Flashcards in Mammals and Flight Deck (32):
What are the similarities between Dimetrodon and homosapiens?
Both have a single opening in the skull behind the orbit.
Evolution of jaw bones to become the malleus, incus and stapes.
Development of secondary palate.
Evolution of glandular skin and hair.
What was lactations original function thought to have been and what is its function now?
To keep eggs moist but now lactation is provide young with nutrition.
Where is milk secreted from?
Specialised mammary glands.
What period was lactation evolved in?
How do monotremes have young?
How do monotremes feed their young?
Milk is secreted from pores in the abdomen and is licked from fur by young.
What is the body temperature of a monotreme?
32 degrees celcius.
How many monotreme species are there and where are they found?
Five extant species found in Australia and New guinea.
Describe the features of a duck billed platypus.
Electro sensitive beak.
Grinding pads to crush food.
Poison spur on ankle.
Paddle like tail.
How do Marsupials have young and how do they raise them?
Vivipary birth (live birth)
Young are born very young like an embryo.
Short gestation time due to yolk like placenta in mother and they're reared in pouches.
Where are Marsupials found?
Australia and Americas.
How many species of Marsupial are found in S. America and in Australia?
S. America - 100 spp
Australia - 230 spp.
Why are young from placental mammals more developed at birth?
Development is allowed by direct feeding through mothers placenta.
What does the placenta provide?
Nutrition, waste disposal, antibodies and produces hormones.
How many species of placental mammals are there and when did most of them come about?
More than 5,300 species in 20 orders. Most major groups are diverged within a short time period during an explosive adaptive radiation.
When did primates evolve?
Evolved from insectivores pre-cretaceous mass extinction 6 million years ago.
What did primates evolve?
Grasping feet with opposable thumbs and big toes with a nail rather than a claw.
What primates are Prosimians?
Lemurs and Lorises.
What primates are Anthropoids?
Tasiers, New world monkeys, old world monkeys, apes and humans.
How much bamboo does a golden bamboo lemur eat in a day?
How much cyanide can a golden bamboo lemur withstand in comparison to other animals its size?
12 times more than other animals its size.
What are the differences between new world and old world monkeys?
Old world: Down turned
New world: Splayed to sides.
NW: Black and white (except howler)
NW: Not padded
OW: Less monogamy and male parental care.
NW: More monogamy and male parental care.
What is an apes anatomy influenced by?
Brachiation - a method of locomotion where an animal swings hand over hand between branches.
What are the adaptations for aerial living?
Flight, gas exchange and navigation.
What is a male dyak fruit bat unique for doing?
Lactating for young.
What are the 5 main hypotheses for flight evolving?
Help escape from predators.
Help catch speedy prey.
Help assist longer transits from place to place.
Free hind legs for use as weapons.
Gain access to new food sources or an unoccupied niche.
What helps migrating birds in the air?
Aerofoils which creates a lift making air flow faster over the aerofoil due to low pressure.
Why was the evolution of a complex gas exchange mechanisms driven by aerial flight?
Because of the need for rapid gas exchange due to the high energetic cost of flight.
Describe avian 'flow through' the lungs.
Inhalation: Fresh air is inhaled into the first chamber.
Exhalation: Air is pushed across the lungs, where oxygen transfers over into the blood stream (carbon dioxide transfers into the lungs)
Inhalation: Air, now deoxygenated, is pushed into the second chamber.
Exhalation: Deoxygenated air is exhaled out again.
What is magnetoception and what does it allow an organism to do?
A sense which allows an organism to detect a magnetic field and allows them to percieve direction, altitude and location.
Why does magnetoception work?
Magnetite crystals respond to magnetic fields.