List and explain the different types of feathers in birds. (10 marks
- Contour feathers – cover the body, follow contours of the bird’s shape.
- Remexes which are classified into Remiges (wing feathers) & Rectrices (tail feathers) – specialized for flight.
- Down feathers – soft, without barbicels; insulate body (abundant in water birds).
- Filoplumes – hair-like, with shaft and few barbs; function uncertain.
- Powder down feathers – tips disintegrate to form waterproofing powder; grow continuously.
- Neonatal plumes – first feathers in chicks; simple structure; later replaced by contour feathers.
- Flightless feathers – lack barbicels, do not form vane; trap heat (ostrich, rhea).
What is the rhamphotheca, and what is it made of? (5 marks)
The rhamphotheca is the keratinous sheath covering the jaws of birds, forming the beak. It is made of keratin, the same protein found in feathers, scales, claws, and spurs
. Explain the tibio-tarsus and tarso-metatarsus in birds. (5 marks
- Tibio-tarsus – fusion of tibia and proximal tarsal bones.
- Tarso-metatarsus – fusion of distal tarsal bones with metatarsals.
These fusions strengthen the hind limbs, making them lighter and better adapted for walking, perching, and absorbing shock during landing
Describe the main locomotor muscles in birds. (8 marks)
- Pectoralis – depresses the wing (downstroke).
- Supracoracoideus – raises the wing (upstroke).
- Both originate on the keel of the sternum and insert on the humerus.
- Pectoralis inserts on the pectoral crest (ventral side), supracoracoideus on deltoid crest (upper side).
- Leg muscles – concentrated in the thigh around femur; strong tendons extend to toes.
- This arrangement keeps the centre of gravity low, aiding flight stability
describe feet adaptations in birds (10 marks)
1.Anisodactyl (perching birds, e.g. crows) – Three toes forward, one back; ideal for perching.
2.Zygodactyl (climbers, e.g. parrots, woodpeckers) – Two toes forward, two back; strong grip for climbing.
3.Syndactyl (e.g. trogons) – Third toe directed back with the first; aids in firm perching.
4.Totipalmate (swimmers, e.g. pelicans, cormorants) – All four toes forward and webbed; efficient for swimming.
5.Pamprodactyl (e.g. swifts) – All four toes reversible; adapted for hanging and clinging.
Comment on the senses of smell, taste, and hearing in birds. (5 marks)
- Smell & taste – poorly developed in most birds; exceptions: flightless birds, ducks, and two South American vultures.
- Hearing – very good; compensates for weak smell/taste.
- African vultures rely on sight; South American vultures rely on smell to find food
List and briefly explain comfort movements in birds. (5 marks
- Preening – oiling and repairing feathers.
- Scratching – removes irritations where bill can’t reach.
- Stretching – display behaviour showing colour patterns.
- Shaking – removes loose material or excess water.
- Bathing – water, dust, or sun-bathing for cleaning and parasite control.
- Anting – applying ants to plumage, unexplained function.
- Resting/Sleeping – safe places, linked to daily rhythm
. Differentiate between epitrepic and apotrepic behaviour. (5 marks)
- Apotrepic behaviour – aggressive or dominant postures in conflicts (offensive).
- Epitrepic behaviour – defensive or submissive postures; includes “freezing” behaviour
Discuss monogamy and polygamy in birds. (10 marks
- Monogamy – one partner per breeding season (90% of birds); seen in Hamerkop, Secretarybird, vultures. Both sexes care for young; males may defend territory. Seasonal monogamy common in migrants; some species (geese, vultures) form lifelong bonds.
- Polygamy – one individual mates with multiple partners.
o Polygyny – male with several females, e.g. masked weavers, bishops. Features: lek displays, sexual dimorphism, eclipse plumage, gregariousness, and nest building by males
*Polyandry- female mates with multiple partners per breeding season eg. African Jacana
Explain the four aerodynamic forces acting on birds in flight. (8 marks)
- Lift – upward force produced by aerofoil wing shape.
- Weight – downward pull of gravity opposing lift.
- Thrust – forward force generated by wing beats.
- Drag – air resistance opposing thrust
Describe how birds take off and land. (5 marks)
- Take-off –
o Small birds: jump into air and flap wings.
o Large birds: run along water/ground to build speed (geese, cranes, vultures).
o Perching birds: drop from perch and spread wings. - Landing – bird slows, flaps wings forward, spreads tail, lowers legs. The tibio-tarsal joint bends to absorb shock
Differentiate between the four types of bird wings with examples. (8 marks)
- Elliptical – short, broad; maneuverability in forests (sparrows, doves, woodpeckers).
- High-speed – long, tapering; fast flyers and migrants (swallows, swifts, plovers, terns).
- Gliding – long, narrow; oceanic soaring (albatross, frigate birds).
- High-lift – broad with slots; soaring predators (eagles, vultures, owls)
List and explain the main flying techniques used by birds. (6 marks
Gliding – Birds stretch wings horizontally and ride constant winds with minimal effort. Seen in large oceanic birds like albatrosses, gulls, and frigatebirds. (2)
Soaring – Birds use rising warm air currents (thermals) to gain height with little wing movement. Common in storks, pelicans, vultures, and large raptors. (2)
Flapping – Birds actively beat wings to generate both lift and thrust. The downstroke provides propulsion, while the upstroke resets the wing. Very energy-demanding. (2)
Describe migration in the Palaearctic, Neotropical, and Afrotropical regions. (8 marks
- Palaearctic – migration between northern temperate breeding areas and Africa/tropics (e.g. White Stork).
- Afrotropical – intra-African migrants (e.g. Yellow-billed Kite), altitudinal migrants (e.g. African Stonechat).
- Neotropical – similar patterns within the region, including long-distance migrations
Why are all birds considered oviparous? (5 marks)
All birds reproduce by laying eggs (oviparity). Fertilization is internal, but embryonic development occurs externally in a cleidoic egg with yolk and protective membranes. Incubation is external
. List the advantages of migration in birds. (8 marks
- Access to food
- Favourable climate
- higher breeding success
- reduced competition and overcrowding
- predator avoidance
- energy efficiency in survival
- escaping parasites and diseases
What is brood parasitism in birds? (5 marks)
Brood parasitism is when a bird lays its eggs in the nest of another species, leaving the host to incubate and rear its young. Examples include cuckoos and honeyguides
Name and explain the five types of epimeletic (care-giving) brooding behaviours. (5–8 marks
- Incubation – warming eggs.
- Brooding – warming and protecting chicks.
- Feeding young – regurgitation or direct feeding.
- Nest sanitation – removing waste/parasites.
- Protection/defense – guarding nest against predators
What is Etepimeletic behaviour? (3 marks)
etepimeletic behaviour is care-seeking behaviour by young birds, such as begging calls and gaping to solicit food and protection from parents
Advantages of being in a flock? (5 marks)
- Safety
- Easier to find a mate
- Less chances of getting lost during migration
- When cold, they come together and keep each other warm
- During feeding there’s a higher chance of getting food
discuss nest sanitation in birds for (8 marks)
Use of fresh materials – Raptors place fresh green leafy twigs in nests to cover faeces and keep the nest clean. (e.g. eagles, hawks).
Chick behaviour – Young raptors eject faeces and urine over the edge of the nest, preventing accumulation inside.
Faeces consumption – Some parents eat the droppings of chicks to maintain nest hygiene (e.g. mousebirds).
Faecal sac removal – Many passerines’ chicks produce mucous sacs around faeces, which parents carry away and discard far from the nest.
No cleaning behaviour – Some species do not remove waste, resulting in dirty nests (e.g. doves).
Functional waste accumulation – In doves, chick faeces help glue together the flimsy nest structure.
Protective role of waste – Accumulated faeces and food remains may deter predators due to their unpleasant smell.
tactics displayed by brood parasites (5 marks)
Egg mimicry – Parasite eggs closely resemble host eggs, preventing detection.
Rapid hatching – Shorter incubation gives parasite chicks an advantage over host chicks.
Quick egg-laying – Eggs are laid within seconds/minutes before the host returns.
Aggressive behaviour – Adults or chicks eject/trample host eggs and chicks.
Mimicry of chicks – Parasite chicks copy gape markings and plumage of host chicks to secure feeding.
