What similarities in developement led scientists to infer that vertabrate species share a common ancestor?

Scientists infer that vertebrate species share a common ancestor due to similarities in early developmental stages, such as the presence of pharyngeal slits, a notochord, and a dorsal nerve cord in embryos. These shared embryonic features suggest a common evolutionary origin, as they are observed across various vertebrate species despite differences in adult forms. Additionally, the patterns of organ development and skeletal structure further support the idea of a shared lineage among vertebrates. Such developmental similarities align with the principles of evolutionary Biology, indicating descent from a common ancestor.