Our understanding of vertebrate origins is powerfully informed by comparative morphology,
embryology and genomics of chordates, hemichordates and echinoderms, which together …

The central nervous system (CNS) in different animals develops under the control of genes
that are often conserved both structurally and functionally. The question of whether such …

The chordate central nervous system has been hypothesized to originate from either a
dorsal centralized, or a ventral centralized, or a noncentralized nervous system of a …

The deuterostome phyla include Echinodermata, Hemichordata, and Chordata. Chordata is
composed of three subphyla, Vertebrata, Cephalochordata (Branchiostoma), and …

We have compared the dorsoventral development of hemichordates and chordates to
deduce the organization of their common ancestor, and hence to identify the evolutionary …

Systematics has developed rapidly during the past two decades. A multitude of new
methods and contributions from a diversity of biological fields including molecular genetics …

In 1983, a new theory, the New Head Hypothesis, was generated within the context of the
Tunicate Hypothesis of deuterostome evolution. The New Head Hypothesis comprised four …

Gene duplication and diversification can provide the raw material for the evolution of new
morphologies. In plants, the numbers of MADS-box genes have multiplied considerably …

This study investigates whether the recently described Cambrian fossil Haikouella (and the
very similar Yunnanozoon) throws light on the longstanding problem of the origin of …

The origin of the chordate central nervous system (CNS) is unknown. One theory is that a
CNS was present in the first bilaterian and that it gave rise to both the ventral cord of …