Companies that recognize the full talents of the entire population outperform those that do not.
Conversely, large populations outperformed small populations within native environments, but only at later life stages.
Local adaptation in salmonid fishes seems to occur with high frequency [ 12] and a recent review showed that in 55-70% of all comparisons, native populations outperformed non-natives [ 8].
We made two predictions with regard to survival: 1) within sites: native populations outperform non-natives; 2) across sites: populations show higher performance at 'home' compared to 'away' sites.
To test our second prediction (populations outperform others at 'home' but not at 'away' sites) we ran five more GLMMs on survival, separately per population, using Location as fixed effect and Capsule and Position as random effects.
To specifically test our first prediction (native populations outperform non-natives within sites) we ran another five GLMMs on survival, separately per location, using Population as fixed effect and Capsule and Position as random effects.
Local adaptation is defined as an interaction between ecotype and site (E × S), with ecotypes from local populations outperforming nonlocal transplants in subenvironments such as different climates (Linhart and Grant 1996).
The larger the transplanting matrix, however, the less likely it is that native populations outperform non-natives in every case, and the prediction must be reformulated such that, across all population-by-habitat combinations, mean population fitness should be higher for natives than for non-natives [ 2].
No subject population consistently outperformed the others.
In the AMX lines the level of improvement did not rise to statistical significance; however, the trend was consistent with the one predicted by evolutionary adaptation (and some stressed populations even outperformed their matched controls), suggesting that simple heterosis may not be the only force operating in populations with high genetic diversity.
