How To Be a Monkey

Taxonomy

Prosimians

Old World Monkeys

New World Monkeys

Apes

Why did primates evolve to be so smart?

3 main hypothesis

1. Extractive foraging

2. Mental map making

3. Social life

Advantages to living in a group

• Can more effectively monopolize resources
• Males have access to females
• More eyes and ears to watch for predators

Group structures vary accross species

• Stable vs fission-fusion
• Matrilinial vs patrilinial
• Monogamy vs promiscuity
• Multi-male vs single-male
• Variation in group size

Capuchin group structures

• Usually 15-25 monkeys
• Matrilinial — females stay in group
• Males migrate when they reach adulthood, around 7 years old

Female hierarchies

In most species, females inherit the rank of their mothers

• Leaf eating (abundant distribution) → relaxed social structure
• Fruit eating (monopolizable) → strict hierarchy

Male hierarchies

Male hierarchies are determined by body size

• Females cycle separately → strict hierarchy
• Female cycles synchronized → relaxed hierarchy

In capuchin monkeys, adult males migrate to another group

Capuchin monkey behaviors

What do they do all day?

Foraging

Capuchin monkeys spend most of their day foraging

Traveling from fruit tree to fruit tree all day, covering 3-5km on average

Learning to forage

Juviniles closely watch and imitate the adults

Grooming

Enforces social bonds

Grooming goes "up the social hierarchy"

Sex

Sex is used for a variety of social functions — reproduction, conflict resolution, dominance assertion, social bonding

Promiscuity evolved to confuse paternity

Displays

Physical fights are risky and therefore rare. Monkeys threaten each other instead

Coalitions

Aggression + social bonding

Coalitions

Coalitions

Play

Parenting

Female capuchins love to play with babies

Social fur rubbing

With guapanol, limes, chilles

Insect repellant?

Cognition

Can you really know a monkey's thoughts and emotions?

Do monkeys have empathy?

Language aquisition studies in apes

Tool use + complex problem solving

Gorillas can invent new signs for words they don't know!