Abstract Detail

Reticulate evolution and biogeography in ferns and lycophytes - a colloquium honoring Dr. David Barrington

Southgate, Morgan [1], Barrington, David [2], Patel, Nikisha R [3].

Ecological outcome of allopolyploidy in Adiantum (Pteridaceae): niche intermediacy and expansion into novel habitats.

In northeastern North America, the Adiantum pedatum complex provides the opportunity to characterize the ecological outcome of allopolyploidy in the ferns. Adiantum viridimontanum (Green Mountain maidenhair fern) is an allotetraploid hybrid derived from a sterile cross between the serpentine-restricted diploid species A. aleuticum (Aleutian maidenhair fern) and the rich-woods diploid species A. pedatum (northern maidenhair fern). Here, we characterized the ecological niche of the allotetraploid hybrid relative to the niches of its two progenitors by establishing 48 survey plots at 13 sites where the three species occur in Vermont. At each survey plot, we gathered data concerning the habitat type, light availability, topography, and substrate characteristics, and collected a soil sample for analysis of chemical composition. This yielded a set of 32 quantitative ecological variables, which were analyzed using principal component analysis (PCA) to characterize the multivariate ecological niche of each species as circumscribed by the position of survey plots in environmental space. Along the first principal component, the ecological niche of the allotetraploid appeared between those of its progenitors in environmental space, closely overlapping the niche of A. aleuticum and slightly overlapping that of A. pedatum. Along the second principal component, a portion of the ecological niche of the allotetraploid was transgressive relative to the niches of its progenitors in environmental space; in geographic space, these survey plots correspond to northern hardwood serpentine-influenced forests, a habitat type that is novel for the species complex. Thus, the ecological outcome of allopolyploid speciation in the A. pedatum complex appears to include elements of both niche intermediacy and niche expansion into novel habitats.

1 - University of Vermont, Plant Biology, 111 Jeffords Hall, 63 Carrigan Drive, Burlington, VT, 05405, USA
2 - University Of Vermont, Plant Biology, 111 Jeffords Hall, 63 Carrigan Drive, Burlington, VT, 05405, United States
3 - University of Connecticut, Ecology and Evolutionary Biology, 75 North Eagleville Rd, Storrs, Connecticut, 06269, United States

Keywords:
allopolyploidy
niche intermediacy
niche expansion
Adiantum viridimontanum
serpentine.

Presentation Type: Colloquium Presentations
Session: CO09, Reticulate evolution and biogeography in ferns and lycophytes - a colloquium honoring Dr. David Barrington
Location: San Luis 2/Starr Pass
Date: Tuesday, July 30th, 2019
Time: 2:30 PM
Number: CO09005
Abstract ID:547
Candidate for Awards:Edgar T. Wherry award