A whopping six Nobel prizes have been won for research on fruit flies. But what makes these humble little bugs so special?
Drosophila melanogaster, the common fruit fly, has been the superstar of genetic research for over a century. These alien-seeming creatures share more in common with humans than you might think. Around 75% of genes linked to human diseases are also present in drosophila, which means that these little flies can tell us a lot about ourselves.
Drosophila were first thrust into the limelight by Thomas Hunt Morgan, a geneticist who began working with flies in 1908. At the time, scientists were trying to figure out where the genes passed down from parents to children are hidden within cells. Researchers noticed that chromosomes pair up and split apart in a way that would make them ideal for carrying genes, but they had no proof for this theory.
To solve this conundrum, Morgan exploited the tiny size, speedy life cycle and cheap upkeep of his flies. He bred an entire city population of the creatures in glass jars, scouring them for signs of rare mutations. One day, Morgan spotted a fly with white eyes instead of the normal red. When he mated the white-eyed fly with red-eyed flies, all of the children had red eyes. Bizarrely, white eyes reappeared in the grandchildren — but only in some male flies. Because of this odd pattern and its connection to sex, Morgan realised that the gene for eye colour must be on the fly sex chromosome. In 1933, Morgan won the Nobel prize for demonstrating that genes are carried on chromosomes.
Morgan showed that flies are a simple creature that can be used to unpick complicated biology. Since Morgan’s experiments, scientists have enlisted the help of Drosophila to do Nobel prize-winning work on embryo development, the immune system, circadian rhythms, the sense of smell and much more. Today, flies help us to research life-threatening diseases such as Alzheimer disease and cancer, and to expand our understanding of the intricate inner workings of all living creatures.