In biological classification, class (Latin: classis) is a taxonomic rank, as well as a taxonomic unit, a taxon, in that rank.[a] Other well-known ranks in descending order of size are life, domain, kingdom, phylum, order, family, genus, and species, with class fitting between phylum and order. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the prefix sub-: subclass (Latin: subclassis). For example, dogs are in the class Mammalia.
The composition of each class is determined by a taxonomist. Often there is no exact agreement, with different taxonomists taking different positions. There are no hard rules that a taxonomist needs to follow in describing a class, but for well-known animals there is likely to be consensus.
In botany, classes are now rarely discussed. Since the first publication of the APG system in 1998, which proposed a taxonomy of the flowering plants up to the level of orders, many sources have preferred to treat ranks higher than orders as informal clades. Where formal ranks have been assigned, the ranks have been reduced to a very much lower level, e.g. class Equisitopsida for the land plants, with the major divisions within the class assigned to subclasses and superorders.
For some clades, a number of alternative classifications are used.
|Name||Meaning of prefix||Example 1||Example 2||Example 3|
|Parvclass||parvus: small, unimportant||Neornithes|
The class as a distinct rank of biological classification having its own distinctive name (and not just called a top-level genus (genus summum)) was first introduced by the French botanist Joseph Pitton de Tournefort in his classification of plants that appeared in his Eléments de botanique, 1694.
In the first edition of his Systema Naturae (1735). Carl Linnaeus divided all three of his kingdoms of Nature (minerals, plants, and animals) into classes. Only in the animal kingdom are Linnaeus's classes similar to the classes used today; his classes and orders of plants were never intended to represent natural groups, but rather to provide a convenient "artificial key" according to his Systema Sexuale, largely based on the arrangement of flowers.
Charophyceae is a class (biology) of charophyte green algae, and consist of the single order Charales, commonly known as "stoneworts" and "brittleworts". It is a basal Phragmoplastophyta clade as sister of another unnamed clade which contains the Embryophytes (land plants). Charophyceae are a class within the Streptophyta. Current consensus treats Charophyceae as a class under division Charophyta, with Chlorophyta remaining a distinct division. In 2018, the first nuclear genome sequence from a species belonging to the most basal branch within the Phragmoplastophyta, the Charophyceae, has been published: that of Chara brauniiMany of the complex traits related to sexual reproduction, photosynthesis, and other defining characteristics of plants evolved first in Streptophytes; analysis of cpDNA (chloroplast DNA), for instance, reveals that many characteristics of plant chloroplasts evolved first in the Streptophyte genera Staurastrum and Zygnema.Cordyline fruticosa
Cordyline fruticosa is an evergreen flowering plant in the Asparagus family (Asparagaceae). The plant is of great cultural importance to the traditional animistic religions of Austronesian and Papuan peoples of the Pacific Islands, New Zealand, Island Southeast Asia, and Papua New Guinea. It is also cultivated for food, traditional medicine, and as an ornamental for its variously colored leaves. It is identified by a wide variety of common names, including ti plant, palm lily, cabbage palm, and good luck plant.Domesticated plants and animals of Austronesia
One of the major human migration events was the maritime settlement of the islands of the Indo-Pacific by the Austronesian peoples, believed to have started from at least 5,500 to 4,000 BP (3500 to 2000 BC). These migrations were accompanied by a set of domesticated, semi-domesticated, and commensal plants and animals transported via outrigger ships and catamarans that enabled early Austronesians to thrive in the islands of Maritime Southeast Asia, Near Oceania (Melanesia), and Remote Oceania (Micronesia and Polynesia), Madagascar, and the Comoros Islands.They include crops and animals believed to have originated from the Hemudu and Majiabang cultures in the hypothetical proto-Austronesian homelands in mainland China, as well as other plants and animals believed to have been first domesticated from within Taiwan, Island Southeast Asia, and New Guinea. Some of these plants are sometimes also known as "canoe plants", especially in the context of the Polynesian migrations. Domesticated animals and plants introduced during historic times are not included.Fetal bovine serum
Fetal bovine serum (FBS) comes from the blood drawn from a bovine fetus via a closed system of collection at the slaughterhouse. Fetal bovine serum is the most widely used serum-supplement for the in vitro cell culture of eukaryotic cells. This is due to it having a very low level of antibodies and containing more growth factors, allowing for versatility in many different cell culture applications.
The globular protein, bovine serum albumin (BSA), is a major component of fetal bovine serum. The rich variety of proteins in fetal bovine serum maintains cultured cells in a medium in which they can survive, grow, and divide.
FBS is not a fully defined media component, and as such may vary in composition between batches. As a result, serum free and chemically defined media (CDM) have been developed as a matter of good laboratory practice.Guhanagari A Book on Urban Wildlife
Guhanagari: A Book on Urban Wildlife is an attempt to show the diversity of life in Christ University, Bangalore. The book documents from the migratory fluttering butterflies to mammals living inside the 25 acre university campus.The work was done, while they were students of Christ University, Bangalore campus.Istanbul High School
İstanbul High School, (Turkish: İstanbul Lisesi, German: Istanbuler Gymnasium) also commonly known as İstanbul Erkek Lisesi, abbreviated İEL, is one of the oldest and internationally renowned high schools of Turkey. The school is considered elite among Turkish public high schools. Germany recognizes the school as a Deutsche Auslandsschule (German International school).
İstanbul Lisesi is located in Cağaloğlu, İstanbul. The school has changed several buildings throughout its history. Since 1933 the school has used its current building. The building was designed by architects Alexander Vallaury and Raimondo D'Aronco and inaugurated in 1882 as the Düyun-u Umumiye (Council of Ottoman Revenues and Debts Administration) Building, which overlooks the entrance to the Bosphorus and the Golden Horn. A new building adjacent to the main historical building was inaugurated in 1984, providing new boarding and sports facilities. The primary languages of instruction are Turkish and German. The secondary foreign language of instruction is English.Pink whipray
The pink whipray (Himantura fai) is a species of stingray in the family Dasyatidae, with a wide but ill-defined distribution in the tropical Indo-Pacific from southern Africa to Polynesia. It is a bottom dweller that generally inhabits shallow water under 70 m (230 ft) deep, in sandy areas associated with coral reefs. Individuals exhibit a high degree of fidelity to particular locations. The pink whipray has a diamond-shaped pectoral fin disc wider than long, with a broad-angled snout and a very long, whip-like tail without fin folds. It has only a few small thorns on its back and is uniform brownish to grayish pink in color, becoming much darker past the tail sting. This large ray can reach 1.8 m (5.9 ft) across and over 5 m (16 ft) long.
Gregarious in nature, the pink whipray has been known to form large active and resting aggregations, and associate with other large ray species. It preys mainly on prawns, but also consumes other benthic invertebrates and bony fishes. This species is aplacental viviparous, in which the unborn young are nourished by histotroph ("uterine milk") produced by the mother. Across much of its range, substantial numbers of pink whiprays are caught incidentally by a variety of fishing gear and marketed for meat, skin, and cartilage. It is also of importance to ecotourism, being attracted to visitors with bait. The International Union for Conservation of Nature (IUCN) has listed this species under Least Concern, due to its wide distribution that includes relatively protected areas, such as northern Australia. However, its population in Southeast Asia is likely declining under heavy fishing pressure, and there it has been assessed as Vulnerable.Schauenberg's index
Schauenberg's index is the ratio of skull length to cranial capacity.
This index was introduced by Paul Schauenberg in 1969 as a method to identify European wildcat (Felis silvestris) skulls and distinguish them from domestic cat (Felis catus) skulls.