ellipse: no visible global function definition for 'qchisq'
niche.par.plot: no visible global function definition for 'par'
niche.par.plot: no visible global function definition for 'density'
niche.par.plot: no visible global function definition for 'lines'
niche.plot: no visible global function definition for 'combn'
niche.plot: no visible global function definition for 'par'
niche.plot: no visible global function definition for 'plot.new'
niche.plot: no visible global function definition for 'plot.window'
niche.plot: no visible global function definition for 'density'
niche.plot: no visible global function definition for 'segments'
niche.plot: no visible global function definition for 'lines'
niche.plot: no visible global function definition for 'points'
niche.plot: no visible global function definition for 'box'
niche.plot: no visible global function definition for 'axis'
niche.plot: no visible global function definition for 'mtext'
niche.plot: no visible global function definition for 'legend'
overlap: no visible global function definition for 'qchisq'
overlap: no visible global function definition for 'rnorm'
overlap.plot : <anonymous>: no visible global function definition for
  'hist'
overlap.plot: no visible binding for global variable 'quantile'
overlap.plot: no visible global function definition for 'par'
overlap.plot: no visible global function definition for 'plot.new'
overlap.plot: no visible global function definition for 'plot.window'
overlap.plot: no visible global function definition for 'hist'
overlap.plot: no visible global function definition for 'abline'
overlap.plot: no visible global function definition for 'text'
overlap.plot: no visible global function definition for 'box'
overlap.plot: no visible global function definition for 'axis'
overlap.plot: no visible global function definition for 'mtext'
overlap.plot: no visible global function definition for 'legend'
rwish: no visible global function definition for 'rnorm'
rwish: no visible global function definition for 'rchisq'
Undefined global functions or variables:
  abline axis box combn density hist legend lines mtext par plot.new
  plot.window points qchisq quantile rchisq rnorm segments text
Consider adding
  importFrom("graphics", "abline", "axis", "box", "hist", "legend",
             "lines", "mtext", "par", "plot.new", "plot.window",
             "points", "segments", "text")
  importFrom("stats", "density", "qchisq", "quantile", "rchisq", "rnorm")
  importFrom("utils", "combn")
to your NAMESPACE file.