Figure 2. A visualization of Lewontin’s Paradox of Variation.

Pairwise diversity (data from Leffler et al., 2012, Corbett-Detig et al., 2015, and Romiguier et al., 2014), which varies over three orders of magnitude, shows a weak relationship with approximate population size, which varies over 12 orders of magnitude. The shaded curve shows the range of expected neutral diversity if $N_e$ were to equal $N_c$ under the four-alleles model, ${\displaystyle {\log }_{10}(\pi )={\log }_{10}(\theta )-{\log }_{10}(1+4\theta /3)}$ where $\theta =4N_c\mu$, for two mutation rates, $\mu ={10}^{-8}$ and $\mu ={10}^{-9}$, and the light gray dashed line represents the maximum pairwise diversity under the four alleles model. The dark gray dashed line is the OLS regression fit, and the blue dashed line is the regression fit using a phylogenetic mixed-effects model. Points are colored by phylum. The species Equus ferus przewalskii ($N_c\approx {10}^3$ and $\pi =3.6\times {10}^{-3}$) was an outlier and excluded from this figure for visual clarity.

Figure 2—figure supplement 1. A linear-log version of Figure 2.

Points are colored by phylum, and the shaded region is the predicted neutral level of diversity assuming $N_e=N_c$ with mutation range ranging between ${\displaystyle {10}^{-9}\le \mu \le {10}^{-8}}$.

Figure 2—figure supplement 2. A version of Figure 2 with OLS estimates per phylum.

Diversity and approximate population size for 172 taxa, colored by phylum; the dashed lines indicate the non-phylogenetic OLS estimates of the relationship between population size and diversity grouped by phyla.

Figure 2—figure supplement 3. The posterior distributions and fitted relationship between diversity and both body mass and range size.

The relationship between diversity (differences per basepair) and body mass (left) and range (right) across 172 species. The top row are posterior distributions of parameters estimated using the phylogenetic mixed-effects model using 166 taxa in the synthetic phylogeny for the intercept, slope, and phylogenetic signal from the mixed-effects model. The bottom row contain each species as a point, colored by phyla. The gray dashed line is the non-phylogenetic standard regression estimate, and the blue dashed line is the relationship fit by the phylogenetic mixed-effects model.

Figure 2—figure supplement 4. Pairwise diversity grouped by the range categories from Leffler et al., 2012, with point size indicating the predicted population density.

The vertical lines are the range category group means.