Herbert Flashcards
Four traits that distinguish mammals from reptiles?
Homeothermic
Suckling of young
Body hair
Muscular diaphragm
What is the difference between prototheria, metatheria, and eutheria?
Prototheria- egg layers (monotremes)
Metatheria- embryonic young (marsupials)
Eutheria- birth more developed young
What are the origins of marsupials and monotremes?
Breaking off from Antarctica 35-40 million years ago
What are the origins of Australian eutherians?
Island hopping 5-6 million years ago
What are the most easily recognisable differences between ameridelphia and australidelphia?
Structure of the tarsal bones
Also blood proteins, DNA and sperm morphology
What are the four orders of marsupials?
Dasyuromorphia
Peramelemorphia
Diprotodontia
Notoryctemorphia
What is the name of the opposable 1st digit on the hind foot present in some marsupials?
Hallux
Define polyprotodont
Multiple pairs of lower incisors
Define diprotodontia
One pair of incisors in the lower jaw.
Define syndactyly
Normal occurrence of having two or more fused digits in a mammal species.
Between what two digits is syndactyly most common?
II and III
What is the dentition of dasyuromorphids?
Polyprotodont
Would a spotted quoll have one or more digits fused together naturally?
No, it is a dasyurid, they do not have any syndactyly
Bandicoots have three pairs of equal sized lower incisors.
Yes they are of the order peramelemorphia which are polyprotodonts
Syndactyly is a defining aspect of peramelemorphia
True/ False
True
What does the order notoryctemorphia include?
Marsupial moles
All diprotodonts have one pair of lower incisors
True or false?
True
What order do koalas belong to?
Diprotodontia