... stages of significantly less divergent gene expression corresponding to the phylotypic stage in each evolutionary group. They also observed that the most consistent expression at these stages was among key developmental genes, rather than among genes controlling more specialized non-developmental...

... in relation to recent models of evolution and development. Surprisingly, differences in vertebral number are foreshadowed by different somite counts at the tailbud stage, thought to be a highly conserved (phylotypic) stage. Somite number therefore violates the ‘developmental hourglass’ model. We argue...

... 1995 Schistocerca Drosophila seven-up prospero neuroblast phylotypic stage CNS A central goal in developmental biology is to understand how development has evolved to generate diversity among organisms. We are addressing this question by comparing early neurogenesis...