What’s behind the predictably loopy gut
Between conception and birth, the human gut grows more than two meters long, looping and coiling within the tiny abdomen. Within a given species, the developing vertebrate gut always loops into the same formation — however, until now, it has not been clear why. Using a combination of experimental observations, biological and biophysical manipulations, theory, and computation, researchers at Harvard have shown that a “simple” balance of forces determines the form of the gut. The finding may shed light on how the gut has been able to evolve to accommodate changes in diet. The interdisciplinary research, published in the Aug. 4 issue of Nature, demonstrates that differences in growth rates between the gut tube and the neighboring mesenteric tissue force the tube to coil, regardless of the space constraints. “One might think that the gut tube coils because it is restricted by the size of the abdominal cavity. That’s actually not the case,” says...