Animals are grouped into ~35 ‘phyla’ based upon the notion of distinct body plans 1 , 2 , 3 ,
4 . Morphological and molecular analyses have revealed that a stage in the middle of …

Communication in bilaterian nervous systems is mediated by electrical and secreted signals;
however, the evolutionary origin and relation of neurons to other secretory cell types has …

Ascidian larvae develop after an invariant pattern of embryonic cleavage. Fewer than 400
cells constitute the larval central nervous system (CNS), which forms without either extensive …

Animals are typically composed of hundreds of different cell types, yet mechanisms
underlying the emergence of new cell types remain unclear. Here we address the origin and …

Tissues similar to vertebrate cartilage have been described throughout the Metazoa. Often
the designation of tissues as cartilage within non-vertebrate lineages is based upon sparse …

The development of the endoderm is a multistage process. From the initial specification of the
endodermal domain in the embryo to the final regionalization of the gut, there are multiple …

We report the characterization of the ortholog of the Xenopus XlHbox8 ParaHox gene from
the sea urchin Strongylocentrotus purpuratus, SpLox. It is expressed during embryogenesis, …

Connective tissues are responsible for much of the variation in morphology that we see
today. Cartilage is a type of connective tissue that is often considered to be restricted to …

Cephalopods provide an unprecedented opportunity for comparative studies of the developmental
genetics of organ systems that are convergent with analogous vertebrate structures. …

Background The recent combination of genomics and single cell transcriptomics has allowed
to assess a variety of non-conventional model organisms in much more depth. Single cell …