Explore: Vertebrates [mesh]

that are visible in extant jawed vertebrates (the Gnathostomes), which have seven arches, and primitive jawless vertebrates (the Agnatha), which have nine

in almost all vertebrates, but is absent in protochordates, in which there is a simple pineal homologue. The hagfish, archaic vertebrates, lack a pineal

Jawed vertebrates appeared by 445 Mya, tetrapods by 350 Mya, amniotes by 310 Mya and mammaliaforms by 200 Mya (approximately). Each vertebrate clade has

insects, the word trachea is used for a very different organ than in vertebrates. The respiratory system of insects consists of spiracles, tracheae, and

lens is known as accommodation (see also below). In many fully aquatic vertebrates, such as fish, other methods of accommodation are used, such as changing

conductions (in all jawed vertebrates) and centralized neural control by an highly functional brain, have allowed the vertebrates to achieve much larger

superficial fascia, is the lowermost layer of the integumentary system in vertebrates. The types of cells found in the layer are fibroblasts, adipose cells

The foot (pl.: feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion

cells, which are active in dim light and enable scotopic vision. Most vertebrates (including humans) have several classes of cones, each sensitive to a

non-vertebrate chordates such as tunicates a lineage of cells (melanocytes) has been identified, which are similar to neural crest cells in vertebrates.