It is widely held that the bilaterian tubular gut with mouth and anus evolved from a simple gut
with one major gastric opening. However, there is no consensus on how this happened. Did …

caudal (cad/Cdx) genes are essential for the formation of posterior structures in Drosophila,
Caenorhabditis elegans, and vertebrates. In contrast to Drosophila, the majority of …

The Crustacea present a variety of body plans not encountered in any other class or phylum
of the Metazoa. Here we review our current knowledge on the complement and expression …

One of the earliest steps of embryonic development is the establishment of polarity along the
anteroposterior axis. Extensive studies of Drosophila embryonic development have …

The endoparasitic crustacean Sacculina carcini (Cirripedia: Rhizocephala) has a much
simpler morphology than conventional filter-feeding barnacles, reflecting its parasitic …

Members of the infraclass Cirripedia, commonly called barnacles, are unique among the
subphylum Crustacea in that they exhibit a biphasic life cycle with a planktonic larval stage …

Abstract Background The ParaHox gene cluster is the evolutionary sister to the Hox cluster.
Whilst the role of the Hox cluster in patterning the anterior-posterior axis of bilaterian animals …

The Crustacea is a highly diverse group. This diversity is seen in the various adult
morphologies consisting of different overall shapes, tagmatization, limb types, and segment …

The evolution of arthropod segmentation has been studied by comparing expression
patterns of pair-rule and segment polarity genes in various species. In Drosophila, the …

The evolution of arthropod body plans remains an irksome issue for the field of arthropod
systematics. For example, Gould believed it was illusory to use patterns of tagmosis as a …