Nocturnal or Madagascar
or both
P
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m
a
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s
S.E. Asia
S. America
“Old World”
Origins and Relations?
Evolution
• Primate adaptive themes: “…exploitation of arboreal
herbivory, arboreal locomotion, manual dexterity,
stereoscopic vision, and complex social behavior and
communication.” (Vaughan et al., 2000)
• Increased manual dexterity (next 2 slides) may be correlated
with increase in brain size.
• Mostly animals of the humid tropics, primates are an
ancient (Cretaceous) Order, probably evolving in N. Am.
(soon extinct) (Europe )Asia & Africa S.America
• It is useful to consider the Primates as 2 Suborders:
– The Strepsirhini (“prosimian” lemurs, bush babies, galagos, etc.).
– The Haplorhini (anthropoids: monkeys, apes, people).
– The tarsier does not fit well with the anthropoids, but it is not a
strepsirhine.
“Prosimians” (For each pair, hand is on left.)
“Anthropoid” primates (hands on left)
Taxonomic generalization (“suborders”)
• Strepsirhini (prosimians)
• Probably somewhat like
earliest primates.
• Either Madagascar, or
nocturnal, or both (all are
tropical).
• Apparently do not compete
effectively w/monkeys, etc.
• In contrast w/anthropoids:
– More smell-oriented
– Less obviously social
– Seasonal breeders
• Haplorhini (anthropoids)
– Platyrrhini (New World)
– Catarrhini (Old World)
– Tarsiars are placed in this
group largely because of
molecular evidence.
• People are worldwide;
most other species are
tropical.
• A commonly noted trend
is toward behavioral
(often social) adaptation
rather than anatomicalphysiological adaptation.
Ecological generalizations
(regardless of taxonomic position)
• Smaller primates:
– For S/V reasons, must
exploit high-energy foods.
– All eat arthropods plus
occasional small vertebrates,
which are difficult to collect
in quantity. (Think protein.)
– Therefore most have other,
reliable, sources of calories:
• Fruit (very seasonal)
• Seeds (somewhat seasonal)
• Resins & saps (less seasonal)
• Larger primates: Most are
either leaf specialists or
fruit specialists:
– “Leaf eaters”: Energyconserving second-rate
fermenters that usually
supplement calories with
fruit. (These get plenty of
protein if they make their
calories.)
– “Fruit eaters”: Plenty of
energy; must supplement
protein with selected leaves
or seeds or animal matter.
Tarsius: Anthropoid life in the dark
Reputedly has
largest eyes (per
body size) of any
animal; even
gives up eyemobility for size.
(Why is size
important?)
Other night-vision
adaptations….
• Formerly called a
prosimian, now classed
w/anthropoids, mostly on
molecular evidence.
• The Family Tarsiidae
includes 5 species in one
genus.
• H-b of T. bancanus is 8.516cm; mass is 100-150g.
• Nocturnal S.E. Asian
primates eating only
animal matter.
• Solitary/social  an
important concept
• Diagram compares
right feet of tarsier
and brown lemur.
• Note extreme
elongation of the
calcaneum and
navicular (tarsal
bones) in the
tarsier.
• The tarsier also has
a radically different
mechanism of footrotation so that it
can grasp vertical
stems with inverted
foot.
Uh, why do they call it a
tarsiar?
Family Galagonidae (4g/11sp)
• All are restricted to Africa.
• All are nocturnal.
• All have long tails, large, mobile ears, and strong
hind limbs (all are great leapers).
• All are highly vocal.
• Diets vary, but galagos eat lots of arthropods (from
which they derive some calories & all necessary
protein). Most usually supplement this diet with
fruit or with gums and resins.
• All are seasonal reproducers.
Galago sp. Lesser bush baby
• These African primates are
slightly larger than tarsiars,
and they have long tails.
• Primary habitat is woodlands.
• Mature more rapidly than
other primates (XX sexually
mature < 1 yr).
• Except for mother with
offspring, most galagos are
solitary, but community is
defined by scent marks.
• In some areas, > 1 Galago
species live sympatrically;
partitioning should be studied.
Otolemur
crassicaudatus,
greater bush baby
• Woodlands of southern Africa, including
suburbs.
• Mass 1-1.5kg (XX slightly larger).
• > 50% of calories from gums & resins
(especially in winter).
• Social structure poorly known:
– XY said to be solitary; XX said to move in
groups?
– XX territories overlap, but not much; XY
territories encompass XX territories but
don’t overlap other XY territories?
– How do you resolve the contradictions?
Family Lorisidae (lorises & potto)
• These are slow-moving nocturnal animals relying in
part on gliding motion to avoid detection by
predators.
• Unlike galagos, they do not jump.
• Wrists & ankles specialized:
– Great range of motion.
– Hands & feet are zygodactylus.
– “Special blood vessel storage channels in their hands and
feet enable lorises to contract their muscles and hold
tightly to a branch for hours, seemingly without fatigue
or pain.”
• Socially, these primates live in a world of smells.
Loris tardigradus
(slender loris)
• Range is s. 2/3 of India
plus Sri Lanka.
• Mass is 200-450g.
• Diet is mostly
arthropods.
• Solitary but social (!):
– Foraging usually solo,
sleeping often not;
– XY mark territories by
fecal sign posts;
– XX leave urine trails
w/social information.
Nycticebus
coucang, slow loris
• Deep-forest animal of S.E. Asia.
• H-b 25-35cm, mass 1.5kg.
• Diet 50% fruit w/ protein hits
from small animals.
• Social structure & ecological
relationships to other loris sps
are poorly known in wild.
Perodicticus potto, the
potto
• Nocturnal animal
of W. African
rainforest canopy.
• H-b 25-35cm;
mass 1kg.
• Basis of diet is
fruits, plus gums
and small animals
for protein hits.
• Young learn to eat
by foraging with
mother.
• Defensive
behavior….
The Lemuriform primates
• All of these are restricted to Madagascar (see next slide).
• Here are some Family sketches:
– Cheirogaleidae: 4 genera of nocturnal primates ecologically more
similar to African prosimians than to other Madagascar lemurs.
– Megaladapidae: Has only 1 living species, a leaf-fermenter, but
formerly included huge terrestrial types filling artiodactyl niches.
– Lemuridae: 4g/10s. Most species are diurnal. Often partition
habitat finely; mostly monkey-convergents.
– Indridae: 3g/5s. Large leaf-eaters, mostly diurnal. Some extinct
members were large, terrestrial browsers.
– Daubentoniidae: The aye-aye is a strange nocturnal insect-eater, a
woodpecker-convergent.
Alternative Evolution: Madagascar invaded by only 6
mammal Orders: Insectivores, carnivores, rodents, bats,
artiodactyls & primates.
Patterns of Malagasy Extinctions
Aye-aye
Daubentoniidae
• Originally classified
as a rodent, this
nocturnal primate
occupies
woodpecker niche
on Madagascar.
• Note chisel teeth,
long middle finger,
and use of the finger
in feeding.
• Like much other
Malagasy fauna,
aye-ayes are
endangered by
habitat destruction.
Brown & ringtail lemurs
(Lemuridae; 5 genera,
about 25 species)
• Eulemur fulvus:
– Mostly arboreal.
– Leaves & fruit.
– Flexible, multi-XY
groups that can fracture
into subgroups.
• Lemur catta:
– Mostly terrestrial.
– Dietary generalists.
– Group structure is
organized around XX
residents which are
entirely dominant over
transient XY.
Behavioral adaptability in the Lemuridae
Fat-tail & mouse lemurs
(Cheirogaleidae; 4 genera; 17
species)
• Cheirogaleus
medius (left):
– 200g (medium rat).
– Eat fruit + protein
hits.
– Only hibernating
primate.
• Microcebus murinus
(right):
– 30g (medium
mouse)
– Rainforest-edge
species
– Foraging (for
anything) mostly
solitary, but XX
day-nest together.
– Heavy depredation
pressures; rapid
maturity & twiceannual litters of 2-4.
Anthropoid primates: Phylogeny & general trends
•
•
•
•
•
Increased body-mass
Increased brain-mass/body-mass
Longer life
Increased manual dexterity
Specialization of eyes:
– Binocular vision (at expense of olfaction)
– Increased density of cones
– Emphasis of visual acuity over light-gathering
Notes on sociality in “higher” primates:
• Primatologists are abundant and specialized; often they use
a vocabulary of their own, naming many types of social
structures.
• Most general mammalogists agree that:
– Primate groups vary among and within species.
– Most social organizations seen in primates have also been
documented in other mammal species.
– Intraspecific variation is often correlated w/habitat.
– Territorial XY primates appear more attached to XX’s than to land.
– XX among primates are more likely (than XX among other
mammals) to leave natal groups (but remember equids?).
– Human social organization varies & is almost unique.
New World Monkeys
• Ancestor rafted
from Africa.
• Groupings:
– M&T: small, fruit
& exudate eaters.
– C&S: Highly
adaptable fruit
eaters.
– N&T: Unripe fruit,
leaves, insects.
– U&S: Seed eaters.
– H: Leaf eaters.
– S&W: Large,
brachiating fruit
eaters.
Callitrichidae (marmosets; our first anthropoid Family)
• 4 genera/26species of small monkeys confined
almost entirely to South American forests.
• Evolutionary origins controversial:
– Small size is primitive condition?
– Small size is specialization for insect & resin diet?
• Little sexual dimorphism….
• Group nucleus is one breeding pair (often
monogamous) that is often assisted by stay-at-home
older kids.
• Litter size is typically 2 (dizygotic twins; shared
placenta…); offspring receive extensive family care.
Marmosets & tamarins
(Callitrichidae)
• Golden-chested
marmoset:
– Mass < 500g; squirrel-like
in activity.
– Most calories from resins.
– Sociality &
reproduction….
• Golden lion tamarin:
– Mass c. 500-750g.
– Most calories from fruits.
– Sociality &
reproduction….
New World Monkeys: Cebidae
• 11 genera, 58 species, small to medium size.
• Vast majority South American w/ some species
extending into Central America and a few crossing
into North America (in s. Mexico).
• Evolutionary origins unclear, but emerging
consensus holds with rafting from Africa?
• All species but one are diurnal.
• Tail typically long, often prehensile.
• Major ecological differences are between fruit-eaters
and leaf-eaters.
Squirrel monkeys
(Saimiri)
• Not much larger
than marmosets
(0.7-1.2kg).
• Social and arboreal
omnivores.
• Large groups,
poorly studied:
– XX: maturity @ 2
yrs; sisterhood,
“aunting.”
– XY: Loose
dominance
hierarchy mediated
by physiological
changes.
Cebus monkeys
• Cebus has the largest
brain/body ratio of any
New World primate.
• Most diverse diet of
any New World
primate.
• One of few mammals
in which XX’s often
outlive repro. years.
• Members of this genus
are highly adaptable:
– In the wild: home range,
occasional tool-use,
social organization.
– In captivity, general
“train-ability.”
C. albiniforns (left)
C. capucinus (right)
Dusky Titi
Monkey
(Callicebus
moloch)
• Diet is mostly
leaves and green
fruit, supplemented
by ripe fruit and
insects.
• Titis are basically
monogamous,
bearing young
early in rainy
season.
• Although they do
well in zoos, these
monkeys are not
well known in the
wild.
Night Monkey (Aotus
trivirgatus)
• Sometimes called owl
monkeys, these are the
most nocturnal anthropoid
primates.
• Diet is fruit, leaves, &
insects (+ small verts).
• Basically monogamous.
• The taxonomy of this
monkey is confusing;
some authorities name up
to 9 species.
• This species is of
considerable medical
interest because owl
monkeys are immune to
malaria.
Uakaris (Cacajao calvus)
• These are poorly known
monkeys with short tails,
shaggy bodies, & naked
heads.
• Mass is 3-4kg w/XY
slightly heavier than XX.
• Habitat makes study of
uakaris almost impossible
• Multi-XX, multi-XY
groups w/XY dominance.
• Food may be primarily
seeds.
Sakis (Pithecia
sps.)
• Sakis are medium-small
monkeys (1.5-2kg).
• Diet includes fruit but is
probably dominated by
seeds and nuts (see teeth).
• Social structure is not well
known but involves
breeding pairs. (Sakis are
sexually dichromatic.)
• These are great leapers in
mature forests.
Howlers (Alouatta sps.)
• The most common monkeys
in most Neotropical
systems.
• XX mass 4-5kg; XY 6.5kg.
• Cautious, “lazy” leaf-eaters
marking territory by
vocalizations.
• Group size reflects resource
density.
• Groups are 1-XY harems
within which XX rankings
are age-inverted.
Wooly & Spider
Monkeys
• These are the largest New
World monkeys; h-b length to
60cm & mass to 12kg.
• Diet is mainly fruit,
supplemented for protein.
• Group structure is highly
flexible, varying with habitat
and season.
• Sexual dimorphism is
minimal; though males do
have dominance hierarchies,
they are loose & generally agestructured.
“Old World” Primates
Family Cercopithecidae
• The most successful primate Family (18g/81s)
• Africa; East, South, & Southeast Asia. Extending
beyond tropics in southern Africa, China, Tibet, and
Japan.
• Mass ranges from 1.5 to > 50kg.
• Most are diurnal; all are highly social.
• Ecologically divisible into 2 groups:
– Colubinae, the Old World leaf eaters
– Cercopithecinae, the Old World generalists.
African leaf-eaters (e.g.,
Colobus guereza)
• Mass XX 8kg; XY
12kg.
• Central Africa; habitat
is rainforest, gallery
forest, well-structured
secondary forest.
• The most capable
fermenters among
African primates (all
primates?).
• Multi-XY groups (815) w/dominance
hierarchies.
• Small (c. 18ha) ranges
defended against
other groups.
Asian leaf-eaters (e.g., Semnopithecus entellus)
• Hanuman langurs are
south-Asian.
• XX 12kg; XY 18kg.
• Diet 35% leaves, 25%
fruit; 40% misc.
• Social structure changes
as function of monkey/
resource density:
– Low: multi-XY groups.
– High: 1-XY harems plus
bachelor groups that take
over harems (“lion”
pattern).
Cercopithecus
[Chlorocebus] aethiops
• Found in southern African open
woodlands.
• XX 3kg; XY 4kg.
• Group size ecologically flexible
(usually 15-25) with multiple
XY and dominance hierarchies.
• XX stay in natal group; XY outmigrate.
• CIV’s:
– Each species of Cercopithecus
(sensu lato) may have its own.
– About 50% are non-symptomatic
carriers.
Baboons (Papio hamadryas)
• Baboons are large, panAfrican monkeys living in
large, intricately-structured
social groups evolved in
part for collective defense.
• Sexual dimorphism is
extreme: XX 15kg; XY to
50kg.
• Diet includes anything that
provides good nutrition.
Further baboon notes
• Group structures and subspecies/habitat differences:
– Effectiveness of group defense where needed….
– Southern African savannas: 20-50 animals; group defense in a
predator-rich environment.
– Ethiopia: Few big, safe sleeping areas (& thus groups of several
hundred baboons); sparse resources (& thus foraging groups of 12XY + XX), residual “typical” groups….
• Life within a group:
– XY hierarchy obvious & important; XX hierarchy subtle and more
important for eventual status of offspring. Until mature, (c. 4
years) XY remain subordinate to XX.
– “Godfather” relationships rare but potentially important.
– “Political” behavior, troop shake-ups, and XX behavior.
Other baboon-like monkeys
• Mandril (Mandrilus spinx): This is a large monkey
with brightly-colored face & hindquarters, poorly
known in the wild, that fills a baboon-type niche in
African rainforests. Groups are smaller than among
baboons.
• Gelada (Thercopithecus gelada): This is a big
monkey of the Amhara Plateau. Sociality looks at
first like that of baboons– but XX are socially more
important. Perhaps this reflects the fact that gelada
XX stay with their natal groups while baboon XX
out-migrate.
Macaques (Asian generalists)
• Macaques include one genus
(Macaca) & 16 sps.
• Diets, social structures, and
habits vary by habitat, but all
are adaptable. All include
multi-XY groups w/ XY &
XX dominance hierarchies.
• Long-term studies on
Japanese macaques indicate
group innovations are
brought in by young XX’s.
• Example is “crab-eating”
macaque, Macaca
fascicularis. Group size is
10-50; food mostly fruit.
Macaca nemestrina sociality, #1
• Adult XX with offspring.
• As with baboons, macaque
babies inherit to some
degree the status of their
mothers.
• Also, the status of a XX
with infant is temporarily
raised.
• And XX’s who are
consistently successful
mothers often have higher
status.
Macaca nemestrina sociality, #2
• Adult XY, pucker-threat.
• Note the crouch, the
extended lips, and the
forward-directed posture,
which are diagnostic for
several types of threat.
• The pucker-threat is an
assertion of dominance that
typically elicits either
submission or a reciprocal
challenge (and then
possibly a fight).
Macaca nemestrina sociality, #3
• Adult XX, pucker-threat.
• XX almost always respond
submissively to XY threats,
but macaques are also
individuals.
• This XX (you’ve seen her
before) is able to
reciprocate the XY threat
because (1) he’s lowranking, (2) she’s usually
high-ranking, and (3) she
has an infant with her.
Macaca nemestrina sociality, #4
• Male-male mount.
• In primate societies things that
appear to be about sex are
often about power.
• To appease a higher-ranking
XY, a lower-ranking XY acts
submissively, “presenting”
sexually (an XX gesture).
• The higher-ranking XY
accepts, with a symbolic
mount.
• Note the young animal looking
on– and becoming socialized.
Macaca nemestrina sociality, #5
• Low-status adult XY, fearyawn.
• The lowered eyes, raised
brows, & retracted head
indicate fear, as does the
yawn itself.
• The exposed canines
indicate that attack would
nevertheless risk injury.
• Note that some facial
gestures have been
conserved for MY in
primates.
Macaca nemestrina sociality, #6
• Coalition of brothers.
• As with other social animals
(e.g., lions), displacement
of group leaders is often
accomplished by coalitions.
• In macaques, coalitions
almost always involve
(half-) brothers because
most lasting social
connections are established
through mothers.
The Ape Grade
• A general evolutionary trend among anthropoid
primates is increasing reliance on vision at the
expense of smell. The trend culminates in apes and
is associated w/increased hand-eye coordination &
enlargement of the brain.
• Ape-grade primates lack external tails. In all except
people, arms are longer than legs.
• Apes have long inter-birth intervals & extended
parental care (both anthropoid trends).
• All ape-grade primates (except people) are pantropical and endangered– by direct exploitation
and/or habitat destruction.
Family Hylobatidae
• This Family includes gibbons &
siamangs (1 genus, 11 species);
picture example is Symphalagus
syndactylus.
• These are small (10-12kg),
tailless, fruit-eating apes of S.E.
Asian rainforests.
• Monogamous fidelity is extreme.
Inter-birth intervals are c. 3
years. 2-parent care is extensive
(6-7 years).
• First birth is at about 9 years.
• Pairs “mark” territory by
brachiating displays & duets.
Orangutans (2 similar species)
• Pongo pygmaeus, from
Kalimantan, is illustrated;
another sp. on Sumatra.
• XX ave. 40kg; wild XY
twice as heavy.
• Adult XY avoid other XY
& use roars to maintain
territories overlapping
ranges of > 1 XX.
• XX are at first repro is
about 12-15yrs. Only
cohesive social unit is
mother + offspring.
Common chimp (Pan troglodytes)
• Chimps are forest animals
of Central & West Africa.
• XX 35kg; XY 45kg.
• Diet varies but is usually
dominated by fruit.
(Hunting traditions in
some groups….)
• XX sexually mature @ 14;
inter-birth interval c. 5
years.
• Unique because XY-XY
bonds form backbone of
social groups (XX outmigrate).
• Chimps share c. 98% of
genes with people.
Bonobo (Pan paniscus)
• The bonobo, or pygmy chimp,
inhabits central rainforest along the
Congo basin.
• Anatomically and genetically
similar to common chimp…
• …but radically different socially:
– Sex seems to be the glue that holds
bonobo society together.
– XX’s are migratory gender, but
relationships among them are strong.
– Even adult XY’s appear to take status
partly from mothers.
Gorillas (Gorilla gorilla; 3ssp.)
• Gorillas are, on ave., the
largest primates: XX 8595kg; XY c. 165kg.
• Habitat is dense forests,
swamps, etc.
• 2 lowland ssps eat fruit;
mountain ssp eats leaves
& shoots.
• Group size typically 5-20;
most include 1 (2) large
XY plus XX’s & young.
• Inter-birth interval 3-5
years.
• XX & XY out-migrate.
People (Homo sapiens)
• The most abundant primate
species.
• Large African primate most
closely related to chimps–
but radically divergent in
anatomy & behavior.
• People are world-building
(as opposed to worldaccepting) animals relying
on artificially constructed
ecosystems for almost all
material needs.