Mathematics explains how giant ’whirlpools’ form in developing egg cells

The swirling currents occur when the rodlike structures that extend inward from the cells' membranes bend in tandem, like stalks of wheat caught in a strong breeze, according to a study from the University of Cambridge and the Flatiron Institute. The mechanism of the swirling instability is disarmingly simple, and the agreement between our calculations and experimental observations supports the idea that this is indeed the process at work in fruit fly egg cells Raymond Goldstein Egg cells are among the largest cells in the animal kingdom. Unpropelled, a protein could take hours or even days to drift from one side of a forming egg cell to the other. Luckily, nature has developed a faster way: scientists have spotted cell-spanning whirlpools in the immature egg cells of animals such as mice, zebrafish and fruit flies. These vortices make cross-cell commutes take just a fraction of the time. But scientists didn't know how these crucial flows formed. Using mathematical modeling, researchers say they now have an answer.