Ornithology Basic Characteristics-Form and Function

What are birds? Taxonomy –Kingdom Animalia Phylum Chordata –Class Aves

Characteristics Reptilelike but warmblooded Body covering of feathers (protein-keratin) Legs with scales Beek – adapted for food –Hummingbird long and needle-like for nectar –Cardinal “gross-beak” for cracking seeds Molting – change or replace feathers –winter vs. summer plumage

Digestive Gizzard- grinds food –Must eat small stones –Regurgatate for young Crop – stores food Rapid heat loss so high metabolism –Must maintain 41° C –Smaller birds must eat constantly

Respiration One-way flow of oxygen from from large air sacs to lungs constantly exposes lungs to oxygen-rich air –You and me have air in 2 directions ( in and out) Half the time we have to breathe oxygen-poor air How is their respiratory system advantageous to birds?

Digestion Wastes are removed from blood by kidneys and converted to uric acid (white)

Diversity 29 Orders of Birds –Here’s the main ones

Perching Birds Passerines- build nests –Largest order of birds most are songbirds Ex. Sparrows, crows, mockingbirds, cardinals

Birds of Prey Raptors- birds of prey Predators Hooked bills for tearing Large wingspans for gliding and observing Sharp talons for grasping Ex. Hawks, owls, eagles, falcons

Pelicans Aquatic ecosystems 4 webed toes Long bills for eating whole fish ex. Cormorants, ducks, geese

Cavity-Nesting Usually multicolored Live in holes, mounds or underground tunnels Ex. Woodpeckers, swallows, purple martins

Herons and Relatives Long featherless legs for wading Spoonlike bills for eating whole fish Ex. Storkes, blue heron, cranes

Flightless birds Run or swim Ex. Ostriches, emus, penguin

Characteristics (cont.) Adaptations associated with flight: –Skeleton Hollow bones –Musculature –Physiology –Reproductive system –CNS –etc…

Interesting biogeograpy Each faunal region has its characteristic birds – endemics

Biogeography (cont.) RegionsEndemic (non-passerines)Representative Family Radiation Holarctic Incl. Nearctic and Palearctic Loons, (Gaviidae) Auks (Alcidae) Accentors (Prunellidae) NW warblers (Parulidae) OW warblers (Sylviidae) NeotropicalRheas (Rheidae) Sunbittern (Eurypygidae) Motmots (Momotidae) Hummingbirds (Trochilidae) Tyrant-flycatchers (Tyrannidae) EthiopianOstrich (Struthionidae) Turacos (Musophagidae) Woodhoopoes (Phoeniculidae) Larks (Alaudidae) Sunbirds (Nectariniidae) OrientalNoneLeafbirds (Irenidae) Pheasants (Phasianidae) Flowerpeckers (Dicaeidae) AustralasianEmus (Dromiceidae) Kiwis (Apterygidae) Monarch-flycatchers (Monarchidae) Birds-of-paradise (Paradisaeidae)

Form and Function

Feathers Made of special protein - Keratin Function –Flight –Heat Conservation Reduced convective and evaporative heat loss Increased insulation

Feather Development Development triggered by an interaction b/w epidermis and dermal mesenchyme Formation of dermal papilla (placode) Mitotic divisions in a collar zone of the stratum germinativum near the base of the papilla form a crown of barbs Covered by a horny sheath of epidermis Lizard scales Scaleless hen Bird scales

Morphology of a Feather

Morphology of a feather (cont)

Major Types: –Contour Insul., Flight Vanes symmetrical Vanes asymmetrical –Semiplumes and Rachis > barbs –Down Rachis < barbs Insul. Adult down Natal down (lost) Powder down –Grooming –waterproofing –Bristles Little or no vane –Filoplume Monitor pennaceous feathors Attached to sensory corpuscles Plumulaceous Pennaceous

Contour feathers -flight Wings

Contour feathers Tail

Semiplume ostrich

Down natal adult powder

Bristles Whip-poor-will

Cross-section of feather follicle 1.Barb ridges of epithelial 2.Surrounding dermal core of connective tissue 3.Space of the follicle 4.Epithelial tissue of follicle 5.Associated musculature

Melanins

Carotenoids

Porphyrins

Structural colors