In their seminal 1983 paper, Gans and Northcutt proposed that evolution of the vertebrate ‘new head’ was made possible by the advent of the neural crest and cranial placodes. The neural crest is a stem cell population that arises adjacent to the forming CNS and contributes to important cell types, including components of the peripheral nervous system and craniofacial skeleton and elements of the cardiovascular system. In the past few years, the new head hypothesis has been challenged by the discovery in invertebrate chordates of cells with some, but not all, characteristics of vertebrate neural crest cells. Here, we discuss recent findings regarding how neural crest cells may have evolved during the course of deuterostome evolution. The results suggest that there was progressive addition of cell types to the repertoire of neural crest derivatives throughout vertebrate evolution. Novel genomic tools have enabled higher resolution insight into neural crest evolution, from both a cellular and a gene regulatory perspective. Together, these data provide clues regarding the ancestral neural crest state and how the neural crest continues to evolve to contribute to the success of vertebrates as efficient predators.

在 1983 年的开创性论文中，Gans 和 Northcutt 提出，神经嵴和颅底板的出现使脊椎动物“新头部”的进化成为可能。神经嵴是一个干细胞群，它产生于正在形成的中枢神经系统附近，并有助于形成重要的细胞类型，包括周围神经系统和颅面骨骼的成分以及心血管系统的成分。在过去的几年里，新的头部假说受到了无脊椎动物脊索动物中发现的具有脊椎动物神经嵴细胞的一些但不是全部特征的细胞的挑战。在这里，我们讨论了关于神经嵴细胞在后口动物进化过程中如何进化的最新发现。结果表明，在整个脊椎动物进化过程中，神经嵴衍生物的库中逐渐增加了细胞类型。新的基因组工具能够从细胞和基因调控的角度更高分辨率地洞察神经嵴的进化。总之，这些数据提供了有关祖先神经嵴状态以及神经嵴如何继续进化以促进脊椎动物成为高效捕食者的线索。