The human brain is the most complex object in the known universe. But what about a fruit fly's? While only the size of a pinhead, it's still pretty motherf'ing complicated. Which is why a team of scientists at the Howard Hughes Medical Institute used an ingenious technique called "Brainbow" to make their job easier, revealing fine neural structures with unprecedented clarity.
Before Brainbow, scientists interested in tracing the structural connections between neurons could only color-code them one or two at a time using crude dyes. That meant slicing, staining, and combining many separate samples to build up a map of even tiny portions of a brain. Brainbow uses genetically engineered fluorescent proteins to make the neurons color-code themselves, right in the brain, in up to 100 different glowing colors. This makes it easier for scientists to clearly map the overall structure and tangled mass of connections, and also zero in on tiny individual areas of interest. Call it neuroscience by way of Massimo Vignelli.
Brainbow had already been demonstrated on lab mice, so why use it on lowly drosophila melanogaster instead of a bigger, "cooler" animal? As Technology Review explains, "these organisms have a very sophisticated set of existing genetic tools, [so] researchers can exert even greater control over when and where the fluorescent proteins are expressed." Which means better, more informative pictures, and better, more informative science. (The researchers' modified color-coding techniques for the fruit fly are called dBrainbow and Flybow.)
Take a gander at the inside of a fruit fly's skull in this slideshow. It may be a pinhead, but in many ways, it's still smarter and more sophisticated than any supercomputer we've ever built. With tools like Brainbow, scientists can learn more about them than ever before.