Abstract
To celebrate the tenth anniversary of BMC Biology, we asked our Editorial Board members to say what they thought were some important or interesting open questions in biology [1]. Contributions range from a paragraph or two, like the collection below, to slightly longer contributions, the first two of which are also published this month [2, 3]. We will publish these short contributions regularly during the year, to reflect the interests and preoccupations of our Editorial Board and perhaps stimulate answers from our readers.