| Salient Feature | Chordates | Non-Chordates |
| Symmetry | Bilateral | Radial, bi-radial, bilateral, no symmetry |
| Metamerism | True metamerism | True or Pseudo-metamerism, or absent |
| Post anal tail | Usually present | Usually absent |
| Organisation | Organ system level | Protoplasmic level to Organ system level |
| Germ layers | 3, triploblastic | 2, 3, or lacking |
| Coelom | True coelomate | Acoelomate, Pseudocoelomate, true coelomate |
| Limb Derivation | Limbs derived from several segments | From same segment |
| Notochord | Present at some stage, or replaced by vertebrae rings | Lacking notochord or backbone |
| Gut position | Ventral to Nerve cord | Dorsal to nerve cord |
| Pharyngeal gill slits | Present at some stage of life | Absent |
| Anus | Differentiated, opens before last segment | Opens on last segment, or absent |
| Blood vascular system | Closed | Open, closed or absent |
| Heart | Ventrally placed | Dorsal, lateral or absent |
| Dorsal blood vessel | Blood flows posteriorly | Blood flows anteriorly |
| Hepatic Portal System | Present | Absent |
| Haemoglobin | In RBCs | In plasma or absent |
| Respiration | Through gills or lungs | Body surface, gills or trachea |
| Nervous System | Hollow | Solid |
| Brain | Dorsal to pharynx in the head | Above pharynx or absent |
| Nerve Cord | Single, dorsal, without ganglia | Double, ventral, usually bearing ganglia |
| Reproduction | Sexual reproduction is pre-dominant | Asexual reproduction is predominant |
| Body temperature | Cold or warm blooded | Cold blooded |