Fruit Fly Organ Size

"How do body parts grow to the right size? Sometimes cells seem to follow an intrinsic genetic program. At other times, they appear to react to a cacophony of messages they receive from other cells and outside. A lot of the time, they seem to do a little of both. And in the case of cancer cells, the whole system has gone awry.⁣"
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⁣Illustration for Knowable Magazine's Special Report: Building Bodies.⁣