Bird diversity, flight, communication - Week 23 Flashcards
What is Ornithology?
What is the size diversity of birds?
What habitats do they live in?
What is Ornithology?
- study of birds
What is the size diversity of birds?
-1.5g to 154kg
What habitats do they live in?
- every habitat in the world
What makes Aves unique?
Feathers!
What is the Arhaeoptery and why is this significant?
Late Jurassic 150-155 mya
Modification of outer skin, first feathers
Toothed beak, winged claws, long tail w vertebrae
Not long sustained flight, glider
Where did feathers evolve from?
Reptilian scales
Feathers general characteristics?
Made from beta keratin
lightweight, strong, waterproff
Number of feathers roughly constant within a species
Types of feathers?
Contour, down, semiplume, filoplume, bristle
What are contour feathers?
Cover all body but beak/ scaled legs Give bird smooth round shape Flight feathers = remiges Tail feathers = retries The first level of defence
Feather colouration pigments:
Melanins are?
Carotenoids are?
Melanins are?
- made by bird, black, grey, tan
Carotenoids are?
- in diet, red, yellow, orange
What are feathers functions?
Crypsis, avoid detection, sneak up on prey, escape preditor, behaviour type to match
Attraction,
Insulation, primary evolutionary force
flight
How are feathers cared for?
Preening (basic care), apply oils from uropygial gland, allopreening, bathing, moulting
What are some other avian features?
Forelimbs modified as wings, feathered tail, toothless beak
Endothermic
Flight
Flight:
Where has gliding evolved?
Where has activating flapping flight evolved?
- Evolved many times, usually in rainforests
- Only in birds, pterosaurs, insects
What are some adaptations for flight?
Feathers, light, strong, steamlined, flexible
Lightening of skeleton, loss of lower jaw
Beak is toothless, gizzard instead
Reproductions organs enlarge seasonally, oviparous
Strengthening of skeleton, fusion of bone
Muscles, pectoralis 35% of total body weight
Brain and sensory organ adaptations?
Eyes main sight, large eyes, proportional large brains, ample processing centres
How have wings adapted?
Elaborate joints, fused hand bone, powerful tendons, compact tiny muscles, airfoil shape
What are the flight mechanics and how do they interact?
Weight n lift, drag n propulsion/ thrust
Further to travel, air speeds up, pressure reduced, wing sucked upwards
More curved the airfoil, greater the lift
What are the different types of flight?
Gliding, weight used to overcome air resistance
Soaring types: maintains or increasing altitude without flapping
- Slope, dynamic and thermal
Flapping, adds thrust
Hovering, maintain a stationary position in the air
- true hovering, wind airfoil shape in up n down stroak
What are the different types of flight?
Gliding, weight used to overcome air resistance
Soaring types: maintains or increasing altitude without flapping
- Slope, dynamic and thermal
Flapping, adds thrust
Hovering, maintain a stationary position in the air
- true hovering, wind airfoil shape in up n down stroak
What are these wing shapes?
Elliptical?
High lift shape?
High speed?
Soaring?
Elliptical?
low aspect ratio, good manoeuvrability, fast take off, generate lots of drag, slotting displacement of drag
High lift shape?
Moderate aspect ratio, heavily cambered, carry a heavy load, minimise energy, terrestrial soaring species
High speed?
High aspect ratio, almost flat profile, aerial feeding, long migration
Soaring? Very high aspect ratio, narrow pointed shape reduces drag, sea birds, windswept environments
What are flight functions?
Feeding, courtship, migration, underwater flight
Underwater flight, increased flight, reduced buoyancy, smaller wings
Loss of flight, secondary loss, expensive, no need if reduced preditor risk
How is vocal communication produces?
Sounds produced by the respiratory system (no vocal cords) syrinx produce sound, almost all birds have this
Syrinx located where trachea branches into 2 primary branchi
Canaries sing with 1 side and breath with the other, continuous circular breathing
What are songs, daw chorus and cords?
Song: limited to the Passeriformes, often complex, primary under influence of sex hormone, important in reproduction
Daw chorus: Biggest sing session, sound stiller, sound travels further, less predators, less easy to see insects, birds lay eggs early
Calls: Given by most species, acoustically simple, not primarily sexual, maintenance activities
What are some functions of songs?
Chicks use calls inside eggs to provide temp, synchronise hatching and indicate hunger
Attract mates
Alarm calls
Calls to recruit others
Songs used to defend territories
Duetting and chorusing
