Despite this, yunnanozoans’ classification has been controversial among researchers ... in Science concludes that yunnanozoans may be among the earliest vertebrates. Vertebrates are thought to have ...

Animals are divided into two main groups. Animals that have a backbone are called vertebrates. Animals that don't have a backbone are called invertebrates. Vertebrates and invertebrates are ...

Membrane-bound immunoglobulins are expressed earlier in ontogeny than the secreted forms; both forms are found in jawed vertebrate lymphocytes. Notwithstanding the role of MHC class I and II ...

He doesn't even have a head. If Blob had been born with a spine, or backbone, he would have been a vertebrate. If we give Blob some legs and a head then he can start to move about. There are lots ...