Questions and Answers
What is the classification of the Class Aves?
What dinosaurs did birds evolve from?
Theropod Saurichian
Other than Theropod, what other dinosaurs did birds descend from?
Dromeosaurs, such as Velociraptor
Theropods are part of the 1.)___________ Reptiles that include 2.)__________ & other dinosaurs.
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In the evolution of birds, what would you say they were built for?
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In bird evolution, what type of evolution did birds undergo for flight?
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In bird evolution, what types of Exaptations did they undergo?
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Insects took flight before the ___________
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_______________ had already conquered the air
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What dinosaur was first discovered in rock that is 150 million years old, and was also the oldest known 'true' bird?
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This dinosaur had very reptile-like bone structure, but numerous adaptations for flight like the other flying tetrapods (bats, pterodactyls).
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What Reptilian features did the Archaeopteryx lithographica present?
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What older bird ancestor was dated 130 mybp and presented four-winged Microraptor?
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What did feathers evolve from?
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Did feathers evolve for flight?
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Most bird adaptations for ______ are completely unique to birds.
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What is the two major driving forces in bird evolution, and how does this aid in bird evolution?
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How does birds present weight-reducing adaptations?
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What was another evolution of birds' bones, other than hollow and thin, did they present?
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What are the characteristics of bird skulls?
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What are the characteristics of bird ribs?
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What are the characteristics of the birds' sternum?
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How do the feathers in birds aid in their life?
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What are the different types of feather structures present in birds?
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The beak of birds is made up of:
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In bird excretion, what do they not have?
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What is a side pouch off the cloaca?
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What do birds excrete? How does this help?
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In marine birds, what must they excrete, and how do they excrete this?
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What type of strict reproduction are birds?
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Birds are the only class of vertebrates without some form of ________ or __________...
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Study Notes
Classification of Birds
- Classified under Phylum Chordata, Subphylum Vertebrata, Diapsida clade, Archosauria clade.
- Class Aves includes two subclasses: Archaeornithes (ancient birds like Archaeopteryx lithographica) and Neornithes (modern birds).
Evolution of Birds
- Birds evolved from theropod dinosaurs, a subgroup of Saurichian reptiles.
- Additional ancestors include Dromeosaurs like Velociraptor.
- The evolution involved adaptations for flight known as exaptations.
Key Exaptations for Flight
- Bipedalism and hollow bones reduced body weight.
- Modification of forelegs into wings and the development of feathers.
Historical Context
- Insects achieved flight prior to pterosaurs, while pterodactyls also dominated the skies.
- The oldest known "true" bird, Archaeopteryx lithographica, dates back 150 million years.
Archaeopteryx Characteristics
- Combines reptilian features (scales, teeth, long tail) with adaptations for flight.
- Had a bone structure resembling reptiles but adapted forelimbs for flying.
Feather Evolution
- Feathers evolved from scales primarily for mating displays, defense, and temperature regulation, not initially for flight.
- Adaptations unique to birds support flight, such as feathers that provide lift, insulation, and streamlining.
Bones and Skeletal Adaptations
- Birds have hollow, thin, and fused bones to reduce weight while maintaining strength.
- Bird skulls are thin, porous and fused, minimizing mass.
Rib and Sternum Characteristics
- Ribs are long, thin, and overlap, while the sternum is large, light, and hollow.
Excretory System
- Birds lack a urinary bladder and urethra, excreting uric acid to conserve water.
- Marine birds possess a specialized salt gland to expel excess salt.
Reproductive Traits
- Birds are oviparous, laying eggs without viviparity or internal live births.
- Unique among vertebrates for their reproduction methods.
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Description
Test your knowledge on Class Aves with this quiz based on Chapter 19. Explore the classification, evolution, and characteristics of birds, including their origins from theropod dinosaurs. Perfect for students studying biology or ornithology!