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Equation 6 · Part 7 · From Origins to Frontier: A History of Evolutionary Biology and Ecology

subscript

pt+1=pt(1+s)1+s pt.p_{t+1} = \frac{p_t(1+s)}{1 + s\,p_t}.
subscript

What this part means

The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.

Its job in the formula

A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.

The passage around this formula

A basic case illustrates the kind of prediction this apparatus makes possible. For a single locus with two alleles under simple directional selection with selection coefficient s favoring an allele at frequency p , one classical discrete-generation recursion is pt+1=pt(1+s)1+s ptp_{t+1} = \frac{p_t(1+s)}{1 + s\,p_t}. This is a deliberately simplified model — haploid, one locus, constant s , no drift, no linkage — and real populations violate several of its assumptions routinely. Its value is not as a literal forecast of any specific population but as a baseline against which departures (frequency-dependent selection, epistasis, drift-dominated dynamics in small populations) can be identified and measured.

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

Open the illustrated subscripts: which member of a family? guide →

Sources cited in the article section

These citations provide research context; check each source for the exact claim it supports.