[R] Mapping in R

[Kelsey Scheitlin]

Hi, I am looking for a specific mapping capability in R that I can't seem to find, but think exists. I would like to make a border of a map have alternating black and white squares instead of the common latitude and longitude grid.  (example: http://www.cccturtle.org/sat_maps/map0bw8.gif). If anyone knows if there is or is not a function capable if doing this could you please let me know? Thanks!

Kelsey