2. Classifying species into taxa
• Linnaeus
u physical similarity
u Genus species, e.g. Homo sapiens
• Darwin
u similarity due to common descent
VERTEBRATES
Birds Mammals
Sparrow Flamingo Lion Squirrel
12. What makes an animal a primate?
• Features of hand & feet
u Grasping big toe
u Grasping hands
¨ Some opposable thumbs
u Sensitive finger tips
¨ Finger prints!
u Flat nails
u Generalized limb structure
13. What makes an animal a primate?
Features of the sensory organs - Vision
• Forward facing eyes
¨ Binocular vision
• Stereoscopic vision
u Information sent to both
hemispheres of brain
• Depth perception
• Color vision
• Limited olfactory senses
(except prosimians)
Pygmy marmoset
Golden monkey
16. What makes an animal a primate?
Features of life history
• K-selected
u Large maternal
investment in care
• Small litters
• Long pregnancy
• Long infancy
• Long juvenile period
• Long mother-infant bond
• Long life span
• Long reproductive period Savanna baboon
17. What makes an animal a primate?
Features of the teeth
Generalized teeth, four kinds,
many functions
Comparison:
18. • Enclosed bony eye sockets
What makes an animal a primate?
Features of the skull
• Comparison: cat skull
19. What makes an animal a primate?
Large brain relative
to body size & an
emphasis on
learning
22. But, monkeys have also adapted to wide range
of habitats
Primary tropical forest
Secondary forest
Desert
Temperate forests
23. What are these
adaptations for?
1. Arboreal Hypothesis
u Stereoscopic vision
u Grasping hands
u Nails
= adapted for life in the
trees
But squirrels do pretty
well without
thumbs…
24. galago
What are these adaptations for?
2. Visual Predation Hypothesis
u Analogy with insectivores
u Stalk and capture insects
u Depth perception
u Grasping hands
= adapted to catch fast moving prey
25. What are these adaptations good for?
3. Angiosperm Radiation hypothesis
• Adapted to eat flowering plants
• Color vision
• Fine visual & tactile
discrimination
28. Basic primate phylogeny (relationships)
Lemurs, lorisesTarsiers
ProsimiiAnthropoidea
New World
Monkeys
Old World
MonkeysApes & humans
Haplorhines
Strepsirrhines
Primates
(Hominoidea) Platyrhines
Cataryhines
29. Prosimians are the most primitive primates
(Strepsirhines)
The most different from us
• Many are nocturnal
• Many are solitary
• Some w/ claws instead of nails
• Some w/ acute sense of smell
u Rhinarium
u Scent marking
Two types:
Lorises
Lemurs
Potto (Loris)
Bush Baby (Loris)
30. Prosimians divided into two groups: Lemurs
• Only on Madagascar
• No competition from other
primates
• No large predators on island,
until humans 1500 ya
• Many different species
sifaka
dwarf lemur
avahi aye aye
31. Haplorhines: Monkeys, Apes, Tarsiers
Most of the primate adaptations
• Vision > Olfaction
• Eyes surrounded by bone
• Fused midline of lower jaw
• Diurnal
u Except Tarsiers
u Except Owl monkey
• Social
u Except Orangutan
• Larger brain
Red faced spider monkey
32. Tarsier: Prosimian & Haplorhine
• Mixture of anthropoid &
prosimian traits
• Dry nose
• Partially closed eye socket
• Nocturnal
• Only carnivorous primate
• Eat insects and small
vertebrates
33. Anthropoids: monkeys & apes
New World monkeys (Platyrrhini)
• Latin America
• Diurnal
• Arboreal
• Tropical forests
• Dental formula (I.C.P.M.)
2.1.3.3
2.1.3.3
38. Question:
Match the traits with the taxonomic groups – a
trait may belong to more than one group
1. Strepsirrhines
2. Platyrrhines
3. Catarrhine Monkeys
4. Hominoidea
a. Color vision
b. Extended life history
c. Scent marking
d. Opposable thumb
e. Dental comb
f. No tail
g. Rhinarium
40. Forms of Locomotion
• Vertical Clinging & Leaping
• Arboreal Quadrupedalism
u Use of prehensile tail in some
species
• Terrestrial Quadrupedalism
• Brachiation
• Knuckle walking
• Bipedalism
43. In Class Activity
• Skeletal features to note:
u Body position (upright (orthograde) or horizontal
(pronograde)
u Length & shape of trunk (torso – barrel or wide and
flat)
u Position of shoulder blade (scapula – side or back)
u Spine shape (C or S shaped)
u Limb length (arms vs. legs)
u Finger length (fingers, thumbs)
u Length of tail
44. Intermembral Index
• humerus + radius x 100
femur + tibia
• hindlimbs vs. forelimb
u longer in the part that does the most work
• Bipeds & vertical clinging and leaping
u hindlimb longer than forelimb
• Quadrupeds
u Approx equal lengths
• Brachiators
u forelimbs longer than hindlimbs
45. Vertical clinging and leaping - prosimians
• Vertical body
u Orthograde
• Push off branch with hindlimbs
• Turn midair and land vertically
again
• Bush babies
• Sifakas
• Lemurs
Sifaka
46. Arboreal quadrupeds – monkeys
• Arboreal - run & leap
• Walk on palms on top of branches
• Push off with hindlimbs
• Stabilize with tail (long)
• Pronograde (horizontal) posture
• Longer fingers & toes to grab branch
• Approx. equal limb length
• Prehensile tails in NWM
• No terrestrial species in NWM
Owl Monkey
Squirrel Monkey
Diana Monkey
49. Brachiation - gibbons
• Shoulder blade on the back
rather than top of torso
u Full range of arm motion
• Long, curved fingers
• Small thumbs
• Long arms
• No tail
Siamang
50. Knuckle-walking - chimps & gorillas
• Great apes too large to brachiate frequently
u Still use upper body and arms, suspend
body when they do
• Stronger wrists bones than brachiators in
order to support weight on arms
• Brachiating ancestors
u Longer arms
u Longer fingers
u No tail
u Scapula on back
Chimpanzee
52. Changes in the pelvis narrowly center our
weight
Human pelvis is a bowl
u Maintains the center of gravity
over one foot while walking
Chimp pelvis is longer and narrower
53. • S-shaped curves in
spinal column keep
trunk centered over
pelvis
• Lumbar curve
• C-shaped curve in
chimps more
Changes in the spine center our weight over
the pelvis
54. To walk efficiently, knees must be close to
center line of body
• Femur slants inward from
wide pelvis
u Centers weight for balance
• Longer leg bones
u Increased stride
chimp human
55. • Arched foot
u spring -like shock
absorbers
u Heel-toe stride
• Loss of opposable toe
• Stiff foot makes better platform
Bipedality also causes changes in the feet
56. Changes in the skull: Foramen magnum
• Hole in skull where spinal cord and brain connect
• Position indicates body posture
• Human skull is balanced on tops
63. Question
• Which of these are characteristic of humans but not other
primates? (you may choose more than 1)
a. Long fingers & short thumb
b. Large projecting canines
c. Largest brain
d. Bowl shaped pelvis
e. Long tails
f. Pronograde
64. Next Time …
• Topic: Primate Behavior
• Read articles:
u Primate Sociality and Social Systems
u Primate Cognition