Animal sex chromosomes typically carry the upstream sex-determining gene that triggers testis or ovary development and, in some species, are regulated by global dosage compensation in response to functional decay of the Y chromosome. Despite the importance of these pathways, they exhibit striking differences across species, raising fundamental questions regarding the mechanisms underlying their evolutionary turnover. Recent studies of non-model organisms, including insects, reptiles and teleosts, have yielded a broad view of the diversity of sex chromosomes that challenges established theories. Moreover, continued studies in model organisms with recently developed technologies have characterized the dynamics of sex determination and dosage compensation in three-dimensional nuclear space and at single-cell resolution. Here, we synthesize recent insights into sex chromosomes from a variety of species to review their evolutionary dynamics with respect to the canonical model, as well as their diverse mechanisms of regulation.

动物性染色体通常携带触发睾丸或卵巢发育的上游性别决定基因，在某些物种中，响应 Y 染色体的功能衰变而受到全局剂量补偿的调节。尽管这些途径很重要，但它们在不同物种之间表现出显着差异，这引发了关于其进化转换机制的基本问题。最近对非模式生物（包括昆虫、爬行动物和硬骨动物）的研究对性染色体的多样性提出了广泛的认识，这挑战了既定的理论。此外，使用最近开发的技术对模式生物的持续研究已经表征了三维核空间和单细胞分辨率下性别决定和剂量补偿的动力学。在这里，我们综合了对各种物种性染色体的最新见解，以回顾它们相对于经典模型的进化动力学，以及它们的不同调节机制。