Humans (Homo sapiens), Primitive → Modern Humans, and Fear and Human Evolution

Defining traits?

Large brain, language.

Posture?

Upright, bipedal.

Face shape?

Flat with small jaw.

Infant dependency?

Very long.

Sexual dimorphism?

Mild (1.2× male/female weight).

Bipedalism disadvantage?

Childbirth & joint issues.

Bipedalism advantage?

Hands free, efficient movement.

Shift to agriculture?

≈12,000 years ago.

First domesticated animal?

Dog.

Result of agriculture?

Deforestation & extinctions.

European predators lost?

Lions and wolves.

Effect on evolution?

Humans altered ecosystems too quickly.

Why did primates evolve fear?

Defense from predators.

Modern fear triggers?

Movies, anxiety, stress.

Why fear darkness or snakes?

Evolutionary instinct.

What is the "fear module"?

Automatic threat response.

Modern problem with fear?

Chronic stress from imagined danger.