Primate Social Behavior 2

Anthropology 2200

Non-residential pattern aspects primate behavior

• Competition • Cooperation • Culture • Parenting behaviors • Tool use • Language

Social Strategies

Male Competition

• Male reproductive strategy  competition for mates

• Produce lots of offspring • Prevent other males from doing

the same thing • Intimidation • Fighting • Leads to sexual selection

• Body size / canine dimorphism

Mandrill: Coloration = health Tooth size

Uakari: Color = health and dominance

Male Competition

• Sperm competition

• Relationship between:

• Testes size

• Penis size

• More competition = larger size

Female Competition

• Female reproductive strategy  competition for resources

• Ensure the survival of offspring

• Dominance relationships • Access to resources

Female Baboon hierarchy

Competition

• Aggressive behaviors • Direct eye contact • Raising eyebrows • Baring canines • Charging

Gelada Baboons

Competition

• Subordination • Ritualized behavior

• Showing backside • Cowering • Presenting to groom • Greeting with friendly facial

expressions and vocalizations

• Intended to ease tension • Prevent conflict

Unequal Pay – Primate Jealousy

• Differences in food quality • Personal jealousy?

Capuchin monkeys and equity

Cooperation

• Affiliative behaviors • Promote group

cohesion • Assurance • Pleasure • Reciprocity

Cooperation

• Form of Altruism • Behavior that benefits others while being a

disadvantage to the individual • Grooming/playing • Hunting/Food sharing • Caregiving • Attacking predators • Giving warning calls

• Kin selection • Behavior that increases the fitness of those

closely related to the individual • Usually the focus of altruistic behavior • Increases the donor’s inclusive fitness

• Reproductive success of organism and close kin

Cooperation

• Grooming to remove parasites and dead skin

• Maintains close contact between family members and non-related group members

• Eases tension • Promotes group cohesion

Chimpanzee grooming

Cooperation

• Playing • Maintains close contact between family

members and non-related group members • Eases tension • Promotes group cohesion

Bonobos Playing

Cooperation

• Caring for young that are not yours • Alloparenting

• Individual other than parent cares for the infant

• Usually done by females (in some species, males also contribute)

Capuchin Monkey

Squirrel Monkey

Cooperation

• Attacking predators and giving warning calls • Allows other members of the group to

escape

• Might lead to injury or death

Vervet Monkey did not survive….

Baboon did survive

Cooperation

• Group Hunting/Foraging • Find food more efficiently • Might find food/hunt prey that you

could not get as an individual • Have to share • Might get injured during hunt

Chimpanzee hunting

Cooperation

• Warfare • Observed in chimps • Group fights between chimps over

territory • Often kill neighboring males • Territory = access to food resources

Chimpanzee patrol composed of primarily

males

Chimpanzee raids

Chimpanzee politics

So where do these behaviors come from? Parenting

• Prolonged period of development • Prolonged period of parental care • Allows parents to teach offspring how to succeed

socially/in environment • Parents VERY important!

Parenting • 1950s psychological experiments (Harry Harlow)

• Demonstrated parenting = not just nourishment • Monkey’s taken from mothers shortly after birth • Raised alone in cages: wire “nourishing” mother, cloth

mother, no mother • Preferred cloth mother = warmth, comfort, security • No mother = distressed, refused to eat, died

Parenting

• Specifics – what do primates learn from their parents?

• Non-verbal and verbal communication

• Social behavior: competition and cooperation

• Tool use • Parenting behavior • Culture!

How do we know its culture and not just inborn behavior?

• Harlow’s Experiments • Japanese Macaques

• Beach of Koshima • Wash sweet potatoes in salt water • 1 decade idea spread • From very few to most

Japanese macaques

The unique side of bonobos

Culture: Examples • Tool use: Chimpanzees

• Spears and their use for hunting bush babies • Termite fishing • Chewed leaves as sponges • Rocks for breaking open nuts

Chimps spearing

Termite fishing

Culture: Examples

• Chimp grooming traditions • Differ depending on the group

• Gombe National Park, Tanzania • Groom each other by holding an overhead branch with one hand

and grooming a partner with the other • Mahale National Park, Tanzania

• Clasp hands while grooming

Gombe Mahale

Communication

• Voluntary (intentional) • e.g. postures,

vocalizations, and facial expressions

• Autonomic (unintentional)

• e.g. estrus

Voluntary Communication Example: Gorilla

• Sharp grunting: a sign of disapproval. • Chuckling: a sign of playfulness. • Screaming: a sign of alarm or warning. • High-pitched barking: a sign of curiosity. • Roaring: a sign of aggression. • Belching: a sign of contentment

Language

• Significant human development

• Communication in non- human primates:

• Emotional • Only in the present • Predator alarm system • Establish territories

Language

• Non-human primates • Many have been taught ASL

• Don’t have vocal range for human language/no syntax

• Teach others ASL • Can make references to external

objects • E.g. “go get ball outside”

• Can identify images of things in addition to the things themselves

Koko with All Ball

Koko’s sign language

Primate Taxonomy 1

Anthropology 2200

Examine primate classification Pygmy Marmosets

• SIZE DIVERSITY IN PRIMATES

Mouse lemur (Microcebus berthae) 3.6 inches, 1.1 oz

Adult Gorilla (Gorilla gorilla) 440 lb

loris gibbon

aye aye gorilla

chimpanzee

tarsier

capuchin orangutan

spider monkey baboon

ring tailed lemur

Japanese macaque bonobo

howler monkey

mouse lemur

Primates • What is a Primate?

• Kingdom  Animalia • Phylum  Chordata • Class  Mammalia • Order  Primates • Suborders:

• Strepsirhines (Lemur, Loris, Galago) • Infraorder: Lemuriformes

• Haplorhines (Tarsiers, Monkeys, Apes, and Humans)

• Infraorders: • Tarsiiformes • Anthropoidea (Parvorders =

Platyrrhini and Catarrhini) • Slender Loris

Taxonomy

Cladistic Taxonomy: Haplorhini/Strepsirrhini Nomenclature preferred by many

• Places Tarsiers in with Haplorhines • Many believe this system is more evolutionarily accurate!

Tarsiers

Strepsirhines vs. Haplorhines

• Strepsirhines: lemurs, lorises, galagos

• Haplorhines: everything else (tarsiers, New World Monkeys, Old World Monkeys, Apes, humans)

• They split around 55-80 million years ago

Slender Loris Galago/Bush Baby Ring Tailed Lemur

Strepsirhines

Ring-tailed lemur

Strepsirhines

• Found in Africa and Asia (13% of Primates)

• Retain many primitive characteristics

• This does not mean that they are the ancestors of monkeys!!!

High rates of nocturnality • Primitive Trait

• Tapetum lucidum • Layer behind the

retina • Reflects visible light

back through the retina

• Improves vision in low light conditions

Sportive Lemur Retina

Post Orbital Bar: No Closure

Primitive Trait

Partially stereoscopic vision (primitive)

Lack color vision (primitive)

Reliance on Olfaction • Communication for nocturnal animals

• Ancestral trait • Scent glands

• Marking • Messages

• Large olfactory bulb • Part of brain for scent

• Rhinarium  moist nose • readily picks up

scents

Mouse Lemur

Ring Tail Lemur

Grooming claw • Primitive Trait

• Lemurs, Galagos, Lorises: 2nd Toe (Aye-Aye = 2-5)

• Purpose: • Grooming • Extracting insects

Ruffled Lemur

Galago

Tooth comb

• Derived Trait • Used for:

• Grooming • Extracting resin

from trees Ring Tailed Lemur

Lemuroidea : Lemurs

• Only found on the island of Madagascar

• Only non-human primate found there

• Lots of diversity • 20 mya split from Africa • Adaptive radiation • Represent 21% of primate

genera worldwide

Lemuroidea : Lemurs

• Ring-tailed lemur • More terrestrial • Black and white ringed tail • Omnivorous • Diurnal • Forest and spiny scrub • Highly social • Female dominant

• Common in Lemurs • Sent marking • Stink Fighting

Lemuroidea : Lemurs

• Mouse lemur • Smallest primate • < 1 lb. • Eat insects, small vertebrates,

gum, fruit, flowers, nectar, leaves

• Nocturnal

Grey mouse lemur

Additional Traits

Tend to have more specialized diets and behaviors than anthropoids (derived)

• Often fill very specific niches • Lemurs on Madagascar

Vertical clinging and leaping Often solitary

Sifaka Clinging

Sifaka

Lemuroidea : Aye-aye

Aye-aye • Nocturnal • Mainly insectivorous • Thin middle finger to forage for

grubs  Taps to find grubs  Gnaws bark  Uses finger to pull out grubs

• Solitary

Aye-aye

Lorisoidea: Lorises

• Lorises • Tropical Africa and

Southeast Asia • Nocturnal • Slow-moving,

deliberate stalkers of small prey

Lorisoidea: Lorises

• Slow loris • Toxic bite

• Lick gland on their arm • Secretion activates with

saliva (adult/baby) • Communicate by sent

marking • Eat small animals, fruit, gum,

vegetation • Hunted for exotic pet trade

The Bite of a Slow Loris How poisonous is the slow

loris? • Allergen similar to Felid 1  Cat allergen in dander  Anaphylactic shock  Red blood cells in urine

Depends how allergic you are!

Lorisoidea: Galagos

• “Bush-babies” – Subfamily of Lorises

• Sub-Saharan Africa • Nocturnal • Vertical clingers and leapers • Insectivorous

Lorisoidea: Galagos Can turn its head over 180

degrees Index finger more widely

spaced • Feeding • Gripping branches

Nocturnal • Large Eyes • Large Ears

Haplorhini

Tarsiers, monkeys, apes, and humans

• Larger body • Larger brain-to-body size ratio • More sexually dimorphic • Less specialized dentition (fewer premolars) • Greater reliance on vision than on smell • Post-orbital closure • Diurnal rather than nocturnal

Differ from Strepsirhines in a variety of ways

Tarsiers vs. all other Haplorhines

• Tarsiers are taxonomically problematic

• Prosimian/anthropoid

• Strepsirhine/haplorhine • They possess a mixture of

primitive and derived traits • Divergence time of ca. 50-

70 Million years ago?

Infraorder: Tarsiiformes (Tarsiers) • Tarsiers

• Southeast Asia • Nocturnal

• eye larger than brain • Vertical clingers and

leapers • Grooming claw: 2nd and 3rd

Toes • Highly carnivorous

• Lizards, frogs, insects

Tarsiiformes: Tarsiers

Name refers to two elongated tarsals – extra leverage for leaping

Tarsiers

Primate Taxonomy 2

Anthropology 2200

Infraorder: Anthropoidea

Infraorder: Anthropoidea Two Parvorders

Platyrrhini “Broad-nosed

Catarrhini “Hook-nosed”

2:1:3:3/2 2:1:2:3

Anthropoids: Platyrrhini • Central/South American

Monkeys

• Latin and South America

Platyrrhini: Ceboidea

• Central/South American monkeys • Arboreal quadrupeds

• Suspensory locomotion • Many = Prehensile tail • Not in African/Asian Monkeys

• Diverse diet • Leaves, fruit, insects

Spider Monkey

Platyrrhini: Ceboidea

• Two Families • Atelidae

• Howler, Owl, Spider, Titi, and Woolly monkeys, Uakaris, and Sakis

• Cebidae • Marmosets, Tamarins,

Capuchins, Squirrel Monkeys

Platyrrhini: Ceboidea: Cebidae

• Marmosets/Tamarins • Retain claws instead of

nails • Smallest Platyrrhini • Twin (Chimerism) • Insectivores • Unusual dental

formula • 2:1:3:2

Golden Lion Tamarin Silvery Marmoset

Emperor tamarin

Platyrrhini: Ceboidea: Cebidae

• Capuchin monkeys • Name from Order of Friars

Minor Capuchin • Often in Movies!

White Fronted Capuchin

Platyrrhini: Ceboidea: Atelidae

• Includes subfamilies: • Aotidae • Pitheciidae • Atelidae • Alouattinae

Platyrrhini: Ceboidea: Atelidae

• Owl/Night Monkey • Only truly nocturnal monkey

• Vocal calls/Sent Marking • Susceptible to human forms of

Malaria • Used for malaria research

Platyrrhini: Ceboidea: Atelidae

• Pitheciidae • Titis • Sakis • Uakaris

White Faced SakiUakari

Titi Monkeys (morning calls) Uakari Saki

Bald uakari monkey

Platyrrhini: Ceboidea: Atelidae

• Spider monkeys • Wooly monkeys

• Only