Shuster chat (9 Jan 2014)

[MKLau]

Going over results from the simulations.

Genetics generates biogeography

[MKLau]

Quick Intro

• R2 varies predictably over the surface of Vg-Ve
• Network structure was detected within a narrow range of Vg
• Really need Figure 2 instead, don't need stats because the numbers are the numbers

Questions

• Should we use H2C instead of R2?
• What can co-selection tell us about co-evolution?
• Are there other things that would be good to look at?

[MKLau]

[MKLau]

Foundation species genotypic variation should structure ecological interaction networks by altering co-occurrence frequencies

M.K. Lau, S.M. Shuster, K. Whitley, S. Borrett, T.G. Whitham

Abstract. Ecosystem function and dynamics are intrinsically linked to communities of organisms that interact in complex networks. Previous work has shown that both that community patterns have a genetic basis; however the related theory has not explored the potential for a genetic basis to complex interaction networks. In this study, we use simple, mass-action based simulations previously developed in Shuster et al. 2006 and network modeling to explore the possible effect that genetic variability in foundation species can influence the structure of ecological networks. Four main findings emerged: 1.) Environmental variation did not influence network size (measured by the number of significant co-occurrence patterns), but did contribute to spurious genetic patterns (i.e. observing a large genetic effect when selection intensity was low), 2.) Network size exhibited an exponential increasing response to the intensity of selection, 3.) All networks with significant structure had multivariate R2 values greater than 0.5, and 4.) Using co-occurrence probabilities to adjust the predicted frequency of interactions among species of an hypothesized networks, we found that interaction network structure was strongly impacted by underlying genetic variability on the foundation species. The results confirm that genetic variability in a foundation species can have significant effects on interaction network structure through its influence on species co-occurrence patterns. We can thus expect that even complex ecological networks should show significant effects of foundation species genetic variability even in communities of diffusely interacting species.

[MKLau]

Results: Gina's Data

         Df SumsOfSqs MeanSqs F.Model      R2      Pr(>F)

xtype 3 1.5779 0.52597 2.4113 0.16732 0.001 *** Residuals 36 7.8527 0.21813 0.83268 Total 39 9.4306 1.00000

[MKLau]

• Do both PerMANOVA and NMDS
• Change the number of genotypes
• At a certain point, you get a community phenotype

[MKLau]

R2 is related to H2C, but outperforms it in terms of detecting high levels of genetic effect.