Chapter 1 - Introduction to Evolution

When did the universe originate, according to science?

~14 billion years ago.

When did Earth and the solar system form?

~4.6 billion years ago, from gravitational condensation of gas and dust

When did life begin on Earth, and how?

>3.5 billion years ago, from self-replicating molecules formed chemically

What does Darwin's "tree of life" represent?

The idea that all organisms are related through descent with modification

Humans share a common ancestor with chimpanzees. When did this ancestor live?

~6 million years ago

Mammals share a common ancestor with reptiles. When did it exist?

~300 million years ago

All vertebrates trace ancestry to what kind of creature?

A primitive fish-like organism that lived >500 million years ago

<450 years ago, what did Europeans believe about the universe?

That Earth was the center, with Sun, planets, and stars orbiting it (geocentrism)

<250 years ago, what had changed?

Heliocentrism and a larger universe were accepted, but many still believed the universe was created ~6000 years ago

<150 years ago, what was accepted and what was still rejected?

Geological change over millions of years was accepted, but species were still believed to be specially created by God

Why was Darwin's concept of "descent with modification" revolutionary compared to earlier views?

It replaced the idea of fixed, specially created species with the idea that species evolve gradually from common ancestors

What is the scientific assumption about the universe?

That it can be understood without appealing to religious or governmental authority

How did science reshape society?

It transformed philosophy, religion, and culture — sometimes destabilizing traditional beliefs

What caused the disasters of the 20th century according to the text?

Failures of rationality, not rationality itself

Why is the rational, wise use of science essential for the future?

Because misusing or ignoring science risks global catastrophe (e.g., climate change, nuclear war, pandemics)

How does evolution connect humans to other species?

It shows humans are deeply related to all organisms via shared ancestry

Why is evolution practically important for medicine?

Because pathogens (bacteria, HIV, viruses) evolve resistance to treatments

If a new antibiotic is introduced, why might it become ineffective over time?

Bacteria can evolve resistance via natural selection