The Origin of Species · Chapter
Extinction Caused by Natural Selection explained
Darwin argues that natural selection, operating through the preservation of advantageous variations, inevitably leads to the extinction of less favored forms.
What happens
Darwin argues that natural selection, operating through the preservation of advantageous variations, inevitably leads to the extinction of less favored forms. As new species arise, they outcompete their closest relatives, causing rarity and eventual extinction, a process analogous to the replacement of older domestic breeds by improved ones.
Free preview opens on this chapter — companions, themes, and character notes appear beside the text.
Narrative arc
Story tension across the book — this chapter sits in Exposition.
- Setup
- Escalation
- Breaking point
- Aftermath
- Closing
This passage marks the story's dramatic climax because Darwin shifts from a defensive posture against objectio…
Full beat labels and climax notes unlock in the reader.
Follow the arc while readingThemes in this chapter
- Natural Selection and the Struggle for Existence
Natural selection is the mechanism driving extinction by favoring advantageous variations and eliminating less favored forms.
- Extinction and the Succession of Forms
Extinction is a direct consequence of natural selection, as new species replace older, closely related forms through competition.
Characters to notice
- Charles Darwin
Author and narrator, presenting the argument that natural selection causes extinction.
Key passages
“Natural selection acts solely through the preservation of variations in some way advantageous, which consequently endure.”
Natural selection works only by keeping beneficial variations, which then persist over time.
Darwin clarifies the exclusive mechanism of natural selection.
“Rarity, as geology tells us, is the precursor to extinction.”
Geology shows that becoming rare is the step before going extinct.
Darwin links rarity to extinction using geological evidence.
“The forms which stand in closest competition with those undergoing modification and improvement, will naturally suffer most.”
The species that compete most directly with the ones being improved will be the ones that suffer the most.
Darwin identifies that close relatives face the greatest pressure from natural selection.
