d. melanogaster

Flying colors

Among bug-swatting produce managers, Drosophila melanogaster is more generally known as the common fruit fly, a tiny insect widely condemned as a pest. Among scientists, on the other hand, D. melanogaster’s is a valued and quite uncommon collaborator.

The tiny fly, like the specimen captured above by Thomas Deerinck using a scanning electron microscope, is a model organism, widely used by researchers investigating everything from the fundamentals of biological development to the nature of immortality.

It has been a subject of scientific utility longer than any other model (i.e. mice, rats, monkeys, etc). The first flies were studied more than a century ago. They have been used in thousands of studies. They remain a go-to bug.

There are many reasons why. One, the fly is small (2.5 millimeters long), so they take up very little lab space. They require a simple, cheap diet: rotten fruit. They reproduce prolifically: Females lay about 400 eggs each. And they don’t live very long. The entire lifecycle of a fly is about two weeks, which makes it possible for researchers to set up projects that monitor and measure changes occurring over multiple fly generations in just a matter of months.

The fly has other admirable attributes. It boasts large chromosomes with barcode patterns of light and dark bands that help researchers accurately map its genes. Indeed, D. melanogaster has been an invaluable tool in modern genetics. It has about the same number of gene families as humans (albeit half the number of genes). The relationship between fly and human genes is so close, in fact, that sequences of newly discovered human genes are often matched against their fly counterparts, providing clues to the function of the mysterious new human gene.