Building a multicellular organism, even a fruit fly, is kind of like assembling a complicated piece of Ikea furniture. As with furniture, you have to assemble it in the right order. “There are many moving parts, many cell types, many organs, and the sequence and timing of events really matter,” says Philippe Batut, assistant professor of genetics and development at Columbia University Vagelos College of Physicians and Surgeons. “Genes have to be turned on at the right time and the right place, or you’re not going to get anywhere.”…
