Speciation Through Hybridization May or May Not Involve a Change

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The Answer is Speciation through hybridization can involve a change in the chromosome number of the hybrids, a phenomenon known as polyploid speciation, or it may not involve a change in chromosome number, known as homoploid speciation.

Polyploid speciation occurs when two different species interbreed and produce offspring with an increased number of chromosomes. This can occur through the fusion of unreduced gametes or through the hybridization of two different species. The resulting polyploid offspring are reproductively isolated from their parent species, leading to the formation of a new species. An example of polyploid speciation is the formation of the plant species Tragopogon mirus and Tragopogon miscellus through hybridization between two different species of Tragopogon.

Homoploid speciation, on the other hand, occurs when two different species interbreed and produce offspring with the same number of chromosomes as the parent species. Despite the same chromosome number, the hybrid offspring may still be reproductively isolated from their parent species, leading to the formation of a new species. An example of homoploid speciation is the formation of the monkeyflower species Mimulus peregrinus through hybridization between two different species of Mimulus.

Both polyploid and homoploid speciation events have been documented through genetic and morphological analyses, as well as through observations of reproductive isolation and ecological divergence in the newly formed species. These documented speciation events provide evidence for the role of hybridization in driving the formation of new species.

Speciation Through Hybridization May or May Not Involve a Change

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