The birth of stars

The picture shows eggs being released from two pores on a starfish. The starfish have separate sexes, and release eggs and sperm into open water, where fertilization takes place. To maximize success, the release needs to be synchronized, but what exactly triggers it is unknown. The water temperature on this early march day was 5 degrees Celsius. Fertilized eggs will grow into larvae that swim around for a few weeks before they settle on the bottom and grow into starfish as we know them.