Editing Polyphyly (section)

== Polyphyletic species ==
[[Species]] have a special status in systematics as being an observable feature of nature itself and as the basic unit of classification.<ref>{{cite journal|last1=Queiroz|first1=Kevin|last2=Donoghue|first2=Michael J.|title=Phylogenetic Systematics and the Species Problem|journal=Cladistics|date=December 1988|volume=4|issue=4|pages=317–338|doi=10.1111/j.1096-0031.1988.tb00518.x|pmid=34949064 |s2cid=40799805}}</ref> It is usually implicitly assumed that species are monophyletic (or at least [[paraphyletic]]). However, [[hybrid speciation]] arguably leads to polyphyletic species.<ref>{{Cite journal|last1=Hörandl |first1=E. |last2=Stuessy |first2=T.F.|title=Paraphyletic groups as natural units of biological classification|journal=Taxon|date=2010|volume=59|issue=6|pages=1641–1653|doi=10.1002/tax.596001 |bibcode=2010Taxon..59.1641H }}</ref> Hybrid species are a common phenomenon in nature, particularly in plants where [[polyploidy]] allows for rapid speciation.<ref>{{cite journal|last=Linder|first=C.R.|author2=Risenberg, L.H.|title=Reconstructing patterns of reticulate evolution in plants|journal=American Journal of Botany|date=22 June 2004|volume=91|pages=1700–1708|issue=10|doi=10.3732/ajb.91.10.1700|pmid=18677414|pmc=2493047|bibcode=2004AmJB...91.1700L }}</ref> Some [[Cladistics|cladist]] authors do not consider species to possess the property of "-phyly", which they assert applies only to groups of species.<ref>{{Cite journal |last1=Nixon |first1=Kevin C. |last2=Wheeler |first2=Quentin D. |date=September 1990 |title=An amplification of the phylogenetic species concept |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1096-0031.1990.tb00541.x |journal=Cladistics |language=en |volume=6 |issue=3 |pages=211–223 |doi=10.1111/j.1096-0031.1990.tb00541.x |issn=0748-3007}}</ref><ref>{{Cite book |last1=Brower |first1=Andrew V. Z. |title=Biological systematics: principles and applications |last2=Schuh |first2=Randall T. |date=2021 |publisher=Comstock Publishing Associates, an imprint of Cornell University Press |isbn=978-1-5017-5277-3 |edition=3 |location=Ithaca, New York}}</ref>