How animals establish and pattern the primary body axis is one of the most fundamental
problems in biology. Data from diverse deuterostomes (frog, fish, mouse, and amphioxus) …

The regulation of body axis specification in the common ancestor of bilaterians remains
controversial. BMP signaling appears to be an ancient program for patterning the secondary …

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

The startling capacity of the amphibian Spemann organizer to induce naïve cells to form a
Siamese twin embryo with a second set of body axes is one of the hallmarks of …

The origin of the bilaterian head is a fundamental question for the evolution of animal body
plans. The head of bilaterians develops at the anterior end of their primary body axis and is …

Bilaterality–the possession of two orthogonal body axes–is the name-giving trait of all
bilaterian animals. These body axes are established during early embryogenesis and serve …

In animals, body axis patterning is based on the concentration-dependent interpretation of
graded morphogen signals, which enables correct positioning of the anatomical structures …

Progress in resolving the phylogenetic relationships among animals and the expansion of
molecular developmental studies to a broader variety of organisms has provided important …

Patterning the neuroectoderm along the anterior–posterior (AP) axis is a critical event in the
early development of deuterostome embryos. However, the mechanisms that regulate the …

The nematode worm Caenorhabditis elegans has produced a wellspring of insights into
mechanisms that govern cellular symmetry breaking during animal development. Here we …