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in taxonomy: see classificationclassification,
in biology, the systematic categorization of organisms into a coherent scheme. The original purpose of biological classification, or systematics, was to organize the vast number of known plants and animals into categories that could be named, remembered, and
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(also type), the highest taxonomic category in the classification of animals. A phylum, or type, is made up of related classes. The term “type” was proposed in 1825 by H. de Blain-ville, who applied it to the four “branches” of animals distinguished by G. Cuvier in 1812.

Phyla vary in size: for example, the phylum Porifera comprises approximately 5,000 species, whereas the phylum Pogonophora has only about 100 species. Phyla are frequently divided into sub-phyla. For example, the phylum Chordata has four sub-phyla—Cephalochordata, Tunicata, Acrania, and Vertebrata. Organisms belonging to the same phylum are marked by the same structural organization. The number of phyla and their size vary from one classification system to another. Some taxonomists recognize as few as ten phyla, and others as many as 33. However, these differences do not diminish the importance of phyla as categories that reflect the principal branches of the phylogenetic tree of the animal kingdom.

In plant classification, which has been worked out independently from animal classification, the taxonomic category corresponding to a phylum is called a division.



A major taxonomic category in classifying animals (and plants in some systems), composed of groups of related classes.


a major taxonomic division of living organisms that contain one or more classes. An example is the phylum Arthropoda (insects, crustaceans, arachnids, etc., and myriapods)
References in periodicals archive ?
Phylum 2 Spirochaetae (Spirochetes, Corkscrew Bacteria with Internal Flagella)
Phylum Bryozoa/Ectoprocta & Endoprocta (Moss animals)
As we know, the phylum Firmicutes is the dominant phyla of intestinal microbiota in healthy people.
In 2013 in the Proceedings of the National Academy of Sciences, McLean and colleagues were the first to describe a member of another uncultivated phylum, TM6.
1]), dominado por especies del phylum Cryptophyta, cuyas especies mas abundantes fueron C.
It's really exciting and a big breakthrough that tells us what to look for and how we, too, might be able to communicate with this entire phylum of animals," he added.
1999), and therefore our phylogenetic analysis was geared toward including representatives of each phylum collected.
The taxonomic location of the phylum Onychophora, also know as "velvet worms", has been controversial because of its phenotypic and genotypic characteristics that are related to both annelids and arthropods, making it difficult to locate this phylum within the zoological scale (Hickman et al.
The organisms in the phylum Arthropoda, which includes insects, spiders, and lobsters, account for more than 90 percent of all the animal species on Earth.
Integrins are a widely expressed family of cell surface adhesion receptors whose existence in sponges, the oldest extant Metazoan phylum, has been clearly established.
In the head-to-head battles, one phylum or type of Pokemon, say water, will do better against certain opposing types, such as fire, in a complex version of the old rock-paper-scissors game.