Exploring lemur olfactory communication via statistical analyses in R

Project Summary

Questions asked: Do males and females scent mark equally? Do lemurs scent mark equally in breeding and non-breeding seasons?

Themes and Categories
Paul Bendich

Graduate students: Lydia Greene and Kendra Smyth

Faculty instructor: Julie Teichroeb

Course: EVANTH 246: Sociobiology

Data set: The frequency of scent-marking behavior in the Coquerel’s sifaka

Dependent variable: scent-marking frequency

Potential explanatory variables: sex, season, age, group size, free ranging, amount of time observed, individual identity

  • Step 1: Visualizing data and testing for normalcy (histograms, dotcharts, box plots, Shapiro test)
  • Step 2: Choosing an appropriate distribution and test
  • Step 3: Applying the test in R (Wilcoxon tests and GLMMs)
  • Step 4: Interpreting results

Model <- glmmadmb(Scentmark ~ Sex + Season + Group.size + Age + FR + (1|Individual) + offset(log(Obs..Time)), data=data, family=”nbinom”, zeroInflation=TRUE)

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