American Amphitropical Disjunction
Working Group
(see figshare site for data and comments)

Our Goal:

To promote and facilitate collaborative research and communication of data and ideas for the study of organisms with an American amphitropical disjunct distribution, occurring in areas of North and South America on either side of the neotropics.


1) To maintain and continually update a database of AAD examples, with referenced information on their biogeographic history (including the timing, direction, and mechanism of dispersal), ecology, genetics (including chromosome number), morphology, nomenclature, phylogeny, reproductive biology, and speciation rates;

2) To maintain an annotated bibliography of papers pertinent to the study of AADs;generate robust phylogenies of AAD distributed plant group;

3) To provide an active forum for discussion of AAD organisms;

4) To provide distribution maps of AAD examples;

5) To evaluate common patterns and processes among AAD organisms that may be used to generate hypotheses on aspects of their dispersal and diversification.


Global flyways: a synthesis of bird migration research
21–22 Nov 2023

Lists of Amphitropically Distributed Vascular Plants, after:
Simpson, M. G., L. A. Johnson, T. Villaverde, and C. M. Guilliams. 2017. American Amphitropical Disjuncts: Perspectives from vascular plant analyses and prospects for future research. American Journal of Botany 104: 1600-1650. (pdf)

Bipolar AAD Plants

Desert AAD Plants

Temperate AAD Plants

Rejected Plants considered AAD in past works

For spreadsheet of data, see: