| Air Sacs (1 tracked article) |
| Animal Fins (11 tracked articles) |
| Animal Shells (9 tracked articles) |
| Arthropod Antennae (5 tracked articles) |
| Beak (4 tracked articles) |
| Egg Shell (4 tracked articles) |
| Electric Organ (4 tracked articles) |
| Fat Body (1 tracked article) |
| Feathers (25 tracked articles) |
| Forelimb (62 tracked articles) |
| Ganglia, Invertebrate (1 tracked article) |
| Gills (4 tracked articles) |
| Gizzard, Non-avian (1 tracked article) |
| Hemolymph (1 tracked article) |
| Hindlimb (18 tracked articles) |
| Hoof and Claw (5 tracked articles) |
| Horns (4 tracked articles) |
| Lateral Line System (1 tracked article) |
| Mammary Glands, Animal (4 tracked articles) |
| Mushroom Bodies (3 tracked articles) |
| Optic Lobe, Nonmammalian (1 tracked article) |
| Oviducts (3 tracked articles) |
| Photoreceptor Cells, Invertebrate (2 tracked articles) |
| Stomach, Ruminant (3 tracked articles) |
| Tail (20 tracked articles) |
| Vibrissae (4 tracked articles) |