News Feature: A matter of timing
- Helen Fields, Science Writer
Lab animals’ circadian clocks do not always match the schedules of their wild cousins. Researchers are heading out into the field to understand why.
The humble fruit fly, that mainstay of the research laboratory, has a daily routine that runs like clockwork. “They wake up in the morning and they’re bright and bushy-tailed; they cruise around and they’re active. Then they have a siesta during the day, especially as it gets warmer. Then they’re out in the evening,” says Charalambos Kyriacou, a behavioral geneticist at the University of Leicester in the United Kingdom.
A pectoral sandpiper flies off after being fitted with a radio-transmitter, which researchers used to study its unusual circadian rhythm cycle. Image courtesy of Wolfgang Forstmeier, copyright Max Planck Institute for Ornithology.
Researchers found that the male pectoral sandpipers who sleep the least are the ones who father the most young, suggesting that the circadian rhythms may have emerged from a sexual selection pressure for these social behaviors. Image courtesy of Wolfgang Forstmeier, copyright Max Planck Institute for Ornithology.
Predictable and dependable, the circadian rhythms of Drosophila melanogaster have yielded a steady stream of insights. About 30 years ago, researchers discovered a gene that influenced the length of the flies’ circadian clocks: when it was mutated, flies were inclined to a longer or shorter day or no daily rhythm at all. Scientists have used these and other mutations to identify the proteins that underlie the circadian clock, to watch how their ebb and flow regulates events within our cells. From flies, it was a natural progression to understanding the functions of these proteins in humans.
However, since 2007, Kyriacou has made some startling discoveries that have sparked an ongoing debate in the world of insect chronobiology. Flies in their natural environment, he discovered, do not stick to …
