Chapter 8: Crocodilians and Birds

What are the parts of the feather?

-Shaft Parts (Calamus and Rachis)

-Vane

-Barb and Barbule

What are the 5 basic types of feathers

-Contour

-Semiplumes

-Down Feathers

-Bristles

-Fitoplumes

What kind of feather is this?

Contour

What kind of feather is this?

-Semiplume

What kind of feather is this?

-Down Feathers

What kind of feather is this?

-Bristles

What kind of feather is this?

-Filoplumes

Explain the feather type Contour

-Highly developed and forms outline of wing

-Flight feathers

Primaries = Located between wrist and tip of wing

Secondaries = Located between wrist and elbow

Rectrices = Go on tail feathers

Coverts = Overlap flight feathers

Explain the feather type of Semiplumes

-Loosely webbed

-Helps insulate body

-Helps with buoyancy in water birds

Explain the feather type of Down Feathers

-Small and Fluffy

-Beneath and between contour feathers

-Insulation

-Chicks usually have

Explain the feathers type of Bristles

-Modified, typically vaneless and consists only of a shaft

-Found near mouth, eyes, and nostrils

-Helps filter incoming air in nostrils

-Helps trap insects and acts as sensory function around mouth

Explains the feather type Filoplumes

-Specialized hair like feathers

-Between contour feathers

-Threadlike shaft and generally lack vanes

-Decorative and/or sensory (Peacocks)

What are Prenuptial Molts?

-Before breeding molting

-Migratory birds molt before migrating

What are Postnuptial Molts?

-After breeding and nesting

What are the 3 major types of horny sheaths on avian legs?

-Scutellate

-Booted

-Reticulate

Explain horny sheaths Scutellate and give example

-Overlaps on anterior surface of leg

-Finches and Sparrows

Explain horny sheath Booted and give example

-Smooth scales

-Thrushes

Explain horny sheath Reticulate and give an example

-Small irregular nonoverlapping scales

-Geese and Shorebirds

What type of vertebrae crocodilians have?

-Caudal Vertebrae

What type of vertebrae birds have?

-Cervical

-Thoracic

-Lumbar

-Sacral

-Caudal

Why do we see different shapes of beaks?

-Courting rituals

-Nest building

-Prey

-Diet

-Pruning

What are birds skeletons specialized for?

-Strength and Lightness (but have paper-thin bones)

What type of birds have a keeled sternum?

-Carinate Birds

-Penguins

What type of birds lack a keeled sternum?

Flightless Birds (Aka Ratites)

What type of birds have a furcular?

-Carinate Birds

Furcula = wish bone

What is Carpometacarpus?

-Found in hands of birds

-Fusion of carpal and metacarpal bone

What is Tibiotarsus?

-Fusion of Tibia and Tarsal

-Main bone in bird leg

What is Tarsometatarsus?

-Fusion of Metatarsals and tarsals

-Found in lower leg

What types of feet adaptations are there in birds?

-Webbed toes (Swimming)

-Perching

-Scratching

-Walking

-Grasping

-Wading

-Climbing

What are the two colors types of skeletal muscles and describe them

White: -Short bursts of intense activity

Red: -Smaller richer blood supply

-Hemoglobin and myoglobin

Which muscle in birds is proportionately the most massive of any tetrapod?

-Pectoralis Muscles

What do extrinsic and intrinsic integumentary muscles do in birds?

Instrinsic Muscle: -Controls the distal movements of the wing

Extrinsic Muscle: -Moves the eyes, wings, syrinx

Describe the lungs of crocodilians

-Consists of numerous large chambers

-Spongy Lungs

-Contains Alveoli for gas exchange

Describe the lungs of birds

-Small lungs (Unique duct system in)

-Contains Air sacs

Air Enters → External Nares → Nasal Canals → Exit through Internal Nares

What is the unique voice box is in birds?

-Syrinx

Describe the digestive system of Crocodiles

-Stomach is gizzard-like compartment

-Small intestine breaks down into 3 parts (Duodenum, Jeunum, Ilieum region)

-Gastric juice in stomach (Aids in digestion and neutralize any stomach acid)

What is the purpose of the Crop?

-Lower portion of esophagus

-Temporarily stores food and digestion before reaching the stomach

-In grain-eating birds/seed eating

What are the two regions in which the stomach is divided for grain and seed-eating birds?

Glandular Proventriculus: -Secretes gastric juice

Gizzard: -Helps with grinding function

Describe the Nervous system of Crocodilians

-Enlarged cerebral hemisphere partially

-Cerebellum

-Lack pineal organ

-Nerve packed bumps (Helps sense environment and prey)

Describe the Nervous system of Birds

-No vomeronasal organs

-Similar cerebral hemispheres to Crocodiles

-Large Cerebellum

-Large and well developed optic lobe

What is the best sense for birds and what do they use this sense for?

-Sight

-Forging, Avoiding/seeing branches, Mate selection, territory

What is a proposed evolutionary adaptation for female birds to have only one function ovary and oviduct?

-To lighten body for flight

Give example of sexual dimorphism in birds

-Color

-Tail size

-Bill curvature

-Brightly colored plumage for breeding season

-Typically visual or auditory

Give examples of different mating displays in birds?

-Aerial

-Postural

-Building nests

-Lekking

Describe mating display Lekking

-Males gather in an area

-Males display

-Females come around and pick the best male to mate with

What are the 3 different shapes of bird eggs?

-Elliptical

-Oval

-Pyriform

Describe egg shape Elliptical

-Curvature on both ends that are about the same size

What egg shape is this?

-Elliptical

Describe egg shape Oval

-Very round on both ends

-Wide in the middle

What egg shape is this?

Oval

Describe egg shape Pyriform

-Pear shaped

-One large end, one small end

What egg shape is this?

-Pyriform

What are the two structures that develop on birds to aid in hatching from eggs?

-Egg tooth

-Muscles on back of head (Helps crack and break egg open)

What is an Egg tooth and its function?

-A Caruncle

-Used to weaken shell cracks due to pressure from young and increased movement

What is the difference between precocial and altricial young and the amount or parental care for each?

Precocial: -Born ready to go

-Very little parental care

-Can walk, swim, move almost right away

Altricial: -Born naked

-Needs a lot of parental care

-Fragile

What are the different ways that Avian species show parental care?

-Incubate eggs (retrieve displaced eggs)

-Feed young