Early development of nematode embryos: differences and similarities

To determine whether embryogenesis of Caenorhabditis elegans is typical for nematodes in general, we started to analyse in comparison several aspects of development in various nematode species. The differences we observed can be subdivided into two classes, those visible in the intact embryo and those requiring experimental interference. Particularly obvious differences of both types were revealed between C. elegans (Rhabditidae) and Acrobeloides nanus (Cephalobidae). Not only does the spatial and temporal pattern of early events differ but also that of intercellular communication and cell specification. Our data suggest that some developmental variations are characteristic for certain nematode groups and therefore may be useful as phylogenetic markers. In contrast, we detected little evidence so far for environmental influence on early developmental processes.