meaning uh burrowing marsupials that are herbivorous
herbivorous
so all that said there is an outstanding
array of Behavioral and morphological
adaptations that characterize the the
seven orders of the marsupials so think
kickboxing kangaroos the koala bear
which has evolved A specialized diet
feeding on only eucalyptus the
incredible bite force of the Tasmanian devil
devil
and at least we not forget the cube
so for the remainder of the lecture
we're going to quickly survey each of
those seven orders and many of the
families let's begin with the order die
delpha morphia which includes the single
extant family
diedelfa day so these are the new world
or American
opossums there are 18 Genera remember
that's the plural for genus there are 18
General and 111 species in the family uh
didelpha day
let's see uh the didelphids are
characterized by their tails most have
this long sparsely haired prehensile
tail a prehensile tail is going to allow
the animal to hold on to and manipulate
objects almost like an additional arm
it's going to allow your arboreal
opossums to hang from their tails to
grasp tree branches uh while they forage
and then they're also characterized by
an opposable thumb which again
accommodates uh many of their
semi-arboreal or arboreal habitats the arboreal
arboreal
bushy-tailed opossum is found in humid
tropical rainforests in Ecuador Peru
Bolivia and Brazil there are three
species of woolly opossums that are
Forest inhabitants of southern Mexico
Central America and North Central South
America and then we have the diminutive
10 to 15 gram calendar oscares Mouse
opossum which is adenosine of lowland
forests in Amazonia so several
deidelphids like this yellow-sided
opossum here on the left show similar
parity symbol parody is a life history
strategy in which all or most of the
males die after mating and then the
females die after weaning their young
the most specialized didelphid is the
yapark or the water opossum so this is
the only marsupial that's adapted for an
aquatic habitat and a diet of small
vertebrates so the hind feet of the
epoch are webbed and then the females
marsupium is going to seal and become
impenetrable to the water keeping her
young safe while she Dives which leads
us to the Virginia opossum didelphis
Virginia and this week's discussion prompt
prompt
many mammals such as the Virginia
opossum are known to produce more young
than can be supported by the number of
the mothers Mame or teats this attribute
seems maladaptive explain this apparent
waste of energy
to help comment intelligibly on this
post please listen to the stated clearly
video I've embedded in canvas that's
entitled survival of the fittest what
does it really mean
the order Posse tuberculata contains
just a single family that can no less
today which is comprised of three Genera
and seven species of shrew or rat
opossums of course shrews and rats are placentals
placentals
the five species of cannolestes occur in
dense vegetation and cold wet high
elevation forests and Meadows of
Northwestern South America the cane
listids are primarily nocturnal
insectivorous or omnivorous and to rest
the single family and this order the
microbiotheria contains only one extant
species and that is the monito Del Monte
the little monkey of the mountains the
monito Del Monte is nocturnal it's
clearly arboreal it inhabits temperate
rainforests in South Central Chile and
adjacent Argentina
so prior to hibernation this species
accumulates fat at the base of its
prehensile tail this is called an
incrassated tail one that has evolved to
store energy as fat reserves it can
store enough fat in just one week to
double its body mass
interestingly this species also exhibits
short periods of daily torpor depending
upon ambient environmental conditions so
torpor is when an organism is capable of
lowering its metabolic rate lowering its
body temperature and this instance this
species is capable of lowering its
metabolic rate by a whopping 92 percent
uh as a frugivore or a fruit eating
mammal the monito Del Monte plays a
crucial ecosystem role in dispersing
native seeds in its feces and then
finally recall from the video how South
America made the marsupials in lecture
1.4 that the monito Del Monte is the
sole living representative from this order
order
microbiotheria which likely represents
the ancestral lineage of all of the
Australian marsupials so this is a
really important Relic species and with
that let's now jump over to the
continent of Australia we'll begin with
the order dazzy euromorphia which
includes three families of carnivorous
and insectivorous marsupials including
the namesake family the dazzy uraday the
mere mecco bidet and the thylacine day
most of these stand species are in this
dazzy uraday family and then with the
extinction of the thylacine the dazzy
urid the tasmanian devil is now the
largest living carnivorous marsupial and
that brings us to the heart-wrenching
tale of the thylacine the thylacine was
often called the Tasmanian Tiger
presumably because of those dorsal
stripes or the Tasmanian wolf but as you
buddy mammologists know the thylacine
was neither tiger nor wolf those are
placentals it was a large carnivorous
marsupial in the order dazzy euromorphia
bilesine fossils have been recovered
from the Australian Mainland Papua New
Guinea as well as Tasmania of course and
further Aboriginal rock art confirms
that the thylacine was in Australia when
the first inhabitants the First Peoples
colonized Australia
by the time the Europeans arrive the
thylacine's range has been greatly
reduced it's restricted only to the
island of Tasmania it's likely that
competition with the dingoes that were
introduced by those original Aboriginal
people was probably a significant factor
in out competing and reducing the
thylacine's range and the species may
have survived in uh to modern times in
Tasmania because dingoes were not
introduced there European settlers
arrived in Tasmania at the beginning of
the 19th century and upon doing so they
set out to tame the Wilderness and
reshape the Tasmanian landscape in the
image of their homelands the thylacine
was perceived as a wolf amongst their
sheep and it acquired this notorious
reputation as a killer of livestock
despite the fact that the settlers dogs
were probably far more destructive
but there was no room for predators and
the Pastoral Paradise envisioned by
these settlers and therefore a bounty
was set to ensure thylacine
extermination the peak of the killing
occurred in 1900
indiscriminate killing coupled with
population fragmentation and habitat
loss caused the thylacine population to
decline rapidly disease may also have
contributed to the demise of this
decimated fragmented population
a few naturalists recognize this
precipitous decline of this really
amazing species But ultimately the
concerns of the ranchers took precedence
the last shooting of a wild thylacine
was documented in 1930 and the last
captive individual shown here died in
the Hobart zoo in 1936. ironically the
same year that the species was granted
legal protection so a little bit too late
late
the thylacine's reputation as a sheep
killer was likely significantly
overstated the thylacine only weighed an
estimated 35 to 40 pounds and its teeth
and limbs suggest that its prey was most
likely to have been relatively small
compared to its body size it likely fed
on bandicoots and possums it probably
hunted its prey in a pounce and pursuit
manner in Fairly open habitats and it
killed with a crushing penetrating bite
that's an impressive Maul right there
the remains of small to medium-sized
herbivores all weighing less than five
kilograms approximately 11 pounds have
been found in cave deposits along with
thylacine remains Hunters reported that
the thylacine stomach contents did
include kangaroo but also Echidna remains
remains
so since the death of the last
individual in the Hobart zoo in 1936
there have been several exhaustive
searches over the decades most recently
in 2017 during which time
580 camera traps were deployed in North
Queensland by James Cook University
after two people on experienced
Outdoorsman and a former park ranger
reported having seen a thylacine there
in the 1980s but according to reports
they were too embarrassed to tell anyone
at that time
however according to the Department of
primary Industries Parks water and
environment that's a mouthful there have
been eight unconfirmed thylacine citing
reports between 2016 and 2019 with the
latest unconfirmed visual sighting
occurring on the 25th of February 2018
but as of this recording there has yet
to be a confirmed sighting of the thylacine
thylacine
Psy the family Mir makoba day is
monotypic and includes only the numbat
the numbat is highly specialized for a
diet of exclusively ants and termites so
this is a niche known as Mir
mechophagy this numbat the species is
now restricted to isolated populations
and arid scrub woodlands in Southwestern
Australia as introduced predatory foxes
and feral cats have greatly reduced
numbat populations to likely less than a
thousand individuals the numbat is
listed as endangered by the iucn that's
the international Union for the
conservation of nature the family dazzy
uraday is a large diverse family
including 17 Genera and 76 species the
dazzy urids are the most structurally
and functionally
generalized of the Australian marsupials
deserts range in size from the smallest
marsupials the marsupial mice like you
see here up to the largest marsup
largest carnivore the Tasmanian devil
deserts occur throughout Australia and
New Guinea where they occupy all
terrestrial and semi-arboreal habitats
from deserts to high elevation
rainforests they're primarily Nocturne
journal or crepuscular meaning active at
dawn or Dusk and they're solitary on the
top left is the Tasmanian devil devils
are scavengers that have an ecological
niche comparable to the North American
Wolverine you can see it's got this
really large maw and a very strong jaw I
have some good news about Devils that
I'm going to return to on the next slide
there are six species of coals uh like
this tiger or spotted coal these guys
weigh up to 15 pounds and they're gonna
eat small mammals small birds lizards
and insects all six of the qual species
have drastically declined in numbers
since Australia was colonized by
Europeans with one species the Eastern
qual becoming extinct on the Australian
Mainland and hanging on now only on the
island of Tasmania major threats to Coal
survival include the toxic cane toad
introduced predators of course such as
feral cats and foxes Urban Development
and even poison baiting
The Kangaroo Island done art is also in
trouble it's listed as critically
endangered by the iucn population was
believed to be around 500 individuals
before the horrific
2019-2020 Australian bushfires
so following those fires it's believed
that only about 50 of these Kangaroo
Island gun Arts are left in existence
and we're going to return to those
devastating fires uh later in the
presentation when we discuss koala bears
this is the a brush-tailed mogara it's
kind of cool uh these guys uh have
incrassated tails uh meaning they can
store fat in those tails
so right now uh do me a solid put me on
pause and check out Darwin and the
devil's plight it's about facial tumor
disease that's an infectious cancer that
has just decimated uh Tasmanian Devil
populations however it now appears that
some individuals that are surviving have
resistance to tumor facial disease their
tumors are healing so conservation
success stories can be few and far
between so take one minute and 18
seconds and please check out this video
embedded in canvas [Music]
[Music]
the order Pera melee morphia contains
the Australian Easter Bunny the greater
Bilby or the rabbit-eared Bandicoot as
pictured here the omnivorous bandicoots
occur across the australasia
biogeographic province from arid deserts
all the way up to high elevation
rainforests the family para Melody
includes six Genera and 20 species of
extant bandicoots ranging in size from
the mouse Bandicoot with a maximum
length of just seven inches to the giant
Bandicoot which has a body mass of 11
pounds this striking species is the
Eastern Bard Bandicoot
there are two recognized species of
bilby's the threatened greater Bilby
living in arid habitats in Northwestern
Australia and the Lesser Bilby which
probably became extinct in the 1960s [Music]
[Music]
and these are two very strange species
the order Noto richta morphia
encompasses just a single family the
notoric today which includes the
southern marsupial mole and Northern
marsupial mole so these are the only
completely fossorial or burrowing
marsupials they spend the majority of
their lives underground you can notice
the remnants here of an eye a vestigial
eye these no longer function
these uh marsupial moles are widely
distributed over much of Northwestern
and Central Australia occurring in shrub
desert areas and Sandy bottomed soils
insectivorous their diet consists
primarily of ants termites B larvae and
apparently the occasional centipede
right we've made it to the last order
order dye Proto dantia includes 11
extant families comprised of species
like the koala bear the wombat the
ring-tailed possums the kangaroos my
favorite the cuscuses this is the
feather tail glider and then the pygmy
possums here on the bottom right so
given that this order has
155 recognized species
adaptive radiation has been extensive
some species feed on insects others
nectar still others leaves fruit others
still are omnivores many species are
terrestrial although some are obviously
arboreal my son's favorite animal the
koala bear has a highly specialized diet
so on the menu leaves stems flowers and
even bark all from the eucalyptus tree
so koalas inhabit Eastern and
Southeastern Australian eucalyptus
Woodlands as you would imagine
eucalyptus is very poor quality forage
not a lot of calories but koalas have
reduced energy requirements they move
very slowly and they remain inactive for
up to 20 hours a day truly living the
dream right their alimentary track has
the largest cecum that's the intestinal
pouch at the junction of the small and
the large intestines as the the koalas
have the largest cecum relative to body
size of any other mammal [Music]
[Music]
unfortunately the koala has now been
designated as endangered populations of
koalas have been ravaged by chlamydia
which can cause blindness and
infertility in koalas and then to add
insult to injury the bushfires in the
Australian summer 2019-2020
so gang we are living in the age of
Rapid climate change
fair warning this video is kind of harsh
to watch but I think it's important that
we don't look away so please take three
minutes and check out the embedded video
in canvas entitled koalas need help
surviving Australia's fires produced by
the Family vombata Day includes the two
Genera and three species of wombats
wombats have short limbs their plan to
grade meaning they walk on the soles of
their feet like humans and bears and
they're powerful borrowers these guys
are really big so adult body mass is
about 30 kilograms so that's 66 pounds
that's actually heavier than the thylacine
thylacine
this is a common wombat the bare-nosed
wombat it's found in forested areas of
Southeastern Australia and Tasmania the
southern hairy-nosed wombat inhabits
semi-arid regions of Southern Australia
and then finally there's the critically
endangered Northern hairy-nosed wombat
and it's now restricted to just a 500
hectare portion of epine Forest National
Park and Central Queensland and here's a
pic of one of those hairy nosed wombats
sitting atop of his burrow
wombats are the only marsupial to have
open rooted continuously growing
dentition which makes sense because
they're herbivorous they have a broad
skull as you can see here with robust
jaw muscles and cheek teeth premolars
and molars that are well adapted for
abrasive grasses and forbs on hot dry
days wombats are going to remain in deep
extensive interconnected burrow systems
that protect them from predators and
fires and harsh ambient conditions the
trade-off however is is that the
construction of these burrow systems is
energetically expensive and wombats are
living on grass so their metabolic rate
is extremely low even for a marsupial
and finally I addressed that question
that has undoubtedly been burning in
your mind since the beginning of this
lecture how do wombats poop cubes the
only animal in nature to Mark its
territory with tidy little piles of
fecal cubes so this one's really great
footage and it's only three minutes
please check it out embedded in canvas
as their name implies the pygmy possums
are the most diminutive possums they're
quite small the smallest species has a
mean adult body mass of just seven grams
so that's the equivalent of like seven
regular sized paper clips
in addition to invertebrates fruits and
seeds the pygmy possums are also going
to consume nectar and pollen thus they
have these long extendable brushed
tongues with papillae for lapping up
these floral Delicacies
there are four species of brush tail
possums like the common brush tail
possum seen here on the bottom left and
then there are 25 species of cuscus like
this uh flamboyant spotted cuscus here
who lives in the Bountiful tropical
rainforests of Papua New Guinea like
many of the American uh opossums these
uh brush tail possums and cuscuses are nocturnal
nocturnal
they have long prehensile grasping tails
and they are arboreal the aptly named family
family
acrobatiday includes the feather tail
glider the world's smallest gliding
mammal so the feather tail glider
possesses a furred pathogium that's a
gliding membrane that extends between
the elbows and the knees
there are six Genera and 20 species of
ringtail possums including the species
pictured here the Western ring-tailed
possum this species is critically
endangered due to the drying climate
Urban Development altered fire regimes
and predation by invasive feral foxes
includes four species of possum-like
triox the striped possum the
leadbetter's possum and then six species
of wrist winged gliders like this
adorable sugar glider these arboreal
gliders are named for the patagium that
extends from the wrist to the ankle
similar to the feather tail glider the
marsupial gliders are highly convergent
they have very similar morphology to the
North American gliding squirrels like
glaucomes volants but of course they're
not closely related to the Flying Squirrels
the tiny honey possum is the only
non-flying mammal that feeds exclusively
on nectar and pollen it's adapted to
this lifestyle with a long pointed
Rostrum a tubular mouth and an
extendable brush tipped tongue the musky
rat kangaroo and you gotta love those
common names is monotypic meaning it's
the sole member in its family so this
implies that it's distinct
morphologically genetically from other
there are four Genera and 12 extant
species in the family potorua day
including the long-nosed podoru uh
pictured here interestingly these
omnivores have a penchant for fungus and
lastly that family that you've all
likely been waiting for that family
that's truly emblematic of Australian
Wildlife the macro PO today macro means
large pod is foot the large footed
family of wallabies and kangaroos there
are 13 Genera and 67 extant species in
this family ranging in size from the two
pound hair wallaby here on the left to the
the
175 pound red kangaroos
all living macro podids are herbivores
and they occupy practically all
terrestrial habitats from deserts to
rain forests throughout austral Asia and
let's not forget about the semi-arboreal
tree kangaroos on the bottom right
ecologically and morphologically the
macro potids have evolutionarily
converged into that large herbivorous
Niche occupied by the placental
artiodactyls the deer the Sheep the
goats in other bio regions around the
world so for example kangaroos have
large divided stomachs that are home to
a whole slew of microbes that are
capable of breaking down cellulose so
similar to placenta little cows that
chew their cud red kangaroos will
regurgitate their food for additional
obviously the macropotids have strong
well-developed hind Limbs and large hind
feet but they also have this long broad
tail that actually serves a variety of
functions the tail can be a tripod while
the kangaroos are reaching up and
foraging it can serve as a fifth limb in
what's called Penta pedal Locomotion two
four five Limbs and then lastly that
tail serves as a counter balance during rapid
rapid
bipedal hopping it speeds up to 30 plus
miles per hour
oh and let us not forget how those
strong well-developed hind limbs are
used in male to male combat so for your
final video please please check out
David Attenborough and this amazing
footage of red kangaroo kickboxing so
some of these males are truly
intimidating all right in closing I want
to point out table 10.1 in your textbook
this is the first part of the table and
it summarizes all of the orders and the
families that I covered in this lecture
today so fair warning on your exam this
week you'll be asked to match a handful
of common names to their families and or
orders so I the
Kangaroos and wallabies are in the
family macro PO today in the order die
Proto dantia so I'm asking you please
spend a bit of time and study the
taxonomy presented in this lecture
and as always here are the references
that are also cited in the text and that
I used in this lecture awesome I really
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