Download Introduction to Primates

Limbs and locomotion
Introduction to the Primates
•Pentadactyly
•Nails
•Prehensile hands and
feet
Characteristics and Classification
Teeth and diet
•Generalized dental pattern
Senses
–Molars especially non-specialized
•Generally Omnivorous
–Not over-specialized
•Reduction in snout and associated brain areas
•Increased visual cortex in brain
–stereoscopic vision, sensitive color vision
Brain, Behavior
•Expansion and increasing complexity of
brain
•Longer gestation, infancy
•Dependence on flexible, learned behavior
The Arboreal Adaptation:
•Primate adaptations to living in the trees:
–Limbs for climbing by grasping
•Primate adaptations for visual predation:
–Stereo/color vision for preying on insects
–Grasping extremities to anchor and grab bugs
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Grades of Primate Evolution
Out-group: Tree shrews
•Insectivores, not Primates but close
relatives
•Small, squirrel-like body
•Long, projecting snout
•Claws, not nails, on digits
•Absentee mothering
•Tendency to grasp
Lemurs and Lorises
•Some nails, not claws on
all digits
•Nearly stereoscopic
vision
–Post-orbital bar
•Moist rhinarium
•Immobile face
•Mobile ears
•Seasonal breeding
•Relatively simple social
organization
Tarsiers
•Closed eye orbits
•Dry nose
•More flexible upper
lip
•Small body size
•Mobile ears
•Relatively simple
social organization
Quadrupedal Monkeys
Monkeys
•Relatively large brain
•Fixed ears
•Highly flexible face
•Complex social patterns
•Quadrupedal body and shoulder
•Tails (some prehensile in New World)
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Hominoids
•Brachiating body and shoulders
•No tails
•Relatively large body
•Relatively large brain, long infancy
•Highly complex social patterns
Brachiating
Hominoids
Primate Behavior and Ecology
Primate Behavior and Ecology
•Habitat
–The physical setting
where an animal
lives, usually
described in terms
of climate and floral
assemblage
•For primates these
are predominantly:
–Tropical Rainforest
–Woodland
–Savanna
•Niche
–The unique way of life of a plant or animal
species. How it interacts with its habitat
•Primates niche dimensions
–Arboreal versus terrestrial
•How much time spent on ground
–Diurnal versus nocturnal
–Diet
Primate Behavior and Ecology
Primate Diet
•Most primates are omnivorous, but they
tend to have preferences
–Insectivorous: prefers bugs
–Gummivorous: prefers gums and saps
–Gramnivorous: prefers seeds
–Folivorous: prefers leafs and shoots
–Frugivorous: prefers fruits and flower
–No true carnivores
• Home range
– The area exploited by an
animal or social group
– Usually given for a year-or the lifetime of the
animal.
• Core Area
– The portion of the home
range containing the
highest concentration and
most reliable supplies of
food and water
– The core area is frequently
the area that will be
defended if the animal is
territorial.
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Social Groups
Primate Behavior and Ecology
•Territory
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range actively defended against intrusion,
particularly by members of the same species.
• Solitary
– no group, just solitary adults
and females with immature
offspring
•Many nocturnal arboreal
promsimians
• Noyau
– Solitary adults who defend
home range from same-sex
individuals, but opposite sex
animals range can overlap
•Many nocturnal arboreal
prosimians
Social Groups
Social Groups
•One-male
–Characterized by a single
adult male, several adult
females, and their immature
offspring
•M ost common primate mating
structure with only one
breeding male
•Forms by male joining a group
of females or displacing a
previous male
•Females form the permanent
nucleus of the group
•Guenons, orangs, gorillas,
patas monkey
•Multimale/Multifemale
–Several adult males,
several adult females, and
their immature offspring
•Several of the males
reproduce
•There may be tension and
dominance hierarchies
•Some lemurs, macaques,
savanna baboons, spider
monkeys, chimpanzees
Social Groups
•Monogamous pair
–A mated pair and their
immature offspring
•Usually highly arboreal
species with little sexual
dimorphism
•Adults usually do not
tolerate other same-sex
adults
•Least common breeding
structure in non-human
primates
•Gibbons, titis, pottos
Primate Behavior
•Dominance
–The domination of some members of a group
by other members. A hierarchy of ranked
statuses sustained by hostile, or the threat of
hostile, behavior, which may result in greater
access to resources such as sleeping sites, food,
and mates
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Primate Behavior
•Grooming
–Cleaning of the hair or fur. Frequently used as
a bonding mechanism
•Displays
–Sequences of stereotyped behaviors that serve
to communicate emotional states. Nonhuman
primate displays are most frequently associated
with reproductive or agonistic behavior
Primate Behavior
•Mother-infant bond
–The attachment between mother and her
offspring. This is one of the strongest social
bonds among non-human primates
•Male-female bond
–Most adult males and females form temporary
attachments lasting only while the female is in
estrus (sexually receptive). Notable exceptions
include the monogamous pair species
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