Equation 1 · Part 1 · The Longest Childhood: Life-History Theory and the Grandmother Bet
Symbol d
What this part means
d is part of the quantity the equation computes from the expression on the right.
Its job in the formula
d is part of the quantity the equation computes from the expression on the right.
Full expression→Symbol d→Article meaning
The passage around this formula
Put the three numbers next to each other and the puzzle sharpens rather than resolving. A species that weans early is, on the usual mammalian logic, moving resources toward producing more offspring faster. A species that delays first reproduction by five years relative to a close comparator is, on the same logic, moving resources the other way, into growth and skill before any output. A species in which a large share of the reproductively spent population survives for decades afterward is carrying dependents — grown or not — who cannot be explained by ordinary offspring investment, because offspring investment stops paying by the time the investor can no longer reproduce. The three facts do…
Learn the underlying idea
A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.
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Sources cited in the surrounding passage
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