Development, Regeneration, and Evolution of Feathers

The document reviewed the progress in understanding the development, regeneration, and evolution of feathers over the past three decades. It discussed the development of feather buds in chicken embryos, the regenerative cycling of feather follicle stem cells, and the formation of barb branching and pigmentation patterns. The interplay of hormones and feather growth was also examined, along with the genetic identification of several feather variants. The discovery of feathered dinosaurs redefined the relationship between feathers and birds, highlighting feathers' significance beyond avian biology. Additionally, feathers served as a model for morphogenesis studies and inspired biomimetic research due to their complex structure and functions in endothermy, communication, and flight.