Beak modifications in birds
- 2. Objectives • Types of beak modifications in birds • Examples of birds with beak modification
- 3. Introduction • Birds- absence of teeth • Modified jaw bones – beak • Covered with sheath- Rhamphotheca • Beak = Fore Limb + Teeth • Variations - depending on food type and functions
- 4. 1. Seed eating beak • Strong, stout, short, conical • Broad at base & pointed at tip • Crushes large hard shelled seeds & fruits • Gram eating birds Small conical beak
- 6. 2. Cutting and biting type • Strong, sharp with cutting edges • Long and slender Crow
- 7. 3. Fruit eating beak • Break hard fruit nuts • Use for gnawing hard nuts & seeds, tearing fruits • Parrot- sharp, powerful, hooked, extremely strong
- 8. • Hornbill – large, enormous, heavy, cumbersome • Light in weight, interior is cellular • Acts as resonator to produce loud cry
- 9. 4. Insectivorous beak • Catch insect when they are flying • Small, wide , delicate • Examples: swallows ,swifts , robin
- 10. • Fly catcher: short, strong ,notched mandible at tip • bristles at base swifts Robin
- 11. • Hoopoe : long, slender slightly curved • For turning leaves & probing soil for insects grubs and pupae.
- 12. Type Use Example Shape Seed Eating Crushes hard seed Sparrow, fiches, cardinals Strong, Conical, base broad, pointed tip Cutting & Biting Cutting and biting crow Strong, long, slender Sharp edge Fruit Eating Breaking hard fruit Parrot, hornbill Sharp, Hooked, strong Insectivorous Catching flying insect Fly catcher, swallows , swift, hoopoe Small, wide, delicate
- 13. 5. Wood chiseling beak • Long, straight , stout, chisel like • Drilling wood for insect or nest building • Thickened, shock absorbing skull bone • Strong neck muscle • Ex: wood pecker
- 14. 6. Tearing & Piercing • Carnivorous birds • Short, pointed, sharp, edged, powerful, hooked • For tearing flesh • Well developed mandibular muscle • Example: Eagle, Owls, Kites, Hawks, Vulture
- 15. Owl Vulture Hawk Eagle Kites
- 17. 7. Fish catching beak • Long , powerful, sharply pointed • Capture fish , frogs, toads, aquatic animals
- 18. • Cormorant: long , narrow with curved edges sharp backwardly directed teeth • Indian Darter or snake bird: saw like teeth like fine needle
- 19. 8. Mud probing beak • Extremely long , slender • Long probes for searching down into mud Stilt
- 21. Type Use Example Shape Wood Chiseling Drilling into wood Wood pecker Long , straight, chisel like Tearing & Piercing Carnivorous birds Eagle, Hawk, Owl, Vulture, Kites Short, hooked , sharp Fish catching Capture fish frog, toads etc Heron, Kingfisher, Darter, Cormorant Sharply pointed , saw like Mud Probing Catching flying insect Lapwing, Sand piper, Stilt, Snipes Long , slender
- 22. 9. Water & mud straining • Edges of jaws- modified into Horney serrations or transverse lamellae • Acts as sieves or strainer • Example: flamingo – curved , downward & with transverse lamellae
- 23. Broad And Flat beak Duck transverse lamellae
- 24. 10. Spatulate • Flattened beak • Terminate in broad spoon • Dabbling in water & mud for insects, fish, worm etc. • Example: spoon bill
- 25. 11. Pouched • Attached to lower mandible • Acts as fishing net • Pouch like extensile skin • Example: pelican
- 26. 12. Flower Probing • Feeds on nectar of flower • Long , pointed • beak are bent a/c to flower shape • Can dive down to corolla of flower • Example: Humming Bird
- 27. Type Use Example Shape Water & mud straining Straining food from mud &water Duck, Geese, Flamingo Broad ,flat, transverse lamellae Spatulate Dabbling into water & mud Spoon bill Flat, spoon shape Pouched Acts as fishing net Pelican Pouch like extension Flower Probing Nectar of flower Humming bird Long ,pointed