Using a bit of magnetic wizardry, a team of scientists has levitated common fruit flies. The insects were suspended in mid air with no strings or holders attached.
The experiment, outlined in the latest issue of the Journal of the Royal Society Interface, adds flies to the relatively short list of critters that have been levitated for the sake of science. Back in 1997, an international team of researchers floated a frog in mid air. The same group has also levitated plants, grasshoppers and fish.
In all cases, incredibly strong magnets were behind the Harry Potter-like magic. A primary aim of the studies is to simulate the zero gravity conditions experienced during space missions.
"The advantage, of course, of doing these experiments on the ground is it's a lot cheaper," lead author Richard Hill told Discovery News. "And we don’t have to worry about any effects of the high g-forces launching the flies into space on a rocket."
Hill, a senior research fellow in the University of Nottingham's School of Physics and Astronomy, and his team used a very powerful superconducting magnet to levitate common fruit flies, so named because they're often seen buzzing around rotting fruit.
The flies were subjected to what’s known as a diamagnetic force, created by the magnet. Diamagnetic materials, such as water, are pushed away by magnetic fields, so a really strong magnetic field can hold up flies, fish, frogs and so on, because these living things are mostly made up of water.
"If you have a magnet that is big enough, you could levitate a human," said Peter Main, a professor at the Institute of Physics who worked on the earlier studies.
The levitation occurs because living entities consist of millions and even billions of atoms, which contain electrons that move around a central nucleus. When they encounter a super strong magnet, as for the experiments, the electrons shift their orbits, giving the atoms their own magnetic field.
In those moments, the flies, frogs and other test subjects then consist of numerous tiny "magnets," which permit the bodies to float.
Hill and his team kept the flies up for a while, to see how they'd move.
"What we showed was that the flies in the magnet behaved in the same way that they behave in space," he said. "They walk more quickly."
"Why they do this, we really don't know yet," he added. "It may be because the flies just find moving around in weightlessness easier, or it could be that it's some kind of response to confusion about which way is up or down."
Levitated beings don't seem to suffer any ill effects.
In terms of the test frog, Hill said, "It went back to its fellow frogs looking perfectly happy." Fruit flies are smaller, more common, and are easier to deal with, however, so the success of this latest study suggests they may be used again in future to find out how life forms respond to an environment with a different gravitational field than Earth.
"We can simulate the gravity on the moon or on Mars, for example," Hill said.
Atsushi Higashitani, a professor in the Graduate School of Life Sciences at Tohoku University, told Discovery News that “nowadays, we know the effect of microgravity on organisms, including human astronauts, for several months” in duration.
Higashitani hopes the future studies will not only help to further answer some of the mysteries surrounding behavior in space, but will also reveal how living in space, or simulated space, will affect the offspring and grand-offspring of test animals.
Such information could be used to see if humans and other species could really thrive, procreate, behave normally, and live for extended periods in space or on other planets.