Studied by 1 personWhen do birds first appear in the fossil record?
Jurassic Period
Roughly how many species of birds are there?
10,000
Which dinosaur are birds closely related to?
Velociraptor (Theropod dinosaur)
What is the first known bird in the fossil reccord?
Archaeopteryx
What species appears to be a Theropod specialized for flight?
Archaeopteryx
Was the Archaeopteryx a reptile with bird-like features?
No, it was a bird with reptile-like features
What reptile-like features did the Archaeopteryx posses?
Reptile-like head with teeth and scales, and a well developed tail with vertebrae
When did birds radiate during the fossil record?
Tertiary Period, early Cenozoic Era
What was a large predatory bird from the Tertiary Period?
Gastronis
Where have terror bird skeletons been found?
North America from Central Florida to Texas
What are "pneumatic" bones?
Hollow bones
What portion of the birds body provides a strong structure for wing attachment?
Trunk portion of the bird's skeleton forms a "rigid airframe"
What are the braces found in birds between the ribs?
Uncinate Processes
What is the name of the group of flightless, keel-less birds?
Ratites
How many toes do birds usually have?
4 toes (with 3 forward and 1 backward)
How are the feet of roadrunners adapted for running?
They have 2 toes forward and 2 toes backward
What are feathers derived from?
Highly modified reptilian scales
Are bird feathers homologous or analogous to reptilian scales?
Homologous
What are feathers composed of?
Keratin
What organisms also appeared to have feathers? (other than birds)
Theropod dinosaurs
What are the functions of feathers?
Flight Insulation Buoyancy Camouflage Advertisement and display
Do birds have scales?
Yes, on their legs and feet
Are birds cold blooded or warm blooded?
Warm blooded (endotherms/homeotherms)
What group of organisms are the warmest of the vertebrates?
Birds
Do birds have a muscular diaphragm?
No
Are birds positive or negative pressure breathers?
Negative pressure breathers
How do birds move air through their lungs?
They move their wings, ribs, and sternum
What type of air flow do birds exhibit?
Unidirectional air flow through the lungs
Does the larynx produce sound in birds?
No, their syrinx (at bottom of the trachea) produces the sound and the larynx just modifies it
Are birds songs sung by the males or females?
Males, often stimulated by the hormone testosterone
What are bird calls used for?
They are used as alarm calls or to maintain contact with other birds
Do birds have nostrils?
Yes, they have small holes in their beaks for nostrils
What is an example of a bird with good olfaction?
Kiwi, its nostrils are at the tip of its bill so it probes soil with its long beak and smells for food
Do birds have Loops of Henle in the nephrons of their kidneys?
Some birds have loops of henle to concentrate their urine
What nitrogenous waste product do birds produce?
Uric acid (humans produce Urea)
Why is guano from birds mined off of islands?
It is rich is nitrogen and phosphates
Do birds have salt glands?
Yes, located just above the eye in most sea birds to get rid of excess salt
Are all birds oviparous?
Yes, all birds are egg laying
Do all birds have paired gonads?
No, only the left ovary develops in most birds
Why do female birds only have one ovary?
To reduce weight for flight
What type of fertilization do birds use?
Internal fertilization
What is the difference between altricial and precocial hatchlings?
Altricial - born naked, helpless Precocial - born with feathers, independent
Why are North American areas good breeding locations for birds during the spring/summer?
Fewer predators Large supply of insects in summer More time to feed
When do mammals first appear in the fossil record?
Triassic Period (start of the Mesozoic), small insectivors
How many living species of mammals are there?
Approximately 5450 species
Which group are the mammal-like reptiles?
Therapsids
When did mammals begin to radiate in the fossil record?
Tertiary Period
Are the marsupials the most successful group of mammals?
No, the placental mammals are the most successful group of mammals
What is the advantage of hair in mammals?
Provides insulation
Which is a better insulator hair or feathers?
Hair
Are horns or antlers shed annually?
Antlers, horns are retained throughout life
Are antlers grown by males, females or both?
Only males
Are horns grown by males, females or both?
Both
What is unique about Rhinoceros horns?
They are composed of hair-like fibers that adhere/cement to one another, both sexes have them
Which family has "true horns"?
Family Bovidae ("ruminants" such as cattle, sheep, antelope, etc.)
What family has antlers?
Family Cervidae (deer family: deer, elk, moose, caribou)
What types of glands does mammal skin have?
Sweat, sebaceous, scent, and mammary glands
What hormone(s) stimulate mammary gland growth?
Estrogen and progesterone
What hormone stimulates milk production?
Prolactin
What hormone stimulates milk ejection/milk let down?
Oxytocin
Are placental mammals the warmest of the vertebrates?
No, the birds are the warmest
What is the name of the "newer, more advanced" cerebral cortex seen in mammals?
Neopallium
What is the cerebellum used for in mammals?
Complex motor movements
Are elephant tusks highly modified canine teeth?
No, they are modified incisors
Are walrus tusks modified canine teeth?
Yes
Are Wild Boar and Javalina tusks enlarged incisors?
No, they are enlarged canine teeth
What teeth are modified in the Vampire bat so they can make incisions to retrieve blood from their prey?
They have modified incisors
Which incisor is modified in Narwals?
Their upper left incisor
Do both male and female Narwals have a large tusk?
No, males only
Do carnivores have a short or long digestive tract?
Short, to prevent fermentation
Do herbivores have a short or long digestive tract?
Long, for absorption of nutrients
Do mammalian kidneys have Loops of Henle in their nephrons?
Yes, they can concentrate their urine
Are mammals positive or negative pressure breathers?
Negative pressure breathers
Do mammals have a muscular diaphragm?
Yes
What is the most primitive group of living mammals?
Monotremes
What is unique about the monotremes in comparison to the other mammals?
They are oviparous (egg-laying), and have a cloaca but no nipples
How many living species of monotremes are there?
3 living species (Duck-billed Platypus, Long-nosed Echidna, and Short-nosed Echidna)
Placental mammals and marsupials have similar niches, this is hypothesized to be what type of evolution?
Convergent evolution
What is unique about Kangaroo reproduction?
They can simultaneously have 3 different young at various stages of development (i.e. embryo in uterus, fetus in marsupium, and joey)
When are the first placental mammals found in the fossil record?
Tertiary Period
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