d-novl is a Monte Carlo program designed to generate a null expectation of overlap between two niche-based distribution models. The user may choose between two growth algorithms: the separated algorithm grows a random number of disjointed growth areas, whereas the number of islands algorithm allows the user to input the desired number of growth areas. The latter algorithm can also be used to grow a single growth area. The resulting probability distribution of expected overlap values can be exported into a spreadsheet for further analysis.
d-novl is freely available for Mac and Windows platforms at http://www.mygalomorphae.org.