title: What can local and geographic population limits tell us about distributions?
abstract: OBJECTIVE
  Understanding the evolutionary and ecological factors that determine plant distributions is of primary importance in botanical research. These factors may vary in predictable ways across different spatial scales, and thus, we can leverage scale to reveal the underlying processes limiting plant distributions.
  
  
  METHODS
  We review various research considerations across local and geographic scales, including the investigation of dispersal and habitat limitation, evolutionary factors, abiotic and biotic factors, and research logistics. We also present two case studies, slender monkeyflower (Mimulus leptaleus) and cut-leaf monkeyflower (Mimulus laciniatus), in the California Sierra Nevada.
  
  
  RESULTS
  At a local spatial scale (within 50 m), no seeds were produced from plants sown at sites located just beyond known patches of M. leptaleus, but within the species' geographic range. At a much broader spatial scale (kilometers), at the highest and lowest elevations of the species' range, we found greatly reduced abundance and fecundity in plants sown outside of the geographic range limits of M. laciniatus.
  
  
  CONCLUSIONS
  These cases illustrate two contrasting spatial scales, yet agree in their illustration of strong habitat limitation. We end by discussing future avenues of research and by suggesting ways botanical researchers can frame their studies to maximize information gained on species requirements, distribution limits, and conservation among varying spatial scales.
authors.affiliation: School of Natural Sciences, 5200 North Lake Road, University of California, Merced, California 95343 USA jsexton2@ucmerced.edu.
authors.forename: Jason P
authors.initials: JP
authors.lastname: Sexton
authors.affiliation: School of Natural Sciences, 5200 North Lake Road, University of California, Merced, California 95343 USA.
authors.forename: Erin E
authors.initials: EE
authors.lastname: Dickman
mesh_terms: D005075:Biological Evolution; D002140:California; D002980:Climate; D017753:Ecosystem; D004777:Environment; D005843:Geography; D032241:Mimulus / Q000502:physiology*; D063148:Plant Dispersal
keywords: Mimulus; Sierra Nevada; dispersal limitation; evolution; habitat limitation; monkeyflowers; plant distribution; range limits; restoration; spatial scale