through here and end up in the [ __ ] Mason
this is the true stomach uh in the
ruminant herbivores this is where
digestive enzymes are going to kill any
of the escaping microorganisms and
protein digestion is completed with the
enzyme protease
digested material is then going to move
into the small intestine we remember the
first section of the small intestine
it's called the duodenum within the
small intestine
products of microbial digestion
are absorbed and additional fermentation
and absorption can occur in the cecum
Downstream which is at the junction of
the small and the large intestine here
is a great close-up of a massive Cape
buffalo which is chewing its cud with
that side to side jaw motion
kind gut fermentation has just one
gastric chamber there's no rumen with
the hind gut fermenters this is
characterized by horses zebras tapiers
rhinoceroses howler monkeys elephants
Lego morphs hyraxes rodents as well as
some arboreal marsupials
hindgut fermenters
masticate food as they eat they're going
to chew up their food initiating
digestion with salivary enzymes like
salivary amylase
digestion continues by enzymatic
activity in the stomach okay so we're
going to go down the esophagus and
directly in to the simple stomach and
then food is going to move into this
long small intestine as new food is
eaten so unlike the ruminant set
artiodactyls hind gut fermenters they're
not going to regurgitate their food
they're not going to chew their cud so
horses and elephants do not have a rumen
and a reticulum and they do not
regurgitate their food and chew their
cut of course nutrients are absorbed in
the small intestine and then finely
ground particles of food are going to
pass from the small intestine first into
the cecum and larger food particles are
going to move right past the cecum and
into the large intestine and are
eventually passed as feces so this is
important among the hind gut fermenters
the colon the large intestine is the
principal fermentation chamber for
larger species like elephants as well as Horses
Horses
while the cecum is going to be the
primary fermentation chamber for smaller
species like your rodents and your Lego
morphs but again hind gut fermentation
is meaning that the fermentation is
occurring at the end of the alimentary
canal instead of at the four at the
beginning as in foregut fermentation so
foregut versus hindgut fermentation the
two types of fermentation processes that
take place in herbivores have clear
advantages as well as disadvantages for
gut fermentation tends to be very
efficient because
microorganisms begin to break down the
plant material before it reaches the
small intestine where absorption occurs
additionally in four gut fermenters in ruminance
ruminance
the microorganisms from the rumen are
themselves broken down by acids in the
true stomach the
abomasum the resulting material which
then contains the carbohydrates and the
proteins synthesized by those
microorganisms as well as the products
of fermentation are going to move into
the intestines and the colon
another benefit of four gut fermentation
is the microorganisms in the rumen are
going to detoxify many of those harmful
alkaloids in the plants that fog up
fermenters consume in contrast food
passes rapidly into the small intestine
in the hindgut fermenters and is then
mixed with the microorganisms Downstream
in the cecum these animals do not digest
the microorganisms themselves that are
present in the cecum and thus they can't
exploit this potential source of
nutrients in addition hindgut fermenters
must absorb the toxic plant chemicals
into the bloodstream and then transport
those toxins to the liver for
detoxification or sequestration
efficiency May indeed be the trademark
of four gut fermenters of the ruminants
however the hind gut fermenters are able
to process material much more rapidly so
for example food moves through the gut
of a horse and only about 30 to 45 hours
whereas it may take a cow a ruminant 70 to 100 hours to process its food
to 100 hours to process its food Pine gut fermenters efficiently digest
Pine gut fermenters efficiently digest food high in protein because large
food high in protein because large volumes of food can be passed through
volumes of food can be passed through them quite rapidly furthermore High gut
them quite rapidly furthermore High gut fermentation is effective when forage is
fermentation is effective when forage is dominated by indigestible materials such
dominated by indigestible materials such as silica and resins because again those
as silica and resins because again those compounds are going to move quickly
compounds are going to move quickly through their alimentary canals by
through their alimentary canals by bypassing the cecum going right into the
bypassing the cecum going right into the large intestine and then excreted in
large intestine and then excreted in some due to their lowered efficiency
some due to their lowered efficiency hind gut fermenters must eat large
hind gut fermenters must eat large volumes of food in a short amount of
volumes of food in a short amount of time the foregut system is relatively
time the foregut system is relatively slow because food can't pass out of the
slow because food can't pass out of the rumen until it has been ground up into
rumen until it has been ground up into very fine particles the digestive
very fine particles the digestive physiology of herbivores is going to
physiology of herbivores is going to influence both their ecology and their
influence both their ecology and their distribution in a myriad of ways so
distribution in a myriad of ways so ruminants like we see here on the left
ruminants like we see here on the left they're going to benefit most from foods
they're going to benefit most from foods that require
that require optimal efficiency in the digestive
optimal efficiency in the digestive system remember ruminants with their
system remember ruminants with their multi-chambered stomach are far better
multi-chambered stomach are far better at extracting nutrients from plants
at extracting nutrients from plants whereas the best forage for hind gut
whereas the best forage for hind gut fermenters as seen here on the right is
fermenters as seen here on the right is the forage which facilitates speed of
the forage which facilitates speed of digestion so each strategy has its
digestion so each strategy has its advantages for survival in particular
advantages for survival in particular ecological niches
ecological niches for environments where food is limited
for environments where food is limited but of relatively high quality like the
but of relatively high quality like the Arctic tundra this is going to favor
Arctic tundra this is going to favor ruminants such as the musk ox and
ruminants such as the musk ox and Caribou so they're going to have an
Caribou so they're going to have an advantage because they can efficiently
advantage because they can efficiently extract so many nutrients from that
extract so many nutrients from that limited amount of forage but when food
limited amount of forage but when food is of low quality with high fiber
is of low quality with high fiber content like these dried out grasses
content like these dried out grasses here but the food is not limited at all
here but the food is not limited at all in terms of quantity a premium is then
in terms of quantity a premium is then placed on those species that have the
placed on those species that have the ability to process large amounts of food
ability to process large amounts of food quickly so
quickly so parisodactyls can survive live in
parisodactyls can survive live in regions typified by seasonal drought and
regions typified by seasonal drought and poor quality food places where ruminants
poor quality food places where ruminants are not going to be able to process
are not going to be able to process foods fast enough to survive so in short
foods fast enough to survive so in short ruminants have the advantage when there
ruminants have the advantage when there is limited high quality forage because
is limited high quality forage because they have efficient foregut fermentation
they have efficient foregut fermentation kind gut fermenters like the rhinoceros
kind gut fermenters like the rhinoceros here have the advantage when there is
here have the advantage when there is abundant low quality forage because they
abundant low quality forage because they can process so much food so quickly one
can process so much food so quickly one of the most successful groups of
of the most successful groups of herbivores are the gnawing mammals
herbivores are the gnawing mammals namely the rodents and the Lego morphs
namely the rodents and the Lego morphs like the ungulates rodents and Lego
like the ungulates rodents and Lego morphs cannot produce the enzyme
morphs cannot produce the enzyme cellulase so they are reliant upon
cellulase so they are reliant upon fermentation of fibrous forage with the
fermentation of fibrous forage with the aid of bacteria and protozoa they have
aid of bacteria and protozoa they have to have those microorganisms in their
to have those microorganisms in their guts as with the parisodactyls rodents
guts as with the parisodactyls rodents and legomorphs do not ruminate they
and legomorphs do not ruminate they don't have a rumen they don't chew their
don't have a rumen they don't chew their cud
cud hind gut fermentation in the rodents of
hind gut fermentation in the rodents of Lego morphs is going to occur primarily
Lego morphs is going to occur primarily in the cecum as well as the colon within
in the cecum as well as the colon within the diverse order rodentia variation in
the diverse order rodentia variation in the morphology of digestive systems is
the morphology of digestive systems is correlated with diet so for example
correlated with diet so for example squirrels Chipmunks and marmots they
squirrels Chipmunks and marmots they feed on a wide variety of seeds nuts
feed on a wide variety of seeds nuts fruits and herbs and therefore they have
fruits and herbs and therefore they have a much simpler digestive system than
a much simpler digestive system than grass eating voles and Lemmings as
grass eating voles and Lemmings as pictured here do hamsters pocket gophers
pictured here do hamsters pocket gophers pocket mice and squirrels have cheek
pocket mice and squirrels have cheek pouches that open near the angle of the
pouches that open near the angle of the mouth so cheek pouches are well adapted
mouth so cheek pouches are well adapted for carrying food as an example cited in
for carrying food as an example cited in your book Allen in 1938 reported 32
your book Allen in 1938 reported 32 beechnuts found in the cheek pouches of
beechnuts found in the cheek pouches of an Eastern chipmunk which is the species
an Eastern chipmunk which is the species you see here We Now understand that the
you see here We Now understand that the digestion of cellulose in hind gut
digestion of cellulose in hind gut fermenters species with no rumen like
fermenters species with no rumen like the rodents and the Lego morphs occurs
the rodents and the Lego morphs occurs in the cecum because there is no
in the cecum because there is no regurgitation and because these mammals
regurgitation and because these mammals are going to pass their forage through
are going to pass their forage through their alimentary canals so quickly these
their alimentary canals so quickly these mammals can't really process fiber when
mammals can't really process fiber when they first ingest plants their microbial
they first ingest plants their microbial communities simply haven't been
communities simply haven't been established yet as a result we observe
established yet as a result we observe coprophagy or the feeding on feces it's
coprophagy or the feeding on feces it's evolved in the rabbits and the hairs the
evolved in the rabbits and the hairs the Lego morphs rodents shrews and some
Lego morphs rodents shrews and some marsupials remember the cecum is located
marsupials remember the cecum is located Downstream of the small intestine the
Downstream of the small intestine the principal organ of absorption so uh all
principal organ of absorption so uh all those minerals and vitamins like
those minerals and vitamins like essential B vitamins that are produced
essential B vitamins that are produced by the fermentation in the cecum those
by the fermentation in the cecum those are otherwise uh lost uh to the Lego
are otherwise uh lost uh to the Lego morbs they're excreted here
morbs they're excreted here so what that means is the Lego morphs
so what that means is the Lego morphs are going to consume some of their own
are going to consume some of their own feces to allow it to pass through the
feces to allow it to pass through the gut a second time to optimize the uptake
gut a second time to optimize the uptake of essential vitamins and minerals and
of essential vitamins and minerals and to enhance the assimilation of energy
to enhance the assimilation of energy the Lego morphs are going to produce two
the Lego morphs are going to produce two types of feces the first are moist
types of feces the first are moist mucous coated black sequel pellets
mucous coated black sequel pellets excreted and promptly eaten by the
excreted and promptly eaten by the rabbit directly from its own anus as
rabbit directly from its own anus as shown in the diagram
shown in the diagram these pellets these sequel pellets are
these pellets these sequel pellets are stored in the stomach and then they're
stored in the stomach and then they're mixed with the new food
mixed with the new food and they're going to form this
and they're going to form this alimentary Mass the second type of feces
alimentary Mass the second type of feces are hard round feces that are passed
are hard round feces that are passed normally
normally so the frequency of coprophagy and
so the frequency of coprophagy and rabbits they're going to do this usually
rabbits they're going to do this usually twice daily and we see that when we
twice daily and we see that when we prevent coprophagy in laboratory rats it
prevent coprophagy in laboratory rats it resulted in a 15 to 25 reduction in
resulted in a 15 to 25 reduction in growth
growth um so acquiring those nutrients produced
um so acquiring those nutrients produced in the cecum by consuming uh their own
in the cecum by consuming uh their own feces is really important for the growth
feces is really important for the growth and survival of these organisms all
and survival of these organisms all right next we're going to do a quick
right next we're going to do a quick survey of some of the specializations
survey of some of the specializations that we see in herbivores and we'll
that we see in herbivores and we'll start with granivary so herbivorous
start with granivary so herbivorous mammals that consume primarily fruits
mammals that consume primarily fruits nuts and seeds are referred to as
nuts and seeds are referred to as granivorous meaning seed eating so
granivorous meaning seed eating so they're typically equipped with large
they're typically equipped with large external fur lined cheek pouches a keen
external fur lined cheek pouches a keen sense of smell as in the hetero Maya
sense of smell as in the hetero Maya rodents the kangaroo rats The Kangaroo
rodents the kangaroo rats The Kangaroo Mice and the pocket mice they're going
Mice and the pocket mice they're going to represent really the most specialized
to represent really the most specialized seed eaters so the diversity and the
seed eaters so the diversity and the availability of seeds in desert
availability of seeds in desert ecosystems like our own Sonoran Desert
ecosystems like our own Sonoran Desert is really key to the evolutionary
is really key to the evolutionary success of these
success of these heteromyads the kangaroo rats and mice
heteromyads the kangaroo rats and mice in terms of the biomass of seeds they
in terms of the biomass of seeds they harvest heteromyans are really rivaled
harvest heteromyans are really rivaled only by ants in terms of being the most
only by ants in terms of being the most important granivores inhabiting North
important granivores inhabiting North American deserts so rodents are reported
American deserts so rodents are reported to use over 75 percent of all seeds
to use over 75 percent of all seeds produced at certain Mojave and
produced at certain Mojave and Chihuahuan Desert sites as a result of
Chihuahuan Desert sites as a result of all those abundant seed resources as
all those abundant seed resources as well as competition with those ants and
well as competition with those ants and birds and other rodents the heteromyots
birds and other rodents the heteromyots those kangaroo rats and mice they've
those kangaroo rats and mice they've evolved fascinating morphological and
evolved fascinating morphological and behavioral adaptations to optimize their
behavioral adaptations to optimize their foraging success so they employ large
foraging success so they employ large cheek pouches to collect as many seeds
cheek pouches to collect as many seeds as possible in single foraging bouts and
as possible in single foraging bouts and then all of these heteromyots are going
then all of these heteromyots are going to cash their seeds they're going to
to cash their seeds they're going to collect large quantities of seeds and
collect large quantities of seeds and they're going to store them in larders
they're going to store them in larders within their bows or scatter and hoard
within their bows or scatter and hoard them in small buried caches outside of
them in small buried caches outside of their Borough all around their territory
their Borough all around their territory so this is a photograph of a kangaroo
so this is a photograph of a kangaroo rat Larder this is it's cash where it's
rat Larder this is it's cash where it's storing all of those seeds for a rainy
storing all of those seeds for a rainy day animals that exhibit adaptations for
day animals that exhibit adaptations for consuming leaves stems Buds and other
consuming leaves stems Buds and other green portions of plants are referred to
green portions of plants are referred to as folivaris meaning the leaf eaters
as folivaris meaning the leaf eaters only about four percent of mammals
only about four percent of mammals specialize in the consumption of leaves
specialize in the consumption of leaves and stems like grazing and browsing
and stems like grazing and browsing mentioned earlier consuming leaves and
mentioned earlier consuming leaves and stems requires considerable
stems requires considerable morphological adjustment in dentition
morphological adjustment in dentition jaw musculature and of course gut
jaw musculature and of course gut morphology leaves are difficult to
morphology leaves are difficult to digest and they have poor nutritional
digest and they have poor nutritional value and in response to predation of
value and in response to predation of leaves by herbivores many of these
leaves by herbivores many of these plants have evolved diverse chemical
plants have evolved diverse chemical defenses like toxic phenols and terpenes
defenses like toxic phenols and terpenes in spite of these obstacles three
in spite of these obstacles three species of marsupials subsist on
species of marsupials subsist on seemingly unpalatable leaves of
seemingly unpalatable leaves of eucalyptus trees koalas uh pictured here
eucalyptus trees koalas uh pictured here as well as the greater gliders and the
as well as the greater gliders and the common ring-tailed possums in eastern
common ring-tailed possums in eastern Australia
Australia for Livery is represented in about 12 of
for Livery is represented in about 12 of the primate General within this group uh
the primate General within this group uh notable full of Wars include the
notable full of Wars include the injuries the howler monkeys the langers
injuries the howler monkeys the langers uh of course the gorillas pictured here
uh of course the gorillas pictured here the colobus and leaf monkeys of Africa
the colobus and leaf monkeys of Africa and Asia the diet of gorillas actually
and Asia the diet of gorillas actually the largest of all primates is going to
the largest of all primates is going to consist of about 86 percent leaves
consist of about 86 percent leaves shoots and stems and then lastly on the
shoots and stems and then lastly on the bottom right we have the two and three
bottom right we have the two and three toed sloths of South America that feed
toed sloths of South America that feed almost exclusively on leaves stems and
almost exclusively on leaves stems and fruit and let us not forget the giant
fruit and let us not forget the giant panda who is well known for its
panda who is well known for its consumption of bamboo shoots so the
consumption of bamboo shoots so the carnassial teeth of pandas are well
carnassial teeth of pandas are well adapted for crushing and slicing up
adapted for crushing and slicing up fibrous plants but because bamboo is so
fibrous plants but because bamboo is so low in nutritional value giant pandas
low in nutritional value giant pandas are going to spend about 12 hours a day
are going to spend about 12 hours a day consuming up to 40 kilograms that's over
consuming up to 40 kilograms that's over 80 pounds of bamboo and yet they're
80 pounds of bamboo and yet they're going to digest less than 20 percent of
going to digest less than 20 percent of what they eat much of the stem is passed
what they eat much of the stem is passed through the gut relatively unchanged
through the gut relatively unchanged mammals that exhibit adaptations to
mammals that exhibit adaptations to consume a diet of fruit which of course
consume a diet of fruit which of course is the reproductive part of the
is the reproductive part of the flowering plants are referred to as
flowering plants are referred to as frugivorous meaning the fruit eating
frugivorous meaning the fruit eating mammals so mammals from several families
mammals so mammals from several families are known to specialize in the
are known to specialize in the consumption of fruit the old world fruit
consumption of fruit the old world fruit bats or the flying foxes as pictured
bats or the flying foxes as pictured here as well as the new world leaf-nosed
here as well as the new world leaf-nosed bats the cuscuses and brushtail possums
bats the cuscuses and brushtail possums uh which we covered already tree shrews
uh which we covered already tree shrews primates such as lemurs lorises many old
primates such as lemurs lorises many old world monkeys Calibus monkeys as well as
world monkeys Calibus monkeys as well as our closest Cousins the chimpanzees and
our closest Cousins the chimpanzees and bonobos
bonobos as fruit can have a hard outer covering
as fruit can have a hard outer covering the teeth of some of these frugalores
the teeth of some of these frugalores are adapted for piercing and crushing uh
are adapted for piercing and crushing uh through that skin of the fruit insects
through that skin of the fruit insects and hummingbirds are not the only
and hummingbirds are not the only animals that have evolved to exploit
animals that have evolved to exploit nectar in fact some mammals are also
nectar in fact some mammals are also exquisitely adapted to capitalize on
exquisitely adapted to capitalize on this resource to take advantage of high
this resource to take advantage of high caloric nectar and in the process spread
caloric nectar and in the process spread the pollen of the host plant
the pollen of the host plant so nectar Rivery meaning nectar eating
so nectar Rivery meaning nectar eating mammals are represented by about six
mammals are represented by about six Genera of bats as well as the marsupial
Genera of bats as well as the marsupial honey possums their skulls are
honey possums their skulls are characterized by elongated snouts small
characterized by elongated snouts small weak teeth poorly developed jaw
weak teeth poorly developed jaw musculature however their tongues are
musculature however their tongues are long and slender and protrude as shown
long and slender and protrude as shown here to access that high caloric nectar
here to access that high caloric nectar and they typically have a brush tip and
and they typically have a brush tip and then they have many rows of these hair
then they have many rows of these hair like papillae pointed back towards the
like papillae pointed back towards the throat as shown here shockingly there
throat as shown here shockingly there are even some mammals that consume
are even some mammals that consume primarily the exudes of trees such as
primarily the exudes of trees such as resins sap or gums and they're termed uh
resins sap or gums and they're termed uh gumiverus meaning gum eating mammals so
gumiverus meaning gum eating mammals so this peculiar diet occurs in eight
this peculiar diet occurs in eight species of marmosets the bush babies the
species of marmosets the bush babies the potatoes the slow lorises four species
potatoes the slow lorises four species of the Peta urid gliders the wrist
of the Peta urid gliders the wrist winged gliders marsupial gliders as well
winged gliders marsupial gliders as well as the lead Butters possum all members
as the lead Butters possum all members of the dwarf and mouse lemurs are going
of the dwarf and mouse lemurs are going to feed on tree exudes so the diet of
to feed on tree exudes so the diet of the uh Fork marked mouse lemur of
the uh Fork marked mouse lemur of Madagascar pictured here consists of
Madagascar pictured here consists of close to 90 percent its diet is 90
close to 90 percent its diet is 90 percent gum from the Trunks and branches
percent gum from the Trunks and branches of trees animals that consume fungi
of trees animals that consume fungi mushrooms and such are referred to as
mushrooms and such are referred to as mycophagus meaning fungus eating so it's
mycophagus meaning fungus eating so it's noteworthy that about 22 species of
noteworthy that about 22 species of primates consume fungi including
primates consume fungi including marmosets gorillas bonobos macaques
marmosets gorillas bonobos macaques vervet monkeys mango bees and this guy
vervet monkeys mango bees and this guy the
the snub-nosed monkey whose diet is actually
snub-nosed monkey whose diet is actually composed of 95 five percent mushrooms so
composed of 95 five percent mushrooms so fleshy fungi are about 70 to 90 percent
fleshy fungi are about 70 to 90 percent water but they do provide a great source
water but they do provide a great source of protein and phosphorus to the
of protein and phosphorus to the consumer and then below ground those
consumer and then below ground those sporal carbs are reported to have very
sporal carbs are reported to have very high concentrations of nitrogen vitamins
high concentrations of nitrogen vitamins and other minerals the vast majority of
and other minerals the vast majority of mammals are omnivorous meaning
mammals are omnivorous meaning everything eating I certainly feel that
everything eating I certainly feel that way and mammals are notably
way and mammals are notably opportunistic so each order of mammals
opportunistic so each order of mammals contains omnivorous species however
contains omnivorous species however omnivore is best Illustrated in the
omnivore is best Illustrated in the opossums the primates including you and
opossums the primates including you and I the humans uh pigs bears like this sun
I the humans uh pigs bears like this sun bear here as well as raccoons the
bear here as well as raccoons the dentition of omnivores is versatile it's
dentition of omnivores is versatile it's adapted to process a variety of foods as
adapted to process a variety of foods as you would expect on the Universe mammals
you would expect on the Universe mammals are going to retain piercing and ripping
are going to retain piercing and ripping cusps in the anterior teeth but
cusps in the anterior teeth but typically have flat broad cheek teeth
typically have flat broad cheek teeth with bunodont cusps that are adapted for
with bunodont cusps that are adapted for crushing food the stomachs of omnivores
crushing food the stomachs of omnivores such as pigs are comparatively simple
such as pigs are comparatively simple the cecum of most omnivores is poorly
the cecum of most omnivores is poorly developed due to the lack of fibrous
developed due to the lack of fibrous plant material in the diet
plant material in the diet Q 58 slides I believe that is a new
Q 58 slides I believe that is a new record uh for us Pat yourselves on the
record uh for us Pat yourselves on the back Round of Applause you've done it I
back Round of Applause you've done it I hope you enjoyed all of the beautiful
hope you enjoyed all of the beautiful pictures and I promise you our last
pictures and I promise you our last lecture for the week is considerably
lecture for the week is considerably shorter thank you so much for your time
shorter thank you so much for your time cheers
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