In this image we see 16 Drosophila melanogaster fly embryos, photographed during their development under a confocal microscope. Fluorescent markers for different proteins have been injected into the embryo, so researchers can see exactly where they are expressed (produced). The labelled proteins here are involved in organising the embryo into different parts as it develops, so we can see that they are expressed in stripes along the body to help split it into segments. Some of these may then go on to form head, thorax and abdomen regions in the developing larva.
Images courtesy of Stephen Paddock and the Nikon Small World competition.