Comparative anatomy of vertebrates examines the structural similarities and differences across different vertebrate groups, including fish, amphibians, reptiles, birds, and mammals.
Comparative Anatomy of Vertebrates :
| Characters | Fish/Pisces | Amphibian | Reptile | Aves | Mammals |
| Habitat | Aquatic | Aquatic & Terrestrial | Terrestrial/ Aquatic | Terrestrial | Terrestrial/ Aquatic |
| Body Temperature | Poikilotherm | Poikilotherm | Poikilotherm | Homeotherm | Homeotherm |
| Locomotory organ/ Limbs | Fins | Fore limb- 4 digit Hind limb- 5 digit or limbless | Pentadactyl limbs Limbless- Snake | Fore limb- wings Hind limb- 4 digit | Pentadactyl limbs Fore limb- wings (Bat) |
| Endoskeleton | Cartilaginous/ Bony | Bony | Bony | Pneumatic bone | Bony |
| Exoskeleton | Dermal scales | __ | Epidermal scales | Epidermal scale, claw, beak, feather | Hair, nail, horn, claw, hoof |
| Stomach | Simple or absent | Simple elongated with gastric gland | Single chambered long or rounded | Two chamber -Proventriculus Gizzard | Single chamber or 4 chamber in ruminants |
| Respiration | Gills/ ARO | Gill/ Skin/ Lung | Lung | Lung | Lung |
| Heart | 2 chambered | 3 chambered | 3 and ½ chambered 4 chambered (crocodiles) | 4 chambered | 4 chambered |
| Excretion | Ammonia | Urea (adult) Ammonia (Larva/tailed species) | Uric acid | Uric acid | Urea |
| Kidney | Mesonephric | Mesonephric | Metanephric | Metanephric | Metanephric |
| Urinary Bladder | Absent | Present | Present or absent | Absent | Present |
| Skull | Monocondylic | Dicondylic | Monocondylic | Monocondylic | Dicondylic |
| Cranial nerve | 10 pairs | 10 pairs | 12 pairs | 12 pairs | 12 pairs |
| RBC | Nucleated | Nucleated | Nucleated | Nucleated | Enucleated |
| Fertilization | External | External Internal -(Urodeles) | Internal | Internal | Internal |
| Reproductive modes | Oviparous | Oviparous | Oviparous | Oviparous | Viviparous |
| Examples | Scoliodon sp. Labeo rohita Mystus sp. | Bufo sp. Ichthyophis sp. Salamandra sp. | Hemidactylus sp. Naja naja Crocodylus sp. | Columbia libia Bubo bubo Corvus sp. | Homo sapiens Panthera leo Rhinoceros sp. |