Lecture 24: Amniotes Part 2 Flashcards
What is the key defining feature of Synapsids?
They only have one set of holes in their skull
What non-mammalian members are in the Synapsids?
Sailbacks - dimetrodon
some therapsida
What dose the root word -ther- mean?
Beast.mammal
How did most Synapsids walk around in early spp?
they had a sprawling, reptile like gait
what was the mode of eatting for early Synapsids
they were mostly predatory
What is the defining characteristic of Therapsids?
they had a enlargement of the dentary bone in the jaw
and they show development of secondary plates
What are the main characteristic of mammalians?
The movement of leftover jawbones to the middle ear
True or false:
Mammalian detection is far more differentiated than that of the reptilia
True.
True or false:
Mammalians have a far more diverse diet than that of the reptilia.
True
True or false:
Reptilia teeth occlude more closely than that found in the mammalians
False.
Mammalians teeth are more closely occluded
What are the characteristics of Mammalian teeth?
They have 2 sets of teeth over their lifespan (milk teeth and adult teeth)
What is the placement of extant mammals limbs?
More ventical placement of limbs
What are three major defining features of Mammalians?
They have hair
They are endothermic and homeothermic
they have a diaphragm
What are the Mammary glands of mammalians used for?
They are used for producing milk
What dose the root word _mamma- mean?
breast
What are the three major clades of extant mammals?
Order Monotremata (clade with only one order) Oder Marsuplialia (Clade with only one order) Clade Eutheria (has many orders)
When did mammals first diversify?
After the mass extinction event at the end of the cretaceous period.
What are the extant species of Monotremata?
1 platypus
4 echidna
What is the defining characteristic of Monotremata?
they lay eggs and provide milk to their young
Do Monotermata have a Cloacas?
Yes
What dose the term Mono mean?
1
What dose the root word -terma- mean?
Hole
What is the defining features of the Theria?
They give birth to live young
young are nourished through the placenta initially then nursed on milk from nipples
What is the defining feature of the Order Marsupialia?
The embryo crawls into the mother pouch
What dose the root word -marsupium- mean?
pouch
Do Marsupialia have a cloaca?
Yes
What is the defining feature of the eutherians?
They are non-marsupial therians
How do eutharia nourish their young?
Through the placenta until well developed.
How do Eutharia feed their young
From a number of nipples
Do Eutharia have a cloaca?
Nope
Where did the Afrotheria undergo diversification?
in Africa
What are the most well known Xenarthra?
Anteaters, sloths, armadillos
What is the defining feature of Xenarthra?
They lack teeth (most of the time)
They have a extra articulation in their vertebrae
What dose the root word -xenos- mean?
strange
What is the origin of the clade Laurasiatheria?
The name comes from a super continent that once comprised Europe, Asia, and north America
What is the most well known order included within Laurasiatheria?
Carnivora
Chiroptera
What is the most well known member of the Order Chiroptera?
Bats
What is unique about Order Chiroptera?
They are the only mammalians with powered flight.
Chiroptera use ______ to augment sight
Sonar
What is killing off loads of Chiroptera?
White nose syndrome
are hoofed mammals included in Laurasiathera?
Yes they are
Is Cetartiodactyla included in Laurasiathera?
Yes it is
it includes whales and dolphins
What is the defining feature of the Order perissodactyla?
They are odd toed
What is the most well known member of the order Lagomorpha?
Rabbits and hares
what is the most well known member of the order Rodentia?
Rats and mice
What is the largest order of mammals?
Rodentia
What is the defining characteristic of rodentia?
They have constantly growing teeth
What is the most well known member of the order Scandentia?
the tree sherws
What is the sister taxa to scandentia?
Primates
