The orientation of many swimming algae, e.g. the species Chlamydomonas and Dunaliella, is biased by gravity and fluid shear. This is known as gyrotaxis. It causes the peculiar dispersion of suspensions of swimming algae in pipe flows, such as those in industrial photobioreactors. In a paper published today in the Journal of Fluid Mechanics, we present predictions for gyrotactic dispersion and compare them with experiments using fluorescently stained Dunaliella algae.