Error(s) in re-building vignettes:
  ...
--- re-building 'DrawingPhylogenies.Rnw' using Sweave
Error: processing vignette 'DrawingPhylogenies.Rnw' failed with diagnostics:
Running 'texi2dvi' on 'DrawingPhylogenies.tex' failed.
LaTeX errors:
! Package xcolor Error: Undefined color `darkblue'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
 ...                                              
! Emergency stop.
 ...                                              
                                                  
l.14 \maketitle
               
!  ==> Fatal error occurred, no output PDF file produced!
--- failed re-building 'DrawingPhylogenies.Rnw'

--- re-building 'MoranI.Rnw' using Sweave
Error: processing vignette 'MoranI.Rnw' failed with diagnostics:
Running 'texi2dvi' on 'MoranI.tex' failed.
LaTeX errors:
! Package xcolor Error: Undefined color `darkblue'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
 ...                                              
! Emergency stop.
 ...                                              
                                                  
l.17 \maketitle
               
!  ==> Fatal error occurred, no output PDF file produced!
--- failed re-building 'MoranI.Rnw'

--- re-building 'RandomTopologies.Rnw' using Sweave
Error: processing vignette 'RandomTopologies.Rnw' failed with diagnostics:
Running 'texi2dvi' on 'RandomTopologies.tex' failed.
LaTeX errors:
! Package xcolor Error: Undefined color `darkblue'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
 ...                                              
! Emergency stop.
 ...                                              
                                                  
l.13 \maketitle
               
!  ==> Fatal error occurred, no output PDF file produced!
--- failed re-building 'RandomTopologies.Rnw'

SUMMARY: processing the following files failed:
  'DrawingPhylogenies.Rnw' 'MoranI.Rnw' 'RandomTopologies.Rnw'

Error: Vignette re-building failed.
Execution halted