Abstract:
:Since its discovery in 1907, polyploidy has been recognized as an important phenomenon in vascular plants, and several lines of evidence indicate that most, if not all, plant species ultimately have a polyploid ancestry. However, previous estimates of the frequency of polyploid speciation suggest that the formation and establishment of neopolyploid species is rare. By combining information from the botanical community's vast cytogenetic and phylogenetic databases, we establish that 15% of angiosperm and 31% of fern speciation events are accompanied by ploidy increase. These frequency estimates are higher by a factor of four than earlier estimates and lead to a standing incidence of polyploid species within genera of 35% (n = 1,506). Despite this high incidence, we find no direct evidence that polyploid lines, once established, enjoy greater net species diversification. Thus, the widespread occurrence of polyploid taxa appears to result from the substantial contribution of polyploidy to cladogenesis, but not from subsequent increases in diversification rates of polyploid lines.
journal_name
Proc Natl Acad Sci U S Aauthors
Wood TE,Takebayashi N,Barker MS,Mayrose I,Greenspoon PB,Rieseberg LHdoi
10.1073/pnas.0811575106subject
Has Abstractpub_date
2009-08-18 00:00:00pages
13875-9issue
33eissn
0027-8424issn
1091-6490pii
0811575106journal_volume
106pub_type
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