Moore Notes 2 23 11

Group Call - Niche Mapping subgroup

• Josh and Katie working on manuscript
  • Getting text and figures from James, Tom, and Alex
  • James will finish figure today. Second paragraph of his text is for methods section.
  • Goal: circulate manuscript on Friday or Monday for full group to comment.

• Alex: phylum level analysis plots
  • Some phyla are richer at tropics, others in temperate latitudes
  • Adjusting for number of genera per phylum
    • when look at 20 random subsets of 5 Proteobacteria genera, the dip in richness at equator is significantly reduced
    • Steve: may need more draws. Alex has this data, and can check.
    • Josh will check that genera not in subset of 5 are being added back to the baseline "unclassified" group
  • Tom: Why doesn't cyanobacteria richness map match chlorophyll concentration?
    • Didn't use primary productivity as a predictor, so interesting that we see this pattern independently
    • Should check abundance instead of richness for this question
    • Steve: some diverse places don't have a ton of biomass (Mediterranean) - need to deflect criticisms of genus-level analysis being meaningless

• Reviewers
  • Biodiversity people over microbial oceanographers
  • Josh will check process at Science

• Josh: bias in GLMs
  • Getting higher probabilities than we should
    • No zeros
    • Jensen's inequality means we are overestimating the probability of occurrence of each genus
  • What sampling depth should we use to draw the richness maps?
    • Bias is highest at intermediate levels of reads (10,000 reads)
    • Could potentially adjust this to compensate for bias
  • Observed data may underestimate presence, so complex