Did natural selection make the Dutch taller? A cautionary note on the importance of quantification in understanding evolution.
One of the main achievements of the modern synthesis is a rigorous mathematical theory for evolution by natural selection. Combining this theory with statistical models makes it possible to estimate the relevant parameters so as to quantify selection and evolution in nature. Although quantification is a sign of a mature science, statistical models are unfortunately often interpreted independently of the motivating mathematical theory. Without a link to theory, numerical results do not represent proper quantifications, because they lack the connections that designate their biological meaning. Here, we want to raise awareness and exemplify this problem by examining a recent study on natural selection in a contemporary human population. Stulp et al. (2015) concluded that natural selection may partly explain the increasing stature of the Dutch population. This conclusion was based on a qualitative assessment of the presence of selection on height. Here, we provide a quantitative interpretation of these results using standard evolutionary theory to show that natural selection has had a minuscule effect.
Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway. maja.tarka@ntnu.no.
Maja
M
Tarka
Norwegian Institute for Nature Research (NINA), Centre for Biodiversity Dynamics, 7485, Trondheim, Norway.
Geir H
GH
Bolstad
Department of Biology, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway.
Sebastian
S
Wacker
Department of Aquatic Ecology , Swiss Federal Institute of Aquatic Science and Technology, Eawag, 8600, Duebendorf, Switzerland.|Institute of Integrative Biology, ETH Zurich, 8092, Zurich, Switzerland.
Katja
K
Räsänen
Department of Biology, CEES & Evogene, University of Oslo, 0316, Oslo, Norway.
Thomas F
TF
Hansen
Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway.
Christophe
C
Pélabon
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001827:Body Height; D002648:Child; D002675:Child, Preschool; D004777:Environment; D056084:Genetic Fitness; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D012641:Selection, Genetic; D055815:Young Adult
Significance testing; human evolution; natural selection; quantitative genetics