it was most active among the isomers. These results indicated that the female sex pheromone of the European grain moth was identical to (3Z, 13Z)-3, 13-octadecadienyl acetate.

Much effort has been made to search for signatures of past natural selection in DNA sequences. However, currently acting selection is rarely detected in natural populations because of its rarity, low detection power of available methods, or both. Here, we develop a new test to detect viability selection over a single generation. In this test, one specific type of chromosomes is chosen as a reference, while all other chromosomes are designated as "focal". The test compares measures of variation between two groups of "focal" chromosomes: those found in reference/focal heterozygous individuals and those found in focal/focal homozygous individuals. In the absence of selection, we do not expect differences between these two groups as long as mating is random. On the other hand, currently acting selection can cause differences in some measures of variation. We applied this test to typing data for In(2L)t inversion polymorphism in a Drosophila melanogaster population, using "standard" (non-inverted) chromosomes as the focal class. Although the frequencies of In(2L)t and standard chromosomes did not deviate from the Hardy-Weinberg equilibrium, we found differences in allele frequency and the number of haplotypes between the two groups of standard chromosomes. This new test, in conjunction with the Hardy-Weinberg test, may shed light on how often strong selection is operating in extant populations.