wildlife biology lecture 3

mammals

what are the 3 orders of mammals in Australia

monotremata

subclass theria

• marsupiala

  • placentia

what are the 4 families of marsupials

diprotodontia (koala, wombat, possums, macropods)

dasyuromorphia (carnivorious marsupials)

peramelemorphia (bandicoots and bilbies)

notoryctemorphia (marsupial moles)

what are the native terrestrial placental mammals

order chiroptera (bats)

order rodentia (rodents)

how many extant species are there

there are 317 extant species representing 6-7% of the worlds population of mammals

what is gondwana heritage

evolved form fauna that was already present on gondwana

monotremes - 100 mya

marsupials - 65 mya

what are the 3 ways mammals became present in Australia

Gondwana

arrived from other continents in waves

introduced

what animals arrived from other continents in waves

eutherian mammals

old endemics

• bats (55 mya)

• rodents (4-5 mya)

new endemics

• rodents (rattus group 1-2 mya)

what species were introduced

recent eutherians - dingoes, rabbits, foxes, cats, house mouse, black rat, pigs, horses, goats, donkeys, camels, feral cattle, deer

how do we know monotremes have gondwanan distribution

fossils have been pound in patagonia, south america

where did marsupials originate

originated in north america about 110 mya with a true fossil identifies 98 mya

when and how did marsupials arrive in australia

Dispersal via Antarctica to Australia (55-65 mya)

where did bats come from

asia and new guinea

how did muric rodents get here

island hopping from south asia

when did the pseudomys arrive

4-5 mya

when and how did dingoes arrive

about 1200 - 3500 years ago probably on boats

how many extant species of monotremes are there

5 species

what does the platypus eat

aquatic invertebrates

where is the platypus native to

east coast of australia in forests with streams

what animals are in the tachyglossidae family

short beaked echidna

long beaked echidna

ornithorhynchidae family

platypus

what is unique about echidnas and platypus

lay eggs- oviparous

no teats for lactation

sophisticated electrosensory system

what is unique about marsupial reproduction

short gestation

extremely small size at birth

forelimb are well develops for climbing from cloaca to pouch

what are some differences between marsupials and eutherians

marsupials have 2 large vacuities

nasal bones widen at the back

marsupials have a greater number of incisor and molars and fewer premolars

what are the 2 orders or marsupials and their groups

diprotodonts ( koala, wombat, possum, macropods)

polyprotodonts

• Dasyuromorphia (carnivorous marsupials)

• paramelephoria (bandicoots and bilbies)

  • notoryctemorphia (marsupial moles)

what is up with diprotodont toes

they have syndactly so the second and third toe are fused

4th toes is elongated to account for hopping gait

how many upper incisors do diprotodonts have

1-3

how many incisors do polyprotodonts have

4-5 upper and 3-4 lower

what is unique about polyprotodont feet

didactyl excep in bandicoots

how many incisors do rodents have

1 pair of incisors

what are the informal grouping of rodents

australo - papuan old endemics

australo - papuan new endemics