Vertebrate development refers to the process by which animals with backbones, such as mammals, birds, reptiles, amphibians, and fish, grow and mature from a single fertilized egg. This process involves several stages, including cleavage, gastrulation, and organogenesis, where cells divide, differentiate, and form various tissues and organs. During development, vertebrates exhibit a series of changes, including the formation of the nervous system, musculoskeletal system, and circulatory system. These changes are guided by genetic instructions and environmental factors, ensuring that the organism develops properly and can function effectively in its environment.