Challenges:

Determine the species richness for a group of interest (plants, herps, birds, mammals - whichever group has enough occurrence records to be meaningful) in Western North America, at multiple grid sizes (from .1 to 1 degree latitudexlongitude cell(s).  What is the observed overall richness?  What are the estimates of richness from DIVA or EstimateS? Is the estimated richness significantly different from observed richness?  What does this mean to you?  Do the values from different estimators give similar results?  Why or why not, based on number of singletons, doubletons, infrequents, rares, etc... Is there an association between bird species richness with any abiotic factor, like topographic index, anthropogenic biomes (http://www.ecotope.org/files/anthromes/anthromes_v1.zip), land-cover, mean annual temperature or precipitation, or any other of the multiple climatic variables?  Test this question utilizing straight regressions but also perform spatial autocorrelation analyses to determine amounts of spatial autocorrelation (Moran's I) as well as test that take into account amount of spatial autocorrelation in testing for association between variables.  Is there a "significant" relationship between, say, mean annual temperature and species richness, simply because of cospatial autocorrelations?

Perform the same set of analyses above just for Colorado.  Compare Colorado results to those from all of Western North America.

Focus on the question along the Front Range, assessing richness along the elevational gradient from the end of the Plains all the way up to the Continental Divide.  Can you account for declining area along the gradient?  What are the patterns along the elevational gradient?  Do you find a mid-elevation "hump" in diversity for the group in question?

Perform a similar set of analyses to the ones above in Austria.  Note that the Alps effectively run from East to West through the southern and central part of Austria, as opposed to running in the North to South direction like the Rockies or Sierras in the western North America. Determine the overall species richness of a higher level taxon of interest in Austria and then just focus on the Alps.  Compare and contrast your findings in Austria with those from North America.  What are some explanations, historical and current, for the differences you find?