Projects per year
Abstract
Showing that the arithmetic mean number of offspring for a trait type often fails to be a predictive measure of fitness was a welcome correction to the philosophical literature on fitness. While the higher mathematical moments (variance, skew, kurtosis, etc.) of a probabilityweighted offspring distribution can influence fitness measurement in distinct ways, the geometric mean number of offspring is commonly singled out as the most appropriate measure. For it is wellsuited to a compounding (multiplicative) process and is sensitive to variance in offspring number. The geometric mean thus proves to be a predictively efficacious measure of fitness in examples featuring discrete generations and within or betweengeneration variance in offspring output. Unfortunately, this advance has subsequently led some to conclude that the arithmetic mean is never (or at best infrequently) a good measure of fitness and that the geometric mean should accordingly be the default measure of fitness. We show not only that the arithmetic mean is a perfectly reasonable measure of fitness so long as one is clear about what it refers to (in particular, when it refers to growth rate), but also that it functions as a more general measure when properly interpreted. It must suffice as a measure of fitness in any case where the geometric mean has been effectively deployed as a measure. We conclude with a discussion about why the mathematical equivalence we highlight cannot be dismissed as merely of mathematical interest.
Original language  English 

Article number  12 
Pages (fromto)  122 
Number of pages  22 
Journal  Biology and Philosophy 
Volume  37 
Issue number  2 
DOIs  
Publication status  Published  Apr 2022 
Keywords
 fitness
 propensity
 growth rate
 geometric mean
 artithmetic mean
 population biology
 evolutionary theory
 selective explanation
 Propensity
 Growth rate
 Selective explanation
 Evolutionary theory
 Geometric mean
 Population biology
 Arithmetic mean
 Fitness
Fingerprint
Dive into the research topics of 'The arithmetic mean of what? A cautionary tale about the use of the geometric mean as a measure of fitness'. Together they form a unique fingerprint.Projects
 1 Active

DE210100303: Inheritance and the Emergence of Individuals: From concepts to practice
29/12/21 → 31/12/23
Project: Research