A demo showing how to use publicly available presence-absence data (in a .dbf) to create beautiful spatial maps using R
These data indicate the presence or absence of mosquito species within counties of New Jersey. I pulled these data from maps published on the Rutgers Center of Vector Biology (http://www.rci.rutgers.edu/~vbcenter/mosquitospeciesdistributionsNJ.pdf). According to that source, these distributions come from county mosquito species lists, light trap data in statewide program, pools submitted to PHEL for arboviral testing and some literature records as of 2012. I do not claim that these data are complete or accurate, but I am using them to illustrate how presence-absence data can be used to map distributions.