Species richness is greatest in the tropics, and much of this diversity is concentrated in mountains. Janzen proposed that reduced seasonal temperature variation selects for narrower thermal tolerances and limited dispersal along tropical elevation gradients [Janzen DH (1967)
- Publication Date:
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- Proceedings of the National Academy of Sciences
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- p. 12471-12476
- Proceedings of the National Academy of Sciences
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- National Science Foundation
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