The complex chromatin-based genomic regulatory system controlling developmental gene expression in complex bilaterians predates the evolution of morphological complexity and may have been a prerequisite for the evolution of the first simple multicellular animals.
The cellular behaviours that underlie the internalization of the multilayered endoderm anlage in Xenopus laevis link the ancestral mode of vertebrate gastrulation to common, epithelial-based mechanisms of gastrulation in non-vertebrate animals.
A conserved alternative splicing program is specific to planarian stem cells and is controlled by the highly conserved splicing factors CELF and MBNL; therefore, this mode of regulating stem cells is likely ancestral to all animals.
The animal phylogeny of glutamate receptors indicates that vertebrate types do not account for all receptor classes originated during evolution, neither are they the pinnacle of a linear evolutive process.
High-resolution fluorescence imaging of the complete mouse brain enables many neurons to be efficiently visualized in their entirety, revealing all targets of neurons that project widely across the brain.