Avian evolution is the study of how birds have evolved over millions of years, from their ancestors to the diverse species we see today. This field of research focuses on understanding the genetic, morphological, and behavioral changes that have occurred in birds throughout their evolutionary history. Scientists study fossil records, comparative anatomy, molecular genetics, and other data sources to reconstruct the evolutionary relationships among different bird species and understand how various traits and adaptations have evolved. Avian evolution provides valuable insights into the origins of birds, their relationships with other animals, and the ecological roles they play in different ecosystems.