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It is with regret that the analyses of Davis et al. (2012) were affected by an error in the authors' R code, which led to mistakes in phylogenetic comparative analysis. Reanalysis using corrected R code shows that although the absolute numbers are different to those previously published, nevertheless, qualitatively, the results are unaffected and the same conclusions can be drawn as before. Table 1 is provided with the correct values. Some particular aspects of these results are of note:

Table 1. - Individual trait tests for phylogenetic signal in egg size and maternal body size (bold), and optimal regressions of different variables on egg size and maternal body size. A and D = ACCTRAN and DELTRAN character optimizations, respectively. INF = infinite half-life
Trait (in bold) + Predictors Half-life: % tree height (t1/2) [support region] R 2 AICc
Egg Size 45 [9-INF]
+ Maternal Body Size8 [0-INF]56.0980.06
+ Diet (Poly/Oligophagy)A: 34 [6-INF]3.7111.67
D: 43 [4-INF]3.1109.44
+ Diet (Tree/Herb)A: 46 [4-INF]3.22111.79
D: 47 [6-INF]2.97109.47
+ HabitatA & D: 33 [4-INF]11.8104.99
+ Overwintering EggsA & D: 39 [11-INF]17.95101.41
+ Maternal Body Size and Diet (Poly/Oligophagy)D: 1 [0-INF]56.5182.87
+ Maternal Body Size and Diet (Tree/Herb)D: 2 [0-INF]56.4381.69
+ Maternal Body Size and HabitatA & D: 1 [0-INF]59.1481.61
+ Maternal Body Size and Overwintering EggsA & D: 9 [0-INF]59.4778.54
Maternal Body Size 82 [8-INF]
+ Diet (Poly/Oligophagy)A: 37 [0-INF]10.38125.27
D: 36 [9-INF]7.54124.49
+ Diet (Tree/Herb)A: 27 [6-INF]17.87121.94
D: 45 [9-INF]14.22120.35
+ HabitatA & D: 42 [9-INF]11.34122.1
+ Overwintering EggsA & D: 59 [17-INF]8.76123.24

Although egg size was previously shown to have a very small phylogenetic half-life, the half-life point estimate is now much greater (45%). However, compared with maternal body size, evidence still suggests that egg size is a more rapidly evolving trait than maternal body size (phylogenetic half-life point estimate = 82%) and can be analysed in an Ornstein–Uhlenbeck framework as before (i.e. egg size as response to maternal body size as predictor).

The important conclusion that maternal body size as a single trait is the best predictor of egg size in geometrid moths remains the same showing an R2 value (56%) similar to that of the previously published article. Whether the egg is the overwintering stage of a species or not is shown in reanalysis to have a much greater R2 value than previously and may be of some predictive value, but is still shown to be a considerably less good predictor of egg size than maternal body size. Mixed model predictors are shown not to greatly increase predictive ability compared with maternal body size alone. This is an unchanged conclusion from the previously published article. Furthermore, maternal body size is not greatly explained by any discrete predictors as shown in the previous analysis.

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