The Origin of Species · Chapter
Wide-Ranging, Much Diffused, and Common Species Vary Most explained
Darwin argues that species with wide geographical ranges, high abundance, and dominance within their own country are most likely to produce well-marked varieties (incipient species).
What happens
Darwin argues that species with wide geographical ranges, high abundance, and dominance within their own country are most likely to produce well-marked varieties (incipient species). He cites the assistance of Mr. H. C. Watson and Dr. Hooker in tabulating data from floras, and notes that dominant species, by inheriting advantages from their parents, are best positioned to succeed in the struggle for existence.
Themes in this chapter
Variation and Inheritance
The chapter focuses on which species vary most and how dominant species produce incipient varieties through inheritance of advantages.
Natural Selection and the Struggle for Existence
Darwin links variation to the struggle for existence, noting that varieties must compete with other inhabitants and that dominant species are more likely to succeed.
Characters to notice
- Mr. H. C. Watson
Provided valuable advice and assistance on tabulating varieties in floras.
- Dr. Hooker
Confirmed the difficulties of the task and endorsed the conclusions after reviewing the manuscript and tables.
- De Candolle
Showed that plants with wide ranges generally present varieties.
Key passages
“Guided by theoretical considerations, I thought that some interesting results might be obtained in regard to the nature and relations of the species which vary most, by tabulating all the varieties in several well-worked floras.”
Darwin believed that analyzing the varieties recorded in well-studied plant catalogs could reveal patterns about which species tend to vary most.
Introduces the method of tabulating varieties to study variation.
“Hence it is the most flourishing, or, as they may be called, the dominant species—those which range widely, are the most diffused in their own country, and are the most numerous in individuals—which oftenest produce well-marked varieties, or, as I consider them, incipient species.”
The species that are most successful and widespread are the ones most likely to produce distinct varieties, which Darwin views as the first steps toward new species.
Key conclusion linking dominance to the production of incipient species.