Study Sheet Exam 1 Questions Flashcards
What are some of the unique characteristics of birds?
Feathers
Beak/Bill (toothless)
Syrinx
What are some characteristics of birds that are not exclusive?
2-legged, bipedal vertebrate
Gizzards
Wings
Flight
Lay eggs
Endothermic
What traits do birds have that evolved for flight?
• Lightweight, (mostly) hollow bones
• Fusion in hand bones, head,pelvis, feet (lightening and strengthing skeleton)
• Furcula (Wishbone)
• Uncinate Processes
• Carpometacarpus
• Tibiotarus
• Tarsometatarsus
•Keeled sternum in birds that can fly (muscle attachment)
Summarize the importance of the Furcula
The furcula, or wishbone, compresses and rebounds like a powerful spring in rhythm to the beat of the wings. The wing itself is a highly modified forelimb that, with a few remarkable exceptions, is nearly incapable of functions other than flight.
Summarize the importance of the Uncinate Process
Horizontal, backward-curved projections—called uncinate processes—on the ribs overlap other ribs and so strengthen the walls of the body.
Summarize the importance of the Carpometacarpus
fused hand bones, supports and maneuvers the large and powerful primary flight feathers.
Summarize the importance of the Tibiotarsus
Summarize the importance of the Tarsometatarsus
Explain Adaptive Radiation and give an example of traits that show this
A phenomenon where great diversity develops due to the evolution of various species adapting to different ecologies and behaviors
Examples:
Beak sizes and shapes
Leg length
Wing shape
Summarize the importance of the Nasofrontal Hinge
Summarize the importance of the Trabeculae
Summarize the importance of the Rhamphotheca
Summarize the importance of the Cranial kinesis
What are some areas of greatest diversity in birds? Give some examples for each.
What is natural selection?
is the differential survival of individual organisms with advantageous traits.
(If the traits are heritable, then survivial will result in adaptive evolutionary change among generations.
Well adapted individuals live longer and produce more offspring.)
What is convergent evolution? Give an example.
the independent evolution of similar adaptations in unrelated organisms
Penguins and Auks ….
What is biogeography?
is the study of the geographical distributions of plants and animals. For more than a century, biogeographers have divided Earth into six major faunal regions corresponding roughly to the major continental areas.
What are the six major faunal regions?
Nearctic, Neotropical, Palearctic, Afrotropical, Indomalayan, Australasian
What are endemic species? Give an example.
Each faunal region has its characteristic birds: so-called endemic taxa or species, which are found nowhere else, and other birds that represent major adaptive radiations of more widespread taxa.
What are avifaunas?
regional assemblages of bird species—are mixtures of species of varied ages and origins
List out some of the shared characteristics between birds and reptiles.
• Scales
• Lay eggs
• Skull of both articulate with the 1st neck vertebrae by means of a single ball and socket device- the Occipital Condyle
• Simple middle ear with/ one ear bone - the Stapes
•Ankle is located in the middle of the tarsal bones (foot)
What are archosaurs? What are their defining traits?
are a specific group of reptiles that include alligators and crocodiles, dinosaurs, and pterosaurs
• Distinctive hole in side of skull, in front of eye socket, called antorbital fenestra
• Advanced parental care behavior
Which reptile did birds originate from?
Archaeopteryx lithographica
What are vanes? Why are they characteristic in Archeopteryx?
the planar surfaces of feathers, on either side of the feather shaft
Archeopteryx’s primary (flight) feathers had asymmetrical vanes.
Most modern birds that fly have asymmetrical vanes, especially strong fliers
What is a phylogenetic tree?
is a diagram that depicts evolutionary relationships (a phylogeny) among organisms
• Branches represent historic species evolving through time
•Nodes are points where branches split off, indicating a speciation event producing new lineages
• Clades represent all descendents (living or extinct) with a common ancestor.
What do clades represent?
Represent all dependents (living or extinct) w/ a common ancestor
Which of these are clades? Which are not? Why?
Green and blue are clades because…
Red and orange are not clades because…
What are homologs? Give an example.
Similarities inherited from a common ancestor
Examples:
Wings of all birds are homologs
What is the pygostyle?
a special bone created by a fusion of the vertebrae at the tip of the tail (important for flight)
What are therapods?
The phylogenetic sister group to the sauropods are the bipedal, meat-eating dinosaurs called theropods, which include the famous Allosaurus, Tyrannosaurus rex, Oviraptor, and Velociraptor. Birds are living theropod dinosaurs that are most closely related to the dromaeosaurs like Deinonychus and Velociraptor and to Troodon (see Figure 2–4).
What visual evidence do we have of feathers in therapods?
Archaeopteryx lithographica - 1877: Feathered reptile found fossilized in ancient coastal lagoon in Germany
What are the shared characteristics of birds and Archaeopteryx?
the earliest known fossil bird
1877: Feathered reptile found fossilized in ancient coastal lagoon in Germany
Crow-sized, bipedal reptile with tiny reptilian teeth and bony tail, but also had feathers on wings and tail with a backwards pointing toe called a Hallux.
Archeopteryx’s primary (flight) feathers had asymmetrical vanes.
Vanes are the planar surfaces of feathers, on either side of the feather shaft.
Most modern birds that fly have asymmetrical vanes, especially strong fliers
Did feathers originate with flight?
No….
What are the two basic theories of flight?
Arboreal (Gliding)
Cursorial (Running)
What is systematics? How is this done?
The investigation of evolutionary relationships among organisms.
This is done by examining:
• Fossils
•Preserved Specimens
•Behavior
•Genetic DNA
What does taxonomic classification do?
It provides the framework for understanding the evolution of behavior, ecology and morphology
What is taxonomy?
The science of naming and classifying organism according to standardized rules
What is a taxon?
Any group of animals that is recognized in a classification