This book continues the stellar reputation of the original Atlas by providing updated, in-depth anatomical content and morphological views of organ systems. The book explores the developmental origins of the organ systems, following the original atlas as a continuation of the standard in the field for developmental biologists and researchers across biological and biomedical sciences studying mouse development. In this new edition, each chapter has been updated to include the latest research, along with while new chapters on the functional aspects of mouse and human heart development, the immune system, and the inner ear.