The concept of heterochrony, which denotes a change in the relative timing of
developmental events and processes in evolution, has accompanied attempts to link …

Platynereis dumerilii, a marine polychaetous annelid with indirect development, can be
continuously bred in the laboratory. Here, we describe its spectacular reproduction and …

Indirect development with an intermediate larva exists in all major animal lineages, which
makes larvae central to most scenarios of animal evolution,,,,,,,,–. Yet how larvae evolved …

Abstract Background The polychaete annelid Platynereis dumerilii is an emerging model
organism for the study of molecular developmental processes, evolution, neurobiology and …

The trochophora concept and the literature on cleavage patterns and differentiation of
ectodermal structures in annelids (“polychaetes”) and molluscs are reviewed. The early …

The bilaterian animals are divided into three great branches: the Deuterostomia, Ecdysozoa,
and Lophotrochozoa. The evolution of developmental mechanisms is less studied in the …

In order to address the question of the conservation of posterior growth mechanisms in
bilaterians, we have studied the expression patterns of the orthologues of the genes caudal …

Annelids and arthropods, despite their distinct classification as Lophotrochozoa and
Ecdysozoa, present a morphologically similar, segmented body plan. To elucidate the …

Expression patterns for five Hox genes were examined by whole-mount in situ hybridization
in larvae of Chaetopterus, a polychaete annelid with a tagmatized axial body plan …

The debate on the origin of segmentation is a central question in the study of body plan
evolution in metazoans. Annelids are the most conspicuously metameric animals as most of …