Paraphyletic groups omit some descendants; polyphyletic groups lack the most recent common ancestor.
Paraphyletic example: reptiles (excluding birds); polyphyletic example: 'warm-blooded animals' (birds and mammals evolved endothermy independently), or 'flying vertebrates'. Such groups are avoided in cladistics.
Paraphyletic groups are often defined by ancestral traits. Polyphyletic groups result from convergence.
Common mistake: assuming familiar groups are always natural.
Paraphyletic groups omit some descendants; polyphyletic groups lack the most recent common ancestor.
Paraphyletic and Polyphyletic is one of the 52 topics in Taxonomy & Biodiversity. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Shared Derived Characters, Monophyletic Groups, Phylogenetic Classification.
Fish excluding tetrapods is paraphyletic.
Work through the Beginner topics in Taxonomy & Biodiversity first, such as Taxonomy, Binomial Nomenclature, Taxonomic Hierarchy, then return to Paraphyletic and Polyphyletic. Intermediate topics assume the Beginner vocabulary.
The closest topics to Paraphyletic and Polyphyletic are Shared Derived Characters, Monophyletic Groups, Phylogenetic Classification, Invasive Species. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Paraphyletic and Polyphyletic. To practise the whole of Taxonomy & Biodiversity, use the Taxonomy & Biodiversity quiz.
Paraphyletic and Polyphyletic: Paraphyletic groups omit some descendants; polyphyletic groups lack the most recent common ancestor. Shared Derived Characters: Novel traits inherited from a recent common ancestor that define a clade. Read both side by side and note what each one explains.
Assuming familiar groups are always natural.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Shared Derived Characters and explain the difference aloud. Finally, take the Taxonomy & Biodiversity quiz and come back to this page for any question you miss.
Novel traits inherited from a recent common ancestor that define a clade.
🗂️ Taxonomy & BiodiversityA group containing an ancestor and all of its descendants, called a clade.
🗂️ Taxonomy & BiodiversityGroups organisms by evolutionary relationships so that taxa reflect common ancestry.
🗂️ Taxonomy & BiodiversityNon-native organisms that spread and harm local ecosystems and economies.
🗂️ Taxonomy & Biodiversity