Unborn vertebrates refer to animals that are still in their embryonic or fetal stages, and have not yet been born. There are several synonyms for the term unborn vertebrate, including developing embryos, fetuses, pre-birth animals, and gestating creatures. Unborn vertebrates can be found across various species, including fish, reptiles, birds, and mammals. These unborn creatures require specialized care and protection as they grow within the mother's body. Researchers and scientists often study the development of unborn vertebrates to better understand the origins and early stages of life. By examining the similarities and differences between various species of unborn vertebrates, we can gain a deeper appreciation for the diversity of life on our planet.