Arthropod embryology: Cleavage and germ band development

Abstract

The overwhelming diversity of arthropod morphology and lifestyles finds it correspondence in a comparatively impressive variety of developmental trajectories. These ontogenetic differences concern all embryonic stages, steps, and levels from gene expression, cleavage and gastrulation, germ band formation and growth, to segmentation and morphogenesis (Weygoldt 1960a, 1963; Anderson 1973; Scholtz 1997; Akam 2000; Hughes and Kaufman 2002a). Likewise, postembryonic development reveals all sorts of growth patterns, direct and indirect development and within the latter a great variety of larval types with a wide spectrum of lifestyles comparable to those of the adult forms (see Chap. 5). However, it has to be stressed that variation in development is not necessarily directly correlated or even causally linked to adult diversity. Similar adult body organization and shapes can result from very different ontogenies, whereas similar ontogenies can result in highly diverse adults (Scholtz 2005).