Search results
Results From The WOW.Com Content Network
A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. [1] The term is often applied to groups that share similar features known as homoplasies , which are explained as a result of convergent evolution .
In taxonomy, a group is polyphyletic if it consists of clades from multiple separate branches of the tree of life, not forming a complete clade. This classification is often due to phenotypes that have converged or reverted so as to appear to be the same but which have not been inherited from common ancestors.
Ratites (/ ˈ r æ t aɪ t s /) are a polyphyletic group consisting of all birds within the infraclass Palaeognathae that lack keels and cannot fly. [3] They are mostly large, long-necked, and long-legged, the exception being the kiwi, which is also the only nocturnal extant ratite. The understanding of relationships within the paleognath clade ...
Thelodonti ('feeble-teeth') are a group of small, extinct jawless fishes with distinctive scales instead of large plates of armour. There is much debate over whether the group of Palaeozoic fish known as the Thelodonti (formerly coelolepids [11]) represent a monophyletic grouping, or disparate stem groups to the major lines of jawless and jawed ...
The Thermoanaerobacterales is a polyphyletic order of bacteria placed within the polyphyletic class Clostridia, and encompassing four families: the Thermoanaerobacteraceae, the Thermodesulfobiaceae, the Thermoanaerobacterales Family III.
It is a polyphyletic group. [1] Subdivisions. Although invertebrate experts ... groups that are generally incorporated into Aschelminthes include: Gastrotricha;
On the broadest scale, definitions fall into two groups. Willi Hennig (1966:148) defined monophyly as groups based on synapomorphy (in contrast to paraphyletic groups, based on symplesiomorphy, and polyphyletic groups, based on convergence). Some authors have sought to define monophyly to include paraphyly as any two or more groups sharing a ...
Thallophytes (Thallophyta or Thallobionta) are a polyphyletic group of non-mobile organisms traditionally described as "thalloid plants", "relatively simple plants" or "lower plants". Stephan Endlicher , a 19th-century Austrian botanist , separated the vegetable kingdom into the thallophytes (algae, lichens, fungi) and the cormophytes ...