differentials: Estimate phenotypic selection differentials In MorphoFun/psa: Phenotypic Selection Analysis tools

Description

`differentials` allows the user to evaluate how different methods for calculating phenotypic section differentials influence the output and, thus, the interpretation of indirect selection on phenotypic traits.

Usage

 `1` ```differentials(w, z, method = c(1,2,3,4, "all"), standardize = TRUE, ...) ```

Arguments

 `w` Relative fitness. `z` Phenotypic trait(s). Character values are not accepted. `method:` method to estimate the selection differential. 1 = covariance of relative fitness to the trait; 2 = differences in mean, variance, and covariance before and after selection; 3 = matrix algebra approach of phenotypic distributions before and after selection; 4 = ordinary least-squares regression of relative fitness against the trait; "all" = use all of the methods to produce multiple estimates. `standardize` Indicate whether phenotypic trait data should be standardized to a mean of zero and unit variance.

Value

`differentials` returns a data.frame

Output

`dCov` is the selection differential calculated from the covariance between the relative fitness, `w`, and each phenotypic trait `z` (Lande and Arnold 1983).

`dBeforeAfter` is the selection differential calculated as as described in Brodie et al. (1995).

`dMatrix` is the selection differential calculated using matrix algebra (e.g., equation 13b in Lande and Arnold (1983))

`dReg` is the selection differential calculated as the partial regression coefficient of relative fitness, `w`, against each individual phenotypic trait through univariate linear regressions.

`dCovScale` calculates the selection differential using the equation in `dCovScale`, but uses z data that are standardized to a mean of zero and unit variance.

References

Brodie III ED, Moore AJ, Janzen FJ. 1995. Visualizing and quantifying natural selection. Trends in Ecology and Evolution 10(8): 313-318. http://www.sciencedirect.com/science/article/pii/S016953470089117X

Lande R, Arnold SJ. 1983. The measurement of selection on correlated characters. Evolution 37(6): 1210-1226. http://www.jstor.org/stable/2408842

Examples

 ```1 2 3``` ```data(BumpusMales) differentials(BumpusMales\$w, BumpusMales[,3:11], "all") ```

MorphoFun/psa documentation built on May 7, 2019, 4:59 p.m.