In long germ-band insects such as Drosophila, the embryonic germ anlagen occupies the majority of the egg (A), whereas in the short germ-band Tribolium, the anlage is only a fraction of the egg (B). In long germ-band insects the entire AP body axis is specified by the end of the blastoderm stage. In short germ-band insects, only the anterior body is specified, and the rest of the posterior body forms through a process of posterior growth in the growth zone, which will eventually form the abdomen.