Family (biology)

Last updated

The hierarchy of biological classification's eight major taxonomic ranks. An order contains one or more families. Intermediate minor rankings are not shown. Biological classification L Pengo vflip.svg DomainKingdomClassOrderFamily
The hierarchy of biological classification's eight major taxonomic ranks. An order contains one or more families. Intermediate minor rankings are not shown.

Family (Latin : familia, pl.: familiae) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. [1] A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family".

Contents

The delineation of what constitutes a family—or whether a described family should be acknowledged—is established and decided upon by active taxonomists. There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to a lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching a consensus over time.

Nomenclature

The naming of families is codified by various international bodies using the following suffixes:

Name changes at the family level are regulated by the codes of nomenclature. For botanical families, some traditional names like Palmae (Arecaceae), Cruciferae (Brassicaceae), and Leguminosae (Fabaceae) are conserved alongside their standardized -aceae forms due to their historical significance and widespread use in the literature. Family names are typically formed from the stem of a type genus within the family. In zoology, when a valid family name is based on a genus that is later found to be a junior synonym, the family name may be maintained for stability if it was established before 1960. In botany, some family names that were found to be junior synonyms have been conserved due to their widespread use in the scientific literature. [5]

The family-group in zoological nomenclature includes several ranks: superfamily (-oidea), family (-idae), subfamily (-inae), and tribe (-ini). Under the principle of coordination, a name established at any of these ranks can be moved to another rank while retaining its original authorship and date, requiring only a change in suffix to reflect its new rank. [5]

New family descriptions are relatively rare in taxonomy, occurring in fewer than one in a hundred taxonomic publications. Such descriptions typically result from either the discovery of organisms with unique combinations of characters that do not fit existing families, or from phylogenetic analyses that reveal the need for reclassification. [5]

History

The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called the seventy-six groups of plants he recognised in his tables families (familiae). The concept of rank at that time was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera, which is far from how the term is used today.

In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees, herbs, ferns, palms, and so on. Notably, he restricted the use of this term solely within the book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ).

The family concept in botany was further developed by the French botanists Antoine Laurent de Jussieu and Michel Adanson. Jussieu's 1789 Genera Plantarum divided plants into 100 'natural orders,' many of which correspond to modern plant families. However, the term 'family' did not become standardized in botanical usage until after the mid-nineteenth century. [5]

In zoology, the family as a rank intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods).

The standardization of zoological family names began in the early nineteenth century. A significant development came in 1813 when William Kirby introduced the -idae suffix for animal family names, derived from the Greek 'eidos' meaning 'resemblance' or 'like'. The adoption of this naming convention helped establish families as an important taxonomic rank. By the mid-1800s, many of Linnaeus's broad genera were being elevated to family status to accommodate the rapidly growing number of newly discovered species. [5]

In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and the Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family.

Uses

Families serve as valuable units for evolutionary, paleontological, and genetic studies due to their relatively greater stability compared to lower taxonomic levels like genera and species. [6] [7] Families play a significant practical role in biological education and research. They provide an efficient framework for teaching taxonomy, as they group organisms with general similarities while remaining specific enough to be useful for identification purposes. For example, in botany, learning the characteristics of major plant families helps students identify related species across different geographic regions, since families often have worldwide distribution patterns. In many groups of organisms, families serve as the primary level for taxonomic identification keys, making them particularly valuable for field guides and systematic work as they often represent readily recognizable groups of related organisms with shared characteristics. [5]

In ecological and biodiversity research, families frequently serve as the foundational level for identification in survey work and environmental studies. This is particularly useful because families often share life history traits or occupy similar ecological niches. Some families show strong correlations between their taxonomic grouping and ecological functions, though this relationship varies among different groups of organisms. [5]

The stability of family names has practical importance for applied biological work, though this stability faces ongoing challenges from new scientific findings. Modern molecular studies and phylogenetic analyses continue to refine the understanding of family relationships, sometimes leading to reclassification. The impact of these changes varies among different groups of organisms – while some families remain well-defined and easily recognizable, others require revision as new evidence emerges about evolutionary relationships. This balance between maintaining nomenclatural stability and incorporating new scientific discoveries remains an active area of taxonomic practice. [5]

See also

Related Research Articles

<span class="mw-page-title-main">Linnaean taxonomy</span> Rank based classification system for organisms

Linnaean taxonomy can mean either of two related concepts:

  1. The particular form of biological classification (taxonomy) set up by Carl Linnaeus, as set forth in his Systema Naturae (1735) and subsequent works. In the taxonomy of Linnaeus there are three kingdoms, divided into classes, and the classes divided into lower ranks in a hierarchical order.
  2. A term for rank-based classification of organisms, in general. That is, taxonomy in the traditional sense of the word: rank-based scientific classification. This term is especially used as opposed to cladistic systematics, which groups organisms into clades. It is attributed to Linnaeus, although he neither invented the concept of ranked classification nor gave it its present form. In fact, it does not have an exact present form, as "Linnaean taxonomy" as such does not really exist: it is a collective (abstracting) term for what actually are several separate fields, which use similar approaches.

In biology, taxonomy is the scientific study of naming, defining (circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a more inclusive group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain, kingdom, phylum, class, order, family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, as he developed a ranked system known as Linnaean taxonomy for categorizing organisms and binomial nomenclature for naming organisms.

<span class="mw-page-title-main">Genus</span> Taxonomic rank directly above species and directly below family

Genus is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus.

<span class="mw-page-title-main">Binomial nomenclature</span> Species naming system

In taxonomy, binomial nomenclature, also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages. Such a name is called a binomial name, a binomen, binominal name, or a scientific name; more informally it is also historically called a Latin name. In the International Code of Zoological Nomenclature (ICZN), the system is also called binominal nomenclature, with an "n" before the "al" in "binominal", which is not a typographic error, meaning "two-name naming system".

<span class="mw-page-title-main">Order (biology)</span> Taxonomic rank between class and family

Order is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families.

Division is a taxonomic rank in biological classification that is used differently in zoology and in botany.

<span class="mw-page-title-main">Taxon</span> Grouping of biological populations

In biology, a taxon is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion, especially in the context of rank-based ("Linnaean") nomenclature. If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping.

<span class="mw-page-title-main">Tribe (biology)</span> Taxonomic rank between family and genus

In biology, a tribe is a taxonomic rank above genus, but below family and subfamily. It is sometimes subdivided into subtribes. By convention, all taxa ranked above species are capitalized, including both tribe and subtribe.

<span class="mw-page-title-main">Type genus</span> Term in biological taxonomy

In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name.

<span class="mw-page-title-main">Botanical name</span> Scientific name for a plant, alga or fungus

A botanical name is a formal scientific name conforming to the International Code of Nomenclature for algae, fungi, and plants (ICN) and, if it concerns a plant cultigen, the additional cultivar or Group epithets must conform to the International Code of Nomenclature for Cultivated Plants (ICNCP). The code of nomenclature covers "all organisms traditionally treated as algae, fungi, or plants, whether fossil or non-fossil, including blue-green algae (Cyanobacteria), chytrids, oomycetes, slime moulds and photosynthetic protists with their taxonomically related non-photosynthetic groups ."

<span class="mw-page-title-main">Pierre Magnol</span> French botanist

Pierre Magnol was a French botanist. He was born in the city of Montpellier, where he lived and worked for most of his life. He became Professor of Botany and Director of the Royal Botanic Garden of Montpellier and held a seat in the Académie Royale des Sciences de Paris for a short while. He was one of the innovators who devised the botanical scheme of classification. He was the first to publish the concept of plant families as they are understood today, a natural classification of groups of plants that have features in common.

Botanical nomenclature is the formal, scientific naming of plants. It is related to, but distinct from taxonomy. Plant taxonomy is concerned with grouping and classifying plants; botanical nomenclature then provides names for the results of this process. The starting point for modern botanical nomenclature is Linnaeus' Species Plantarum of 1753. Botanical nomenclature is governed by the International Code of Nomenclature for algae, fungi, and plants (ICN), which replaces the International Code of Botanical Nomenclature (ICBN). Fossil plants are also covered by the code of nomenclature.

Nomenclature codes or codes of nomenclature are the various rulebooks that govern the naming of living organisms. Standardizing the scientific names of biological organisms allows researchers to discuss findings.

In botanical nomenclature, a hybrid may be given a hybrid name, which is a special kind of botanical name, but there is no requirement that a hybrid name should be created for plants that are believed to be of hybrid origin. The International Code of Nomenclature for algae, fungi, and plants (ICNafp) provides the following options in dealing with a hybrid:

<span class="mw-page-title-main">History of plant systematics</span> Development of understanding of relationships among plants

The history of plant systematics—the biological classification of plants—stretches from the work of ancient Greek to modern evolutionary biologists. As a field of science, plant systematics came into being only slowly, early plant lore usually being treated as part of the study of medicine. Later, classification and description was driven by natural history and natural theology. Until the advent of the theory of evolution, nearly all classification was based on the scala naturae. The professionalization of botany in the 18th and 19th century marked a shift toward more holistic classification methods, eventually based on evolutionary relationships.

In botany, the phrase ordo naturalis, 'natural order', was once used for what today is a family. Its origins lie with Carl Linnaeus who used the phrase when he referred to natural groups of plants in his lesser-known work, particularly Philosophia Botanica. In his more famous works the Systema Naturae and the Species Plantarum, plants were arranged according to his artificial "Sexual system", and Linnaeus used the word ordo for an artificial unit. In those works, only genera and species were "real" taxa.

<span class="mw-page-title-main">Lilianae</span> Order of flowering plants

Lilianae is a botanical name for a superorder of flowering plants. Such a superorder of necessity includes the type family Liliaceae. Terminations at the rank of superorder are not standardized by the International Code of Nomenclature for algae, fungi, and plants (ICN), although the suffix -anae has been proposed.

Phylogenetic nomenclature is a method of nomenclature for taxa in biology that uses phylogenetic definitions for taxon names as explained below. This contrasts with the traditional method, by which taxon names are defined by a type, which can be a specimen or a taxon of lower rank, and a description in words. Phylogenetic nomenclature is regulated currently by the International Code of Phylogenetic Nomenclature (PhyloCode).

<span class="mw-page-title-main">Taxonomic rank</span> Level in a taxonomic hierarchy

In biology, taxonomic rank is the relative or absolute level of a group of organisms in a hierarchy that reflects evolutionary relationships. Thus, the most inclusive clades have the highest ranks, whereas the least inclusive ones have the lowest ranks. Ranks can be either relative and be denoted by an indented taxonomy in which the level of indentation reflects the rank, or absolute, in which various terms, such as species, genus, family, order, class, phylum, kingdom, and domain designate rank. This page emphasizes absolute ranks and the rank-based codes require them. However, absolute ranks are not required in all nomenclatural systems for taxonomists; for instance, the PhyloCode, the code of phylogenetic nomenclature, does not require absolute ranks.

<span class="mw-page-title-main">Glossary of scientific naming</span>

This is a list of terms and symbols used in scientific names for organisms, and in describing the names. For proper parts of the names themselves, see List of Latin and Greek words commonly used in systematic names. Note that many of the abbreviations are used with or without a stop.

References

  1. ↑ "Taxonomy - Definition, Classification & Example". Biology Dictionary. 19 March 2017. Retrieved 10 October 2022.
  2. ↑ Barnhart JH (15 January 1895). "Family Nomenclature". Bulletin of the Torrey Botanical Club. 22 (1): 1–25. doi:10.2307/2485402. JSTOR   2485402.
  3. ↑ ICN 2012, Section 2. Names of families and subfamilies, tribes and subtribes Article 18.
  4. ↑ International Commission on Zoological Nomenclature (1999). "Article 29.2. Suffixes for family-group names". International Code of Zoological Nomenclature (Fourth ed.). International Trust for Zoological Nomenclature, XXIX. p. 306. Archived from the original on 9 November 2004.
  5. 1 2 3 4 5 6 7 8 Winston, Judith E. (1999). "Description of Higher Taxa". Describing Species: Practical Taxonomic Procedure for Biologists. New York: Columbia University Press. pp. 383–394. ISBN   978-0-231-06824-6.
  6. ↑ Sahney S, Benton MJ, Ferry PA (August 2010). "Links between global taxonomic diversity, ecological diversity and the expansion of vertebrates on land". Biology Letters. 6 (4): 544–547. doi:10.1098/rsbl.2009.1024. PMC   2936204 . PMID   20106856.
  7. ↑ Sahney S, Benton MJ (April 2008). "Recovery from the most profound mass extinction of all time". Proceedings. Biological Sciences. 275 (1636): 759–765. doi:10.1098/rspb.2007.1370. PMC   2596898 . PMID   18198148.

Bibliography

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.