interspecific hybridization and introgression, allopolyploidy
, a mixture
Besides, the recent discovery of allopolyploidy
in 2 rodent species belonging to Octodontidae (Gallardo et al.
were found, then the putative parental taxa could be determined and the evolutionary origin of polyploid P.
Soltis & Soltis included under the name of hybrid speciation two phenomena: the homoploid hybrid speciation (what we have called hybrid, the result of the crossing between two different species resulting in another organism that maintains the same ploidy level as its parentals) and allopolyploidy
(even autopolyploidy when considering that autopolyploidy may typically involve hybridization between populations of the same species) (Soltis & Soltis 2009).
Although our sampling is less dense in Navarretia compared to Collomia, these results indicate that allopolyploidy
has occurred multiple times within the vernal pool clade, which makes discerning the timing of alloplolyploidization in N.
Three primary conditions are conducive to the development of allopolyploidy
: (1) the ability to form viable interspecific hybrids; (2) the ability to reproduce asexually, so that a hybrid might propagate, and the rare events of non-disjunction might have increased chances of occurring; and (3) the production of unreduced gametes.
This outcome of hybridization, which has also been suggested for allopolyploidy
(Stebbins 1950; Levin 1983), may have macroevolutionary consequences that deserve exploration with the growing array of molecular techniques.
Heilborn (cited in Davies, 1956) held that the seeming lack of allopolyploidy
in Carex might be attributable at least in part to this phenomenon, as the degeneration of all but one nucleus per PMC "prevents the formation of unreduced pollen dyads in any interspecific hybrid" (Davies, 1956: 351).
These are considered to have originated through allopolyploidy
(Norrmann, 1985, 1999 and in press), because their members share variants of a basic set of three genomes, one of which has been related to the genome of A.
From the early fifties through the seventies chromosome engineering using allopolyploidy
and anueploidy was akin to the biotechnology of today.
Phylogenetic relationships within Lithophragma (Saxifragaceae): Hybridization, allopolyploidy
, and ovary diversification.