Mammals Flashcards
What is a cursorial mammal
A running animal
What is a fossorial mammal?
A burrowing animal
How many species of mammal are there?
4800, mammals are the LEAST diverse clade
What is prototheria?
The monotremes
What is metatheria?
The marsupials
What is eutheria?
The placental mammals
What are the 5 unique mammalian characteristics?
- Hair for endothermy
- Lactation
- 3 middle ear bones
- Significantly enlarged brain
- Diphyodonty (2 sets of teeth)
What is theria?
A clade containing metatheria and eutheria
Which group is the only group to have nipples?
Theria (the marsupials and placentals)
What do monotremes have instead of nipples?
Mammary hairs
What is the mammalian stapes homologous to in reptiles?
The columella in the middle ear
What is the mammalian incus homologous to in reptiles?
The quadrate
What is the mammalian malleus homologous to in reptiles?
The articular
How many species of prototherian are there and what are they?
5:
1 platypus and 4 echidna
The prototherians have a single posterior opening, what is it called?
The cloaca
What can platypuses sense with their snouts?
Electromagnetic signals
How many eggs do prototherians usually lay?
1-3
What are the eggs of prototherians like?
Leathery eggs
How many species of metatherian are there?
270
Why are metatherians born at such a low birth weight?
The young are born as foetuses with overdeveloped forelimbs to crawl to the pouch. There they latch onto a nipple and develop outside the body.
What are the didelphimorphia?
The American opossums
What are the paucituberculata?
American shrews
What are the microbiotheria?
South American monito del monte
What are the dasyuromorphia?
Carnivorous Australian marsupials
What are the peramelamorphia?
Australian bandicoots and bilbies
What are the notoryctemorphia?
Australian me arsupial moles
