Modern Mammals

1
Modern Mammals

• Characteristics of the mammals
• Lactation Feed young on milk
• Hair
• Skeletal features
• Heterodont dentition
• Single jaw bone (dentary).
• Two occipital condyles
• Middle ear with three bones incus, malleus,
  stapes
• Endothermy
• Muscular diaphragm

2
Lactation

• Lactation females of all mammals feed their
  young on milk produced by mammary glands.
• Mammary glands are completely absent from male
  marsupials, but are present in male therians
  (monotremes and placental mammals) and
  potentially functional.
• There are cases of human males producing milk and
  there is a species of fruit bat in which males
  produce milk.

3
Lactation

• Although all mammals produce milk only marsupials
  and placentals have nipples.
• In monotremes the milk seeps from pores in the
  skin and the young suck the milk from the
  mothers fur.

4
Hair

• Hair has a variety of functions.
• Obviously, insulation is its primary purpose.
  Fur is made up of closely placed hairs and the
  insulating value of the fur is a function of its
  length.
• Longer hair allows more air to be trapped and
  this reduces heat loss.

5
Snow leopard http//metastwnsh.files.wordpress.com
/2008/11/calculation-snow-leopard1.jpg
6
Hair

• Hairs can be erected by erector pili muscles that
  attach halfway along the hair shaft.
• This raising of the fur increases the amount of
  air trapped and thus the insulation level. Hair
  may also be raised as a threat or defensive
  display.
• Although humans lack fur we retain the erector
  pili muscles as vestigial structure and these
  produce goosebumps.

7
Hair

• Hair is composed of keratin, a fibrous protein,
  and keratin is also used to make nails, hooves
  and claws.
• Hair coloration is determined by melanocytes in
  the hair follicle that add different types and
  amounts of pigment to the hair as it develops.

8
Hair

• Exposed hair is non-living and bleaches with age.
  
• The replacement of the fur occurs in the process
  of molting in which old hairs are lost and
  replaced by new ones. Most mammals molt their
  hair seasonally once or twice.

9
Molting mountain goat http//ecolibrary.cs.brandei
s.edu/images/ thumb50/thumb50_Mountain_goat_moltin
g_DP4102.jpg
10
Hair

• In addition to acting as insulation hair also
  plays an important role in camouflage.
• The color pattern is the result of the mixing of
  a variety of different colored hairs.
• Hair is also used for communication and threat
  displays often include puffing up the fur.

11
Vibrissae

• Vibrissae (e.g. a cats or a seals whiskers) are
  special hairs that have a sensory function.
• Vibrissae occur on the muzzle and around the eyes
  and they are connected to touch receptors in the
  skin.

12
Cats vibrissae http//upload.wikimedia.org/wikipe
dia/commons/3/39/Cats_whiskers.jpg
13
Claws, nails, horns and hooves

• Keratin is used to make not only hair but nails,
  claws, hooves and horns.
• Claws, nails and hooves are all the result of an
  initial accumulation of keratin to protect the
  bones making up the toe (phalanges) that was
  later modified in ungulates into hooves, which
  entirely cover the entire 3rd phalanx (the
  terminal bone of the toe) and into retractable
  claws in cats

14
http//osnhc.com/images/BASICHOOFANATOMY.jpg
15
Horns

• Horns are also formed at least partially from
  keratin. Rhinoceros horns are made entirely of
  layers of keratin fibers.
• In contrast, the horns of cows and antelopes are
  made up of a keratin sheath over a bony core.

16
White Rhinoceros http//www.mth.msu.edu/peller/Af
rica_large/rhinoceros.jpg
17
Skeletal features heterodont dentition

• Heterodont dentition Mammals possess
  differentiated teeth (teeth that have different
  forms), which carry out different tasks
  incisors, canines premolars and molars.
• Most mammals possess two sets of teeth.
• The first set (milk teeth) has incisors, canines
  and premolars only.

18
Skeletal features heterodont dentition

• The adult dentition consists of the second set of
  the original teeth plus a set of molars.
• Mammals are the only animals that chew their food
  and the teeth are essential to this process,
  which initiates the digestive process beginning
  the mechanical breakdown of the food and
  introducing the first digestive enzymes into the
  food bolus.

19
Skeletal features single jaw bone

• In the original synapsid condition the jaw was
  made up of an anterior tooth-bearing dentary with
  a series of bones (the post-dentary bones)
  forming the posterior half.
• In this condition the articular bone of the lower
  jaw articulated with the quadrate bone of the
  skull.

20
Skeletal features single jaw bone

• In later synapsids the cynodonts a process of the
  dentary grew back and eventually made contact
  with the squamosal bone of the skull. earliest
  mammals.
• This contact eventually formed a new jaw joint
  the dentary-squamosal joint.

21
Skeletal features single jaw bone

• In the earliest mammals there were two jaw
  joints, but the original joint was eventually
  lost, and the jaw came to consist of a single
  bone the dentary and the post-dentary bones came
  to form part of the middle ear.

22
Evolution of dentary-squamosal joint http//beta.r
evealedsingularity.net/content/articles/mammal_ear
/images/jaw_artic.png
23
Skeletal features three ear bones

• In modern mammals there are three ear bones the
  incus, malleus and stapes that transmit
  vibrations from the tympanum to the oval window
  of the cochlea.
• These are derived from the post-dentary bones of
  the synapsid jaw. The use of these bones in
  hearing is not as strange as it seems at first
  because Allin (1975) suggested that these three
  bones always performed this function in synapsids.

24
Endothermy

• Along with the birds mammals are the only groups
  of endothermic animals.
• Endothermy allows mammals to occupy some very
  harsh environments, high mountains, the arctic,
  oceans that other amniotes vertebrates do not,
  but it requires the animals to expend a lot of
  energy to maintain an elevated body temperature.

25
Endothermy

• Fur plays a major role in insulation (and birds
  are similarly insulated with feathers), but it
  water it is a less effective insulator and there
  mammals have turned to blubber as an alternative.

26
Brown fat

• Mammals also possess a specialized type of
  adipose tissue brown fat that is specially
  adapted to generate heat.
• Brown fat breaks down lipids and glucose to
  produce heat and can generate as much as 10X as
  much heat as an equivalent mass of muscle.
• Brown fat is most abundant in newborn mammals
  (that lack fur) and in hibernating mammals that
  use it to rewarm the body quickly at the end of
  hibernation.

27
Cardiovascular system

• Because of their high metabolic rates, mammals
  must be able to deliver oxygen to the tissues as
  efficiently as possible.
• As in birds, a four chambered heart has evolved.
  This ensures that the oxygenated and deoxygenated
  blood are kept completely separate and maximizes
  oxygen delivery to the tissues.
• Again as in birds, the pulmonary and systemic
  circuits are two separate loops.

28
Muscular diaphragm

• Mammals have large, lobed lungs and these have a
  sponge-like appearance because of the branching
  bronchioles, which end in in blind-chambers
  called alveoli.
• Mammalian lungs are tidal (unlike bird lungs) and
  so less efficient, but are more efficient than
  reptilian lungs because they possess a diaphragm.
  
• The expansion of the rib cage which is sealed at
  the bottom by the diaphragm creates a partial
  vacuum that draws air into the lungs.

29
Sensory systems

• Mammals have exceptionally large brains and, as a
  group, most depend more heavily on olfaction and
  hearing rather than vision.
• The dependence on olfaction and hearing is a
  consequence of the fact that for much of their
  evolutionary history mammals were largely
  nocturnal and many species remain so today.
• A notable exception to this pattern is the
  primates with their diurnal habits. They
  primarily depend on vision.

30
Vision

• For nocturnal animals visual sensitivity (being
  able to form images in low light) is more
  important than visual acuity (being able to form
  detailed images).
• Most mammals have retinas filled mainly with rod
  cells, which are very sensitive to light, but
  relatively poor at acute vision.

31
Vision

• A high quality image can be formed only in the
  all-cone fovea, and these cells also allow color
  vision.
• Most mammals have either monochromatic or
  dichromatic vision (they possess only one or two
  types of cones respectively).
• The mammals ancestors had trichromatic vision
  (fish and reptiles have trichromatic vision
  turtles have tetrachromatic) but it it was lost
  in the ancestor of modern placental mammals
  presumably because of their nocturnal habits.
  Marsupials appear to have trichromatic vision.

32
Vision

• Among placentals some primates have trichromatic
  color vision. However, it was evolved from
  dichromatic ancestors and it apparently happened
  twice independently in the primates in both the
  New World monkeys and the Old World monkeys and
  apes.
• Trichromatic vision must provide a big advantage
  for these animals, most likely it enables them to
  spot ripe fruit and identify the newest and most
  tender leaves.

33
Modern mammals

• The modern mammals are derived from the synapsid
  lineage and three lineages diverged in the
  Mesozoic.
• The three groups can be separated on the basis of
  differences in reproduction
• These are the
• Monotremes egg laying platypus, echidna.
• Marsupials young poorly developed at birth,
  reared in a pouch, kangaroo, possum, wombat,
  koala.
• Placental young well developed at birth. During
  development sustained by a placenta horse,
  whale, mouse, bat, mole.

34
20.2
35
Diversification of modern mammals

• After the Cretaceous extinction 65 mya wiped out
  the dinosaurs, mammals radiated to occupy niches
  previously occupied by the dinosaurs.
• The succeeding era the Cenozoic (65 mya to today)
  is also known as the Age of Mammals.

36
Diversification of modern mammals

• When the Cenozoic began all mammals were small
  and relatively unspecialized.
• The marsupials of the time apparently were
  omnivorous and arboreal (like modern opossums),
  whereas the placentals were mostly shrew-like
  terrestrial insectivores.

37
Continental positions

• In the early Cenozoic the continents were in
  different positions than they are today and
  several were more isolated from each other than
  they are today.
• Africa separated from South America, Antarctica
  and Australia in the Cretaceous, but South
  America, Antarctica and Australia were still
  connected to each other in the early Cenozoic.
• Asia and North America were connected and eastern
  North America and Europe also were often
  connected in the early Cenozoic.

38
Continental Positions

• Obviously since the early Cenozoic continental
  position have changed.
• India collided with Asia, Africa with southern
  Europe and South America and North America have
  been linked by the Isthmus of Panama. In each
  case, the joining of land masses allowed faunas
  that had evolved in isolation to mingle.
• Mammalian diversity was thus shaped by a
  combination of diversification in isolation
  followed by later merging of faunas.

39
Continental Positions

• Major diversification of the mammals occurred at
  the beginning of the Cenozoic.
• Because early bursts of diversification that gave
  rise to multiple modern groups occurred on
  different isolated continental land masses the
  higher level classification of modern mammals
  reflects the influence of the early Cenozoic
  distribution of land masses.

40
Biogeography of marsupials

• Marsupials evolved when South America, Australia
  and Antarctica were still connected.
• When these continents separated, those on
  Antarctica were wiped out eventually by the cold
  climate as the continent drifted south. However,
  the marsupials on Australia and South America
  diversified.
• Australia remained isolated and marsupials
  diversified there in the absence of placental
  mammals. South America eventually joined to
  North America and placental and marsupial mammals
  came into contact there.

41
Biogeography of placental mammals

• Two major lineages of placental mammals the
  Afrotheria and Laurasiatheria originated on
  separate land masses in the early Cenozoic.
• The Afrotheria originated in Africa the
  Laurasiatheria in Laurasia (North America, Asia,
  Europe).

42
Cladistic Classification of the Mammalia after
Lecointre and Le Guyader (2006)
Monotremata
Marsupialia
Mammalia
Xenarthra
Theria
Tubulidentata
Afrosoricida
Macroscelidea
Afrotheria
Hyracoidea
Eutheria
Proboscidea
Sirenia
Dermoptera
Scandentia
Primates
Lagomorpha
Glires
Rodentia
Laurasiatheria
43
Afrotheria

• Members are
• Tubulidentata aardvark
• Afrosoricida otter shrews, tenrecs, golden moles
• Macroscelidea elephant shrews
• Hyracoidea hyraxes
• Proboscidea elephants
• Sirenia dugongs and manatees

44
Eulipotyphyles
Chiroptera
Laurasiatheria
Perissodacytla
Carnivora
Pholidota
Tylopoda
Suina
Cetartiodactyla
Ruminantia
Hippopotamidae
Cetacea
45
Laurasiatheria

• Members are
• Eulipotyphles shrews, moles, hedgehogs
• Chiroptera bats
• Perissodactyla Rhinos, horses, tapirs
• Carnivora cats, dogs, seals, bears, weasels
• Cetartiodactyla camels, pigs, deer, antelope,
  hippos, whales

46
Biogeography of placental mammals

• Obviously many members of both the Afrotheria and
  Lausasiatheria have dispersed widely across the
  globe since their origin.
• For example, elephants and mammoths spread
  throughout Europe, Asia and North America after
  Africa joined Europe.

47
Biogeography of placental mammals

• In other cases, groups that had diversified on
  their continent of origin were outcompeted when
  other groups arrived.
• For example hyraxes, which today exist only as
  fairly small rodent-like animals occupied
  ecological roles similar to those of pigs and
  antelopes before Africa joined Eurasia.
• Similarly, before South America joined North
  America the large carnivores were the now extinct
  borhyaenoid marsupials. Both groups were
  outcompeted by competitors from the north.

48
Borhyaena http//scienceblogs.com/tetrapodzoology
/Borhyaena20from20Argot202003.jpg
49
Rock Hyrax http//www.marietta.edu/biol/biomes/im
ages/desert/rock_hyrax_7042.jpg
50
Classification of Modern mammals

• There are only about 4800 living species of
  mammals so the group is not very species diverse,
  but it does include the largest living
  terrestrial (elephants) and aquatic animals
  (whales) and there is a great deal of
  morphological diversity.
• The mammals can be divided into three major
  lineages on the basis of differences in
  reproduction
• Monotremes
• Marsupials
• Placental mammals

51
20.2
52
Classification of modern mammals

• The marsupial and placental mammals are united
  into a group the Theria because they share a
  multiple traits that monotremes lack.
• Give birth to live young
• Nipples
• Cochlea with at least 2.5 turns
• External ear
• Lack of an interclavicle bone

53
Cladistic Classification of the Mammalia after
Lecointre and Le Guyader (2006)
Monotremata
Marsupialia
Mammalia
Xenarthra
Theria
Tubulidentata
Afrosoricida
Macroscelidea
Afrotheria
Hyracoidea
Eutheria
Proboscidea
Sirenia
Dermoptera
Scandentia
Primates
Lagomorpha
Glires
Rodentia
Laurasiatheria
54
Monotremes

• The monotremes are a small order of four species
  the duck-billed platypus and three species of
  spiny anteater or echidna found in Australia and
  New Guinea. They diverged from the lineage
  leading to the other mammals in the Jurassic
  period about 180 mya.
• Monotremes have several reptilian traits
• Monotreme means single hole in Greek and refers
  to the fact that the anus, urinary tract and
  reproductive tract all empty into a single
  opening the cloaca, as is the case in lizards and
  birds.

55
Monotremes

• In addition, the monotremes lay eggs with a tough
  leathery shell and possess an interclavicle bone,
  one found in reptiles, but not in other mammals.
• However, they clearly are mammals possessing a
  single dentary, three ear bones, hair, and milk
  although they lack nipples and the milk seeps
  from pores over a relatively wide area.

56
Platypus

• When specimens of the platypus first arrived in
  Europe they were thought to be a hoax with their
  strange combination of fur and a duck-like bill.
• The platypus bill is a highly sensitive organ
  that detects faint electrical fields.
• When hunting underwater the platypus sweeps the
  bill from side to side and the input is processed
  in the brain, a very large proportion of which is
  devoted to analyzing information from the bill.
  The electrical input enables the platypus to zero
  in on buried prey in the sediment.

57
Platypus http//www.itsnature.org/wp-content/galle
ry/platypus-and-echidna/platypus.jpeg
58
Echidnas

• Echidnas are terrestrial, covered in spines and
  eat ants and termites. They have a tubular bill.
• A fossil platypus, Obduradon, is known that is
  older than the most recent common ancestor of
  echidnas and platypuses, which means echidnas
  evolved from a platypus ancestor.

59
Echidna
60
Marsupials

• There are seven orders of marsupials with about
  275 species that include such animals as possums,
  kangaroos, wombats, koalas and Tasmanian devils.
• All marsupials have an abdominal pouch in which
  the young are raised having been born very
  underdeveloped, moving to the pouch and latching
  onto a nipple.

61
20.18
62
Marsupials

• The greatest diversity of marsupials occurs in
  Australia where the largest grazers and
  carnivores occur, but a wide variety of opossums
  occur in Central and South America.
• The living marsupials are split into two groups
  the Ameridelphia of the New World and the
  Australidephia of (mainly) Australia.

63
Ameridelphids

• There are two orders of Ameridelphids.
• Didelphimorphia About 77 species including the
  North American Opossum. The South American
  opossums are small to medium sized, omnivorous
  and mainly arboreal. Includes the otter-like
  Yapok, which catches fish.
• Paucituberculata Five species of rat opossums.
  This was a much more diverse group in the past
  and included the carnivorous, doglike Borhyaenoids

64
Yapok http//www.bbc.co.uk/nature/wildfacts/factfi
les/picpops/images/yapok02.jpg
65
Rat opossum http//www.mammalogy.org/mil_images/im
ages/mid/625.jpg
66
Australidelphia

• These all occur in Australia with the exception
  of one species that occurs in South America, the
  mouselike monito-del-monte.
• The monito-del-monte is the sole living member of
  the Microbiotheriidae, a family that was believed
  to have been extinct for more than 20 million
  years. It occurs in montane forests in Chile and
  Argentina.

67
Monito-del-monte http//www.smh.com.au/ffximage/20
08/03/27/470_marsupial,0.jpg
68
Australidelphia

• The monito-del-monte is considered to be a relict
  member of the ancestral stock of marsupials that
  migrated to Australia in the early Cenozoic.

69
Australidelphia

• The other orders of the Australidelphia are the
• Dasyuromorphia Tasmanian devil, numbat,
  marsupial mice. Three families, 60 species.
• Notoryctemorphia marsupial mole. 1 species.
• Peramelina bandicoots and bilbies. Two families,
  21 species.
• Diprotodontia possums, flying phalangers,
  koalas, wombat, kangaroos, wallabies, honey
  possum. Nine families, 110 species.

70
Dasyuromorphia

• The dasyurids are carnivorous. The marsupial
  mice (more shrew-like than mouse-like) are
  insectivorous.
• The Tasmanian devil is larger (8-12kg), doglike
  and mainly a scavenger. It is found only on
  Tasmania having become extinct on mainland
  Australia after the introduction of dingoes.
  They have powerful jaws and teeth and consume all
  parts of the carcass, bones and hide.
• In recent years numbers have declined as result
  of Devil facial tumor disease. It is a
  transmissable cancer that is spread through bites

71
Marsupial mouse http//narooma.yourguide.com.au/ m
ultimedia/images/full/178450.jpg
Tasmanian devil http//yadogg.com/wp-content/uploa
ds/2007/08/tasmanian-devil.jpg
72
Thylacine

• The Tasmanian wolf (thylacine) is extinct. It
  was a large wolf-like marsupial with a
  distinctive striped back and a spectacularly wide
  gape.

73
Thylacine http//www.thedudeclub.com/wp-content/up
loads/2008/05/thylacine.jpg
http//www.oddee.com/_media/imgs/articles/a98_Thyl
acine.jpg
74
Notoryctemorphia

• Includes only one species the marsupial mole.
• The marsupial mole is very similar in appearance
  to the true moles (Eulipotyphles) and the golden
  moles (Afrosoricida). Marsupial moles have
  spades modified out of two claws and like the
  other moles dig tunnels and feed on worms and
  insects.
• All three groups are blind, have no visible ears
  and short or absent tails and are a great example
  of convergent evolution.

75
Marsupial mole
http//farm3.static.flickr.com/2315/ 1518610598_3e
fd7ceed8.jpg?v0
http//www.nma.gov.au/shared/libraries/images/ tem
porary_exhibitions/extremes/extremes_large/austral
ia/ marsupial_mole_tanami_desert_australia/files/6
385/ nma.img-___TE02396-000-vi-vs1.jpg
76
Peramelina

• This group consists of the bandicoots and
  bilbies. Some of them have long ears, which makes
  them look a bit Iike rabbits but they are
  insectivores.
• Peramelids have the 2nd and 3rd toes of the hind
  foot reduced in size and enclosed in a layer of
  skin to form what looks like a single toe. This
  syndactylous toe is used for grooming. It is
  also found in the diprotodontians.

77
Bandicoot http//www.chocolateginger.com/bandicoot
.jpg
78
Diprotodontia

• This is the largest group of marsupials. They
  are called diprotodontians because all of them
  possess lower incisors that have been modified
  into forward projecting, somewhat rodent-like
  teeth.

79
Diprotodontia

• There are three major groupings within the
  diprotodontians
• Six families of smaller arboreal species
  including possums, cuscuses and several gliding
  phalangers including the sugar glider.
• Vombatiformes which includes the terrestrial
  wombats and arboreal koalas.
• Macropodoids which includes the small omnivorous
  rat kangaroos and the bigger, herbivorous true
  kangaroos and wallabies.

80
http//www.convictcreations.com/ animals/images/su
gargliger.jpg
Sugar gliderhttp//www.cartage.org.lb/en/themes/sc
iences/zoology/ClassMammalia/ Mammals/OrderDiproto
dontia/SugarGlider/sugarglider.jpg
81
Brush-tailed phalanger http//www.naturephoto-cz.c
om/photos/ others/brush-tailed-phalanger-62285.jpg
Spotted Cuscus http//members.optusnet.com.au/7Ea
lreadman/cuscus120hjb.jpg
82
Koalas http//www.southernmamas.com/wp-content/up
loads/2008/01/koala_baby.jpg
83
Southern hairy-nose wombat https//secure7.ozhosti
ng.com/cws/ graphics/popups/wildlife_ mammals_Sout
hern_hairy_nose _wombat2.jpg
Wombat http//www.quantum-conservation.org/EEP/WO
MBAT.jpg
84
Rock Wallaby
85
Eutherian mammals

• The Eutherian or placental mammals support their
  developing young using a chorioallantoic
  placenta which brings the blood supplies of
  mother and offspring into close contact so that
  food and gases can be effectively exchanged.

86
Cladistic Classification of the Mammalia after
Lecointre and Le Guyader (2006)
Monotremata
Marsupialia
Mammalia
Xenarthra
Theria
Tubulidentata
Afrosoricida
Macroscelidea
Afrotheria
Hyracoidea
Eutheria
Proboscidea
Sirenia
Dermoptera
Scandentia
Primates
Lagomorpha
Glires
Rodentia
Laurasiatheria
87
Eulipotyphyles
Chiroptera
Laurasiatheria
Perissodacytla
Carnivora
Pholidota
Tylopoda
Suina
Cetartiodactyla
Ruminantia
Hippopotamidae
Cetacea
88
Xenarthra

• Thirty species of armadillos, sloths and
  anteaters. They are widespread in South and
  central America and one species the nine-banded
  armadillo occurs in the southern United States.
• They are either toothless (anteaters) or have
  simple peg-like teeth. All have strong claws
  that they use for digging, ripping open termite
  mounds or to hang suspended in trees (sloths)

89
Pink fairy armadillo http//gallery.nen.gov.uk/ ga
llery_images/0709/0000/0267/ pink_fairy_armadillo_
mid.jpg
Giant Anteater http//www.junglewalk.com/ animal-p
ictures/622/ Giant-anteater-4059.jpg
90
Afrotheria

• The group includes a set of species that
  originated in Africa some of which later
  dispersed more widely.
• Members are
• Tubulidentata aardvark
• Afrosoricida otter shrews, tenrecs, golden moles
• Macroscelidea elephant shrews
• Hyracoidea hyraxes
• Proboscidea elephants
• Sirenia dugongs and manatees

91
Tubulidentata

• The Tubulidentata has only one species the
  aardvark, which occurs in Africa.
• It is nocturnal, pig-size, and feeds on termites
  and ants. It rips its way into termite mounds
  using its powerful claws.
• Its teeth are unusual (hence the name
  Tubulidentata). They lack enamel and instead of
  a single pulp cavity, each tooth has several
  upright parallel tubes of vasodentin (a modified
  dentin) each of which has its own pulp canal.

92
Aardvark http//animals.nationalgeographic.com/st
aticfiles/NGS/ Shared/StaticFiles/animals/images/p
rimary/aardvark.jpg
93
Afrosoricida

• Historically the members of the Afrosoricida were
  part of a polyphyletic group called the
  Insectivora.
• This was a hodge-podge of small mammals that ate
  insects and as well as the Afrosoricids included
  among others the elephant shrews, tree shrews,
  and true shrews all of which are now included in
  different groups.

94
Afrosoricida

• Otter shrews, tenrecs, golden moles.
• All originated in Africa and all are small
  animals with dense fur, small eyes and short
  powerful legs.
• Tenrecs occur only on Madagascar and they have
  spines scattered through the fur or just spines.
• Otter shrews look like small otters with
  elongated bodies. They have a valve of tissue
  that seals off the nostrils when diving.
• Golden moles resemble marsupial moles and talpid
  moles and the front paws have two strong claws
  used for digging.

95
Giant Otter shrew http//cas.bellarmine.edu/tietje
n/RootWeb/Insectivora.jpg
96
Streaked tenrec http//media-2.web.britannica.com/
eb-media/75/22175-004-92ADC9E4.jpg
Hedgehog tenrec http//animaldiversity.ummz.umich.
edu/ site/resources/mzm2/46.mr2.jpg/medium.jpg
97
Cape Golden mole http//www.biodiversityexplorer.o
rg/mammals/afrosoricida/images/eos03241_663x498.jp
g
98
Macroscelidea

• Elephant shrews or sengis are found only in
  Africa and there are 16 species. They eat
  invertebrates fruits and seeds.
• They are small weighing from 2 ounces to a pound.
  They have long legs, which make them swift
  runners and have long, mobile elephant-like
  noses. In their home range they maintain a
  network of paths along which they run quickly to
  escape predators.

99
Black and rufous Elephant shrews http//www.peabo
dy.yale.edu/exhibits/treeoflife/images /black_and_
rufous_elephant_shrews.jpg
100
Hyracoidea

• Hyraxes are small, tailless and stocky and weigh
  2.5-3.5 kg. They look a bit like groundhogs.
• Found in Africa and the Middle East, hyraxes are
  surprisingly good climbers and some are arboreal.
  Others are found on rock outcroppings.
• They have elastic pads on their feet, which they
  moisten with sweat to help them grip when
  climbing.
• Like rodents, hyraxes have continuously growing
  incisors and lack canines. There is gap between
  incisors and premolars (called a diastema).

101
Rock Hyrax http//www.ucmp.berkeley.edu/mammal/me
saxonia/hyrax.jpg
102
Proboscidea

• Elephants. The largest terrestrial mammals they
  weigh up to 6 tons.
• There are two living species the African and
  Asian elephants, although African forest and
  savannah elephants are genetically distinct and
  there are at least 4 subspecies of Asian
  elephant.
• They lack lower canines and the third upper
  incisors have been modified into tusks and the
  nose and upper lip into the characteristic trunk.

103
Proboscidea

• Elephants are dominant herbivores and occur in a
  wide variety of habitats from savannah to
  mountain forest (up to 5,000 m).
• They live in matriarchal family groups and
  maintain close family bonds throughout their
  lives.
• Elephants range widely in search of food. They
  require 100-200kg of vegetation daily and can be
  very destructive of vegetation and frequently
  come into conflict with humans when they raid
  crops.

104
African Elephant http//myanimalblog.files.wordpre
ss.com/ 2008/02/elephant.jpg
Asian Elephant http//www.naturephoto-cz.com/ph
otos/sevcik/asian-elephant--elephas-maximus-1.jpg
105
Sirenia

• The sirenians consist of five species of dugongs
  and manatees, which are large aquatic grazing
  mammals that typically occur in large family
  groups.
• They have no hind limbs and the forelimbs have
  been modified into swimming paddles. They are
  slow-moving and dont dive actively and sink by
  regulating the amount of air in their lungs.

106
Sirenia

• Manatees and dugongs differ in the shape of their
  tails (its bifurcated in dugongs).
• All living species are found in rivers, and
  coastal waters in warm seas and are endangered as
  a result of habitat destruction, pollution and
  conflict with humans. One species, Stellers sea
  cow, was hunted into extinction in 1768, only 27
  years after it was discovered.

107
Dugong http//www.unep.org/dewa/images/ dugong-cov
erpic-for-web.jpg
Manatee http//www.goddardscuba.com/ Schedule/2008
/manatee.jpg
108
Dermoptera

• There are two species of colugos (or flying
  lemurs) one found in the Philippines and the
  other in Java and Borneo.
• They have an extensive gliding membrane that
  stretches between the limbs and from the hind
  limbs to the tail.
• They can glide up to 150m at a time and feed on
  fruits, leaves and flowers.
• http//www.eurekalert.org/ images/kidsnews/janecka
  3LR.jpg
• Colugo http//www.americazoo.com/goto/index/mammal
  s/dermoptera.htm

109
Scandentia

• Tree Shrews (19 species) are small arboreal
  mammals that are quite squirrel like in
  appearance.
• They are diurnal animals that live in the trees
  and underbrush in forests in southeast Asia.
• They have primate-like brain and skull anatomy as
  well as almost opposable toes. However, the
  dentition is insectivorous.
• Various taxonomists have over the years grouped
  the tree shrews with insectivores, rodents,
  lagomorphs, primates and even marsupials. The
  current placement as sister group to the primates
  is based on gene sequence data.

110
Tree shrew http//www.ryanphotographic.com/images
/JPEGS/Tree20shrew.jpg
111
Primates

• Tarsiers, lorises, bush babies, lemurs, New World
  and Old World monkeys, gibbons, apes, humans.
• Primates have opposable thumbs and opposable big
  toes, which allows both hands and feet to grip
  branches.
• Orbits are forward facing for binocular vision.
  The brain is well developed in many groups and
  they are often highly social.

112
Lorisiformes
Strepsirrhini
Lemuriformes
Primates
Tarsiformes
Platyrrhini
Cercopithecoidea
Hylobatoidae
Hominoidea
Pongidae
Hominoidae
Gorillinae
Hominidae
Homini
Homininae
Panini
Classification of the Primates after Lecointre
and Le Goyader (2006)
113
Lorisiformes

• The lorises and lemurs are members of the
  strepsirrhini and they share a characteristic
  dental comb of four incisors and two
  forward-projecting canines . This is used to
  strip vegetable material (e.g. tree gum) when
  feeding and in grooming.
• Lorisiformes (10 species of lorises and bush
  babies) are small, large-eyed (200-300 g)
  nocturnal, arboreal primates with round heads.
• They occur in Africa, India and southeast Asia
  and are omnivorous eating insects, fruits and
  tree gum.

114
Lorisiformes

• Lorises (including the potto) are chameleon-like
  and slow moving. They cant jump and depend on
  camouflage and immobility for protection.
• The six species of bush baby (or galago) are much
  more agile and active and run and jump to hunt
  and to escape predators.

115
Slow Loris http//www.sfgate.com/n/pictures/2006/0
6/14/loris.jpg
Potto http//www.dumondconservancy. org/dc2005/ima
ges/web/primate 20pics/Prosimians/Loridae/ Potto
201.jpg
Bush baby http//www.hlasek.com/foto/otolemur_cras
sicaudatus_ db9035.jpg
116
Lemuriformes

• There are 22 species of lemur and they occur only
  on Madagascar where they evolved in isolation
  from competition with monkeys.
• They range is size from the mouse-lemurs (5
  inches long excluding the tail and 55 g) to the
  indri (up to 70cm and 10kg). They include the
  familiar ring-tailed lemur and the bizarre
  aye-aye.
• Lemurs are arboreal, but do not brachiate.
  Instead they jump vertically from branch to
  branch.

117
Mouse lemur http//animals.nationalgeographic.com/
staticfiles/NGS/ Shared/StaticFiles/animals/images
/primary/mouse-lemur.jpg
Indri http//www.bushhouse-madagascar.com/ images
/indri_indri_madagascar01.jpg
Ring-tailed Lemur http//www.erikvp.com/Images09/r
ing-tailed-lemur.jpg
118
Lemuriformes aye-aye

• The aye-aye is a solitary nocturnal species that
  eats fruit and insect larvae, which it digs out
  of wood using powerful forward projecting
  incisors.
• It has large ears, which it uses to detect insect
  larvae and a greatly elongated, very thin, third
  finger, which it uses to winkle the larvae out of
  their holes.

119
Aye-aye http//animals.nationalgeographic.com/ st
aticfiles/NGS/Shared/StaticFiles/animals/ images/p
rimary/ayeaye.jpg
Aye-aye hand http//alphabeticaprime.files.wordpre
ss.com/2008/02/aye-aye_hand.jpg
120
Lemuriformes

• All lemurs are threatened by habitat destruction
  as Madagascars human population has boomed and
  large areas of natural habitat have been
  converted into farmland or cut for lumber.
• Fourteen species of lemur have become extinct
  since humans arrived on Madagascar about 2000
  years ago including some that were as big as
  orang-utans.

121
Tarsiiformes

• Three species of tarsier and all are small and
  arboreal with greatly enlarged orbits.
• They have long hindlimbs and are excellent
  jumpers.
• They are nocturnal and fed on insects and small
  vertebrates.
• Found on islands in southeast Asia.

Tarsier http//blog.makezine.com/_wp- content_upl
oads_2007_08_tarsier.jpg
122
Platyrrhini

• The Platyrrhini are 51 species of New World
  monkeys and include two main groups the
  callithricids marmosets and tamarins and the
  cebids capuchins, squirrel monkeys and howler
  monkeys.
• They live in tropical rain forests and other
  forests and possess a prehensile tail which they
  can use to grip branches when climbing.

123
Platyrrhini

• Marmosets and tamarins are small 150-700 g)
  colorful monkeys that often have mustaches or
  manes of hair. Their nails have been modified
  into claws.
• They live in monogamous family groups.

Tufted eared marmoset http//cache.virtualtourist.
com/ 3862569-Tufted_ear_marmoset- Estado_da_Bahia.
jpg
124
Platyrrhini

• The cebids eat fruits, leaves, seeds, insects and
  small vertebrates and social organization ranges
  from monogamous pairs to large polygamous groups.
  One species, the northern night monkey, is
  nocturnal

Red Howler monkey
Spider monkey http//www.aguilaharpia.org/photos3/
Panama-Spider-Monkey-3.jpg
125
Cercopithecoidea

• The Old World monkeys includes 82 Afro-Asiatic
  species that include two main groups the large
  bodied, mostly terrestrial baboons and macaques
  (cercopithinae) and the smaller, more delicately
  built vervets, colobuses, and langurs
  (colobinae).
• Most species eat fruit and leaves, but baboons
  frequently hunt hares and young gazelles. All
  Old World monkeys possess a tail, but it is not
  prehensile.

126
Black and white colobus http//www.game-reserve.co
m/images/wildlife /primates_other/guereza_colobus_
monkey_02.jpg
Baboons http//www.animalwebguide.com/Baboon-2.jpg
127
Hylobatoidae

• These are the nine species of gibbons and
  siamangs, which are slender, tailess apes with
  very long arms and a highly flexible wrist, which
  allows them to brachiate. They move awkwardly on
  the ground.
• They live in family groups in the tropical
  forests of southeast Asia and feed almost
  entirely on fruit.

Hoolock Gibbon http//www.pittsburghzoo.org/uploa
d/Image/hoolock-gibbon.jpg
128
The Great Apes

• The five species of great apes are the
  orang-utan, gorilla, chimpanzee, bonobo and
  human.
• All are large with a highly folded cerebral
  cortex in the brain and all lack tails.

129
Pongidae

• The orang utan is the sole member of the Pongidae
  and they inhabit the tropical rain forest of
  southeast Asia.
• Orangs are solitary the only great ape that spend
  almost all of its time in the trees. They are
  excellent brachiators.
• The diet consists largely of fruit and leaves
  occasionally supplement with insects, eggs and
  small vertebrates.
• They are greatly threatened by loss of rainforest
  habitat in Borneo and Sumatra.

130
Orang Utan http//naturescrusaders.files.wordpress
.com/2009/04/orangutan-male.jpg
131
Gorillinae

• Gorillas are the largest living primate and live
  in small family groups led by a single dominant
  male. They are terrestrial during the day but
  sleep in trees at night.
• They are vegetarians and occur in the lowland
  forests of west Africa and mountain forests in
  Rwanda and eastern Congo.
• They are threatened by poaching and deforestation.

132
Panini

• Two species the chimpanzee and bonobo.
• They live in bands of 10-30 individuals. Most of
  the diet is vegetarian, but chimps will hunt and
  kill baby antelopes, pigs and small monkeys.
• Occur in central and western Africa.

133
http//phineasgage.files.wordpress. com/2007/06/07
0617chimp.jpg
http//www.awf.org/files/3972_image2_western_goril
la_MWatson.jpg
134
Homini

• Humans largely hairless great ape.
• Posesses advanced reasoning and communication
  capabilities and a high degree of technological
  sophistication.
• Highly social. Widespread.

135
Glires Lagomorpha

• The lagomorphs consist of about 80 species of
  rabbits, hares and pikas. Strictly vegetarian
  they have a well developed cecum to facilitate
  digestion of vegetation.
• Rabbits and hares have long legs and are fast
  runners. They also have long ears (especially in
  species from hot regions).
• Pikas are primarily found in mountainous, alpine
  terrain.
• They were once grouped with the rodents as they
  also have prominent incisors used for gnawing.
  However, they have two pairs of incisors in the
  front of the mouth (the 2nd pair are vestigial
  and located behind the first).

136
Pika http//media-2.web.britannica.com/eb-media/16
/3516-004-67E3395A.jpg
137
Glires Rodentia

• Rodentia Rodents. The largest group of mammals
  with more than 2000 distributed worldwide.
• Includes more than 1,300 species of rats and mice
  as well as squirrels, mole rats, woodchucks,
  beavers, gerbils, lemmings, capybaras, and
  agoutis.

138
Rodents

• The key to their success is their chisel like
  upper and lower incisors that grow continuously.
  
• The front of the tooth has a thick layer of
  enamel but the rear has a layer of dentine that
  is much softer.
• The movement of the upper and lower incisors
  against each other wears down the dentine and
  leaves a very sharp chiseled edge that enables
  the rodents to open even the hardest seeds. To
  assist in their chewing the rodents also have
  highly enlarged masseter muscles.

139
Beaver teeth http//www.arkive.org/media/ 20/20646
7D2-694F-4269-BFBC- 9925111529EE/Presentation. Lar
ge/photo.jpg
http//www.usefilm.com/images/ 4/8/6/8/4868/124626
9-medium.jpg
140
Rodents

• Various species of rats and mice have spread
  across the globe as commensals with humans. They
  are enormous pests of stored foods especially
  grains and almost certainly there are more
  rodents on earth than all other mammals combined.
• They also are major vectors of disease such as
  typhus and bubonic plague. In the past 1,000
  years rodent spread diseases have probably been
  responsible for more humans deaths than all wars
  combined have caused.

141
Cladistic Classification of the Mammalia after
Lecointre and Le Guyader (2006)
Monotremata
Marsupialia
Mammalia
Xenarthra
Theria
Tubulidentata
Afrosoricida
Macroscelidea
Afrotheria
Hyracoidea
Eutheria
Proboscidea
Sirenia
Dermoptera
Scandentia
Primates
Lagomorpha
Glires
Rodentia
Laurasiatheria
142
Eulipotyphyles
Chiroptera
Laurasiatheria
Perissodacytla
Carnivora
Pholidota
Tylopoda
Suina
Cetartiodactyla
Ruminantia
Hippopotamidae
Cetacea
143
Eulipotyphyles (insectivores)

• This group of almost 300 species includes much of
  what was historically included in the
  insectivores, desmens, shrews, moles,
  hedgehogs, and solenodons.
• They are small to very small (the pygmy
  white-toothed shrew at 2g is the worlds smallest
  mammal).
• Highly active with very high energy needs, mostly
  terrestrial insect eaters and occur worldwide.
• Generally the senses of smell and hearing are
  most important and they tend to be solitary and
  aggressive.
• Both moles and hedgehogs have ecological
  equivalents in other groups, the result of
  convergent evolution.

144
20.28
145
Chiroptera

• Bats. Nocturnal flying mammals with forelimbs
  modified into wings. The flight membrane is
  stretched between long fingers (the metacarpals
  are enormously elongated).
• Many species use echolocation. About 925 species,
  second only in size to Rodentia.
• There are two major groups the large
  megachiroptera (the fruit bats) which have
  long-muzzled fox-like faces and mainly eat fruit
  and the microchiroptera which have flattened
  faces, small eyes and large ears.

146
http//fireflyforest.net/images/firefly/2007/ Febr
uary/Lesser-Long-nosed-Bat-1.jpg
Epauletted fruit bat http//www.taos-telecommunity
.org/epow/ EPOW-Archive/archive_2008/ EPOW-080317_
files/ P116066320wahlbergs20epauletted20fruit2
0bat_s.jpg
147
Perissodactyla

• Odd-toed ungulates. Horses, zebras, asses,
  tapirs, rhinoceroses. 18 species. They have a
  long muzzle with strong prehensile lips.
• The main supporting axis of the hind limbs passes
  through the third toe.
• Horses donkeys and zebras have a single toe,
  rhinos and tapirs have three toes on the hind
  feet, but tapirs have 4 on the forefeet (but the
  third toe is the strongest)
• All herbivorous with teeth adapted to chewing
  vegetation. The caecum in the intestines
  (analagous to the rumen in ruminants) is enlarged
  and anaerobic fermentation of cellulose by
  bacteria takes place there.

148
20.32
149
Carnivora

• Medium to large flesh-eaters. Cats, dogs,
  weasels, badgers, mongooses, racoons, bears,
  seals, sealions. 271 species.
• Teeth specialized for killing. Canines are long
  and pointed and molars have numerous slicing
  cusps for shearing meat.
• The last upper premolar and first lower molar are
  modified into carnassial teeth that work like
  scissors to cut meat away from bones.

150
http//www.cartage.org.lb/en/themes/sciences/zoolo
gy/ Animalclassification/OrderPrimates/carnassials
.jpg
151
Pholidota

• Pangolins. Seven species of scale covered
  anteaters with powerful claws. They lack teeth
  and have a tube-like snout with a very long
  tongue (up to 16 long).
• They are mainly nocturnal and are found in
  Africa, India and southeast Asia.
• To escape predators they curl into a ball so
  tightly that a man cannot unroll them.

http//www.vulkaner.no/n/africa/ somalia/pangolin.
jpg
152
Cetartiodactyla

• Traditionally, the members of this group were
  classified as two groups the Artiodactyla
  even-toed ungulates pigs, deer, cattle,
  antelopes, hippopotamuses and the Cetacea whales
  and dolphins.
• Recently, it has become clear that the cetaceans
  are embedded within the Artiodactyla and evolved
  from hoofed predators called mesonychids.
• Cetaceans are more closely related to hippos than
  hippos are to the other members of the
  Artiodactyla. As a result, the Cetartiodactyla
  has been created.

153
Traditional Articdactyls

• There are four groups in the Cetartiodactyla that
  would have been included within the previous
  Artiodactyla.
• Tylopoda Camels and vicunas. 6 species.
• Suina pigs, warthogs, peccaries. 19 species.
• Ruminantia Deer, bison, cattle, antelope. 191
  species.
• Hippopotomidae Hippos 2 species.
• Two or four toes sheathed in hoofs. Most are
  ruminants and possess multi-chambered stomachs.

154
Eulipotyphyles
Chiroptera
Laurasiatheria
Perissodacytla
Carnivora
Pholidota
Tylopoda
Suina
Cetartiodactyla
Ruminantia
Hippopotamidae
Cetacea
155
20.32
156
Cetacea

• Whales and dolphins. Aquatic diving mammals.
  Anterior limbs modified into flippers, posterior
  limbs absent, possess large rear fluke for
  propulsion, nostrils modified into blowhole on
  top of head. 78 species.

157
Cetacea

• The two basic divisions of the cetaceans are the
  toothed whales (Odontoceti) and the baleen whales
  (Mysticeti).
• Toothed whales (e.g. sperm whale, killer whale,
  dolphins) have homodont dentition. The teeth are
  used to capture prey, but not for chewing.
• Baleen whales (e.g., blue whale, humpback whale,
  sei whale) feed on smaller prey that they filter
  using their baleen, which is made of keratinized
  extensions of the epidermis. Baleen whales take
  in a mouthful of water and press their tongue
  against the baleen to squeeze out the water and
  then swallow the food trapped inside the mouth.

158
Humpback whale