| Abstract Detail
Chromosome and Karyotype Evolution in Plants Majure, Lucas [1]. Ploidal variation in Cactaceae: use of chromosomal data for understanding species complexes and resolving complicated evolutionary histories. Cactaceae are a major American radiation of around 1755 species, occupying a range of habitats from Canada to Patagonia. Although relatively young, presumably originating in the Oligocene, based on best estimates, the generation of the bulk of the diversity in the clade is much younger, having occurred during the Mio-, Plio- or Pleistocene. Base chromosome number is constant across the family (n=11), and although we lack comprehensive data, it appears that most major clades are majority diploid. However, numerous subclades are renown for whole genome duplication (e.g., Opuntioideae), this having been recorded as both auto- and allopolyploidy. Furthermore, hybridization is common in some of these subclades and may underpin, at least in part, the generation of this broadscale polyploidization. Without a basic understanding of chromosome number, however, much of this complexity may often be poorly characterized or even misinterpreted. I will dissect several polyploid complexes in Cactaceae and employ phylogenetic, morphological and other data types to illuminate the complicated evolutionary history of these groups. Although oftentimes increasingly difficult to quantify and delimit using morphological data alone, it is apparent given what we know about chromosome number and evolutionary history, that perhaps our current diversity estimates in Cactaceae are lower than they should be, given that cryptic species are very likely more common than has been previously recognized. Moving forward, careful chromosomal, morphological and phylogenetic work is needed across species complexes to be able to tease apart this fascinating part of the tree of life and to more fully reflect biological reality.
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Related Links:
Majure Lab Website
1 - Florida Museum Of Natural History, Department Of Natural History, 1659 Museum Rd. , Gainesville, FL, 32611, United States
Keywords:
polyploidy
Reticulate Evolution
Unreduced gametes
species complex.
Presentation Type: Colloquium Presentations
Session: C11, Chromosome and Karyotype Evolution in Plants
Location: /
Date: Friday, July 23rd, 2021
Time: 11:00 AM(EDT)
Number: C11005
Abstract ID:351
Candidate for Awards:None |
