Reveals Great Laws.

Star (Christchurch), Volume LXVI, Issue 20653, 29 June 1935, Page 10

Reveals Great Laws.

Nature Notes.

By James Drummond, F.L.S.. F.Z.S. 'J'HE COMMON FRUIT-FLY, condemned in New Zealand as a pest, has helped to reveal laws that control variation and heredity, which profoundly influence life. Its grubs love rotten-ripe and fermenting fruit and almost any decaying vegetable matter. They do not reject growing fruit. Eating gluttonously and thriving prosperously, they need only three weeks to develop into perfect fruit-flies. One generation follows another quickly. With a few glass tubes and a few pieces of banana, many fruit-flies can be reared in a laboratory quickly and easily. This has led to the discovery that they produce many modifications or variations, occuring in the colour and shape of the eyes, the colour of the body, the size, shape and veins of the wings, and the shape of the legs. Four hundred of these modifications from the normal type have been noted amongst millions of pedigreed fruit-flies reared, watched and recorded in captivity. They have been studied for another and widely different reason. They are a good subject for investigating coloured bodies in minute cells of protoplasm, which is the essential essence of all living things, the physical basis of life. As # the coloured bodies carry factors that influence heredity, they are highly important in studying hereditary characters. All this has made intensive observations of the fruit-fly a great work.