The role of land bridges, ancient environments, and migrations in the assembly of the North American flora

  title={The role of land bridges, ancient environments, and migrations in the assembly of the North American flora},
  author={Alan Graham},
  journal={Journal of Systematics and Evolution},
  • A. Graham
  • Published 5 March 2018
  • Environmental Science
  • Journal of Systematics and Evolution
Continental‐scale assembly of floras results from past and present in situ diversification in association with several external processes. Among these processes are the making and breaking of connections among landmasses. Connections among landmasses are constantly in flux as are the climates and landscapes along the connection corridors, so that these corridors, or land bridges, may either facilitate or restrict migration at a given time. Across land bridges, changing landscape‐level and… 

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