The primitive streak, a structure that emerges during mammalian and avian gastrulation, might be a byproduct rather than a landmark of the embryonic development process.
Evidence is mounting that epigenetic marks on DNA can influence future generations in a variety of ways. But how such phenomena might affect large-scale evolutionary processes is hotly debated.
Studying how neural crest cells journey through the embryo, this Caltech developmental biologist has revealed how they form major cell types, including peripheral neurons, bone, and smooth muscle.
The finding confirms that a cluster of cells that directs the fate of other cells in the developing embryo is evolutionarily conserved across the animal kingdom.