Sperm development is approximately the same for all species and life forms. Scientists have therefore looked at how the sperm of the tiny fruit flies arise. Their find: The spermatozoa start as a kind of "bunch of flowers" of connected cells, which only come apart in the course of their development. In the head there is the nucleus with the genetic information, in the tail the ability to swim fast, and finally to arrive at the ovum in front of everyone else. At which end but the head should form, reveals the concentration of the molecule PIP2, which is marked red in the picture. If there is too little PIP2, the head will grow at the wrong end and the sperm will not work. This finding could help to understand infertility in humans as well.
Photo: Lacramioara Fabian and Julie Brill, The Hospital for Sick Children, Toronto, Canada© science.de