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Biology Quote by Ronald Fisher

“We may consequently state the fundamental theorem of Natural Selection in the form: The rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time.” quote by Ronald Fisher
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“We may consequently state the fundamental theorem of Natural Selection in the form: The rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time.”

Ronald Fisher

About This Quote

Source Book: The Genetical Theory of Natural Selection, 1930

Fitness rises proportionally to how much genetic variation exists in a population at a given moment.

In simple terms: More genetic variation means faster fitness improvement.

Key Takeaway

Preserve genetic diversity.

Themes

evolution genetics population dynamics

Mood

analytical objective

Type

scientific educational

When to use this quote

  • conservation breeding
  • crop improvement
  • medical genetics
  • environmental change

Key Concepts

natural selection genetic variance fitness landscape

Questions to Reflect On

  • How does maintaining diversity affect long‑term adaptation?
  • What limits the rate of fitness increase?
A Different Perspective

Assumes additive genetic effects and ignores epistasis.

2.3 out of 5 (7 ratings)

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