Biology Quote by Karl Pearson
““The starting point of Darwin 's theory of evolution is precisely the existence of those differences between individual members of a race or species which morphologists for the most part rightly neglect. The first condition necessary, in order that any process of Natural Selection may begin among a race, or species, is the existence of differences among its members; and the first step in an enquiry into the possible effect of a selective process upon any character of a race must be an estimate of the frequency with which individuals, exhibiting any given degree of abnormality with respect to that, character, occur. The unit, with which such an enquiry must deal, is not an individual but a race, or a statistically representative sample of a race; and the result must take the form of a numerical statement, showing the relative frequency with which the various kinds of individuals composing the race occur.””
About This Quote
Source Book: The Grammar of Science by Karl Pearson, 1892
Darwin’s evolution relies on variation among members of a species; natural selection acts on these differences, requiring statistical measurement of their frequencies.
In simple terms: Evolution needs variation and statistical analysis of traits.
Key Takeaway
Measure trait frequencies to understand selection.
Themes
evolution
variation
statistics
natural selection
Mood
analytical
inquisitive
Type
scientific
educational
When to use this quote
- biodiversity studies
- conservation planning
- medical genetics
- agricultural breeding
Key Concepts
population genetics
frequency distribution
sample analysis
Questions to Reflect On
- How do you quantify variation in a small population?
- What biases affect frequency estimates?
A Different Perspective
Statistical data may be hard to collect for rare traits.
![“There is no gene "for" such unambiguous bits of morphology as your left kneecap or your fingernail. [...] Hundreds of genes contribute to the building of most body parts and their action is channeled through a kaleidoscopic series of environmental influences: embryonic and postnatal, internal and…” quote by Stephen Jay Gould](https://sms4smile.com/quotes/img-quotes/13d/stephen-jay-gould-885_action_there-is-no-gene-for-such-unambiguous-bi_511416.jpg)
