27-490: Neoaves is a clade that consists of all modern birds (Neornithes or Aves) with the exception of Palaeognathae (ratites and kin) and Galloanserae (ducks, chickens and kin). This group is defined in the PhyloCode by George Sangster and colleagues in 2022 as "the most inclusive crown clade containing Passer domesticus , but not Gallus gallus ". Almost 95% of the roughly 10,000 known species of extant birds belong to
54-534: A clade (from Ancient Greek κλάδος (kládos) 'branch'), also known as a monophyletic group or natural group , is a grouping of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree . In the taxonomical literature, sometimes the Latin form cladus (plural cladi ) is used rather than the English form. Clades are
81-479: A "ladder", with supposedly more "advanced" organisms at the top. Taxonomists have increasingly worked to make the taxonomic system reflect evolution. When it comes to naming , this principle is not always compatible with the traditional rank-based nomenclature (in which only taxa associated with a rank can be named) because not enough ranks exist to name a long series of nested clades. For these and other reasons, phylogenetic nomenclature has been developed; it
108-623: A clade can be described based on two different reference points, crown age and stem age. The crown age of a clade refers to the age of the most recent common ancestor of all of the species in the clade. The stem age of a clade refers to the time that the ancestral lineage of the clade diverged from its sister clade. A clade's stem age is either the same as or older than its crown age. Ages of clades cannot be directly observed. They are inferred, either from stratigraphy of fossils , or from molecular clock estimates. Viruses , and particularly RNA viruses form clades. These are useful in tracking
135-532: A generally Mesozoic form taxon formerly believed to constitute the common ancestors of charadriiforms, waterfowl and flamingos . They are now assumed to be mostly basal taxa of the charadriiforms and/or "higher waterbirds", which probably were two distinct lineages 65 mya already, and few if any are still believed to be related to the well-distinct waterfowl. Taxa formerly considered graculavids are: Other wader- or gull-like birds incertae sedis , which may or may not be Charadriiformes, are: Shorebirds pursue
162-421: A larger diversity of parental care strategies than do most other avian orders. They therefore present an attractive set of examples to support the understanding of the evolution of parental care in avians generally. The ancestral avian most likely had a female parental care system. The shorebird ancestor specifically evolved from a bi-parental care system, yet the species within the clade Scolopacidae evolved from
189-497: A male parental care system. These transitions might have occurred for several reasons. Brooding density is correlated with male parental care. Male care systems in birds are shown to have a very low breeding density while female care systems in birds have a high breeding density. (Owens 2005). Certain rates of male and female mortality, male and female egg maturation rate, and egg death rate have been associated with particular systems as well. It has also been shown that sex role reversal
216-2215: A reduced hard polytomy of six clades within Passerea. Despite other disagreements, these studies do agree on a number of supraorderal groups, which Reddy and colleagues in 2017 dubbed the "magnificent seven", which together with three "orphaned orders" make up Neoaves. Significantly, they both include a large waterbird clade ( Aequornithes ) and a large landbird clade ( Telluraves ). The groups defined by Reddy and colleagues (2017) are as follows: Mirandornithes (flamingos, grebes) Columbimorphae (pigeons, mesites, sandgrouse) Otidimorphae (cuckoos, bustards, turacos) Strisores (hummingbirds, swifts, nightbirds) Opisthocomiformes (hoatzin) Gruiformes (cranes, rails) Charadriiformes (shorebirds) Eurypgimorphae (sunbittern, kagu, tropicbirds) Aequornithes (core waterbirds) Afroaves Australaves Strisores (hummingbirds, swifts, nightbirds) Columbimorphae (pigeons, mesites, sandgrouse) Otidimorphae (cuckoos, bustards, turacos) Gruiformes (cranes, rails) Mirandornithes (flamingoes, grebes) Charadriiformes (shorebirds) Eurypgimorphae (sunbittern, kagu, tropicbirds) Aequornithes (core waterbirds) Opisthocomiformes (hoatzin) Telluraves (core landbirds) Mirandornithes (flamingoes, grebes) Columbimorphae (pigeons, mesites, sandgrouse) Otidimorphae (cuckoos, bustards, turacos) Strisores (hummingbirds, swifts, nightbirds) Opisthocomiformes (hoatzin) Gruiformes (cranes, rails) Charadriiformes (shorebirds) Eurypgimorphae (sunbittern, kagu, tropicbirds) Aequornithes (core waterbirds) Afroaves Australaves Mirandornithes (flamingos, grebes) Columbimorphae (pigeons, mesites, sandgrouse) Otidimorphae (cuckoos, bustards) Musophagiformes (turacos) Gruiformes (cranes, rails) Aequornithes (core waterbirds) Charadriiformes (shorebirds) Opisthocomiformes (hoatzin) Strisores (hummingbirds, swifts, nightbirds) Eurypygimorphae (sunbittern, kagu, tropicbirds) Telluraves (core landbirds) Mirandornithes (flamingos, grebes) Clade In biological phylogenetics ,
243-422: A revised taxonomy based on a concept strongly resembling clades, although the term clade itself would not be coined until 1957 by his grandson, Julian Huxley . German biologist Emil Hans Willi Hennig (1913–1976) is considered to be the founder of cladistics . He proposed a classification system that represented repeated branchings of the family tree, as opposed to the previous systems, which put organisms on
270-429: A suffix added should be e.g. "dracohortian". A clade is by definition monophyletic , meaning that it contains one ancestor which can be an organism, a population, or a species and all its descendants. The ancestor can be known or unknown; any and all members of a clade can be extant or extinct. The science that tries to reconstruct phylogenetic trees and thus discover clades is called phylogenetics or cladistics ,
297-406: Is a diverse order of small to medium-large birds . It includes about 390 species and has members in all parts of the world. Most charadriiform birds live near water and eat invertebrates or other small animals; however, some are pelagic (seabirds), others frequent deserts, and a few are found in dense forest. Members of this group can also collectively be referred to as shorebirds . The order
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#1732773285574324-499: Is also used with a similar meaning in other fields besides biology, such as historical linguistics ; see Cladistics § In disciplines other than biology . The term "clade" was coined in 1957 by the biologist Julian Huxley to refer to the result of cladogenesis , the evolutionary splitting of a parent species into two distinct species, a concept Huxley borrowed from Bernhard Rensch . Many commonly named groups – rodents and insects , for example – are clades because, in each case,
351-476: Is in turn included in the mammal, vertebrate and animal clades. The idea of a clade did not exist in pre- Darwinian Linnaean taxonomy , which was based by necessity only on internal or external morphological similarities between organisms. Many of the better known animal groups in Linnaeus's original Systema Naturae (mostly vertebrate groups) do represent clades. The phenomenon of convergent evolution
378-601: Is probably due to convergent evolution brought about by semiaquatic habits. Specimen VI 9901 ( López de Bertodano Formation , Late Cretaceous of Vega Island , Antarctica) is probably a basal charadriiform somewhat reminiscent of a thick-knee . However, more complete remains of undisputed charadriiforms are known only from the mid- Paleogene onwards. Present-day orders emerged around the Eocene - Oligocene boundary, roughly 35-30 mya . Basal or unresolved charadriiforms are: The "transitional shorebirds" (" Graculavidae ") are
405-515: Is responsible for many cases of misleading similarities in the morphology of groups that evolved from different lineages. With the increasing realization in the first half of the 19th century that species had changed and split through the ages, classification increasingly came to be seen as branches on the evolutionary tree of life . The publication of Darwin's theory of evolution in 1859 gave this view increasing weight. In 1876 Thomas Henry Huxley , an early advocate of evolutionary theory, proposed
432-489: Is still controversial. As an example, see the full current classification of Anas platyrhynchos (the mallard duck) with 40 clades from Eukaryota down by following this Wikispecies link and clicking on "Expand". The name of a clade is conventionally a plural, where the singular refers to each member individually. A unique exception is the reptile clade Dracohors , which was made by haplology from Latin "draco" and "cohors", i.e. "the dragon cohort "; its form with
459-683: The Charadriiformes are an ancient group is also borne out by the fossil record. Alongside the Anseriformes , the Charadriiformes are the only other order of modern bird to have an established fossil record within the late Cretaceous, alongside the other dinosaurs. Much of the Neornithes ' fossil record around the Cretaceous–Paleogene extinction event is made up of bits and pieces of birds which resemble this order. In many, this
486-1168: The Charadriiformes constitute a single large and very distinctive lineage of modern birds of their own. The auks, usually considered distinct because of their peculiar morphology, are more likely related to gulls, the "distinctness" being a result of adaptation for diving. The order Charadriiformes contains 3 suborders , 19 families and 391 species. Burhinidae – stone-curlews, thick-knees (10 species) Pluvianellidae – Magellanic plover Chionidae – sheathbills (2 species) Pluvianidae – Egyptian plover Charadriidae – plovers (69 species) Recurvirostridae – stilts, avocets (10 species) Ibidorhynchidae – ibisbill Haematopodidae – oystercatchers (12 species) Scolopacidae – sandpipers, snipes (98 species) Rostratulidae – painted-snipes (3 species) Jacanidae – jacanas (8 species) Pedionomidae – plains-wanderer Thinocoridae – seedsnipes (4 species) Turnicidae – buttonquails (18 species) Dromadidae – crab-plover Glareolidae – coursers, pratincoles (17 species) Laridae – gulls, terns, skimmers (103 species) Stercorariidae – skuas (7 species) Alcidae – auks (25 species) That
513-589: The Neoaves. The early diversification of the various neoavian groups occurred very rapidly around the Cretaceous–Paleogene extinction event , and attempts to resolve their relationships with each other have resulted initially in much controversy. The early diversification of the various neoavian groups occurred very rapidly around the Cretaceous–Paleogene extinction event . As a result of the rapid radiation, attempts to resolve their relationships have produced conflicting results, some quite controversial, especially in
540-495: The earlier studies. Nevertheless, some recent large phylogenomic studies of Neoaves have led to much progress on defining orders and supraordinal groups within Neoaves. Still, the studies have failed to produce to a consensus on an overall high order topology of these groups. A genomic study of 48 taxa by Jarvis and colleagues in 2014 divided Neoaves into two main clades, Columbea and Passerea , but an analysis of 198 taxa by Prum and colleagues in 2015 recovered different groupings for
567-482: The earliest split in Neoaves. A reanalysis with an extended dataset by Reddy and colleagues in 2017 suggested this was due to the type of sequence data, with coding sequences favouring the Prum topology. The disagreement on topology even with large phylogenomic studies led Alexander Suh in 2016 to propose a hard polytomy of nine clades as the base of Neoaves. An analysis by Houde and colleagues in 2019 recovered Columbea and
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#1732773285574594-451: The fundamental unit of cladistics , a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population , or a species ( extinct or extant ). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over
621-546: The group consists of a common ancestor with all its descendant branches. Rodents, for example, are a branch of mammals that split off after the end of the period when the clade Dinosauria stopped being the dominant terrestrial vertebrates 66 million years ago. The original population and all its descendants are a clade. The rodent clade corresponds to the order Rodentia, and insects to the class Insecta. These clades include smaller clades, such as chipmunk or ant , each of which consists of even smaller clades. The clade "rodent"
648-590: The last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic . Some of the relationships between organisms that the molecular biology arm of cladistics has revealed include that fungi are closer relatives to animals than they are to plants, archaea are now considered different from bacteria , and multicellular organisms may have evolved from archaea. The term "clade"
675-518: The latter term coined by Ernst Mayr (1965), derived from "clade". The results of phylogenetic/cladistic analyses are tree-shaped diagrams called cladograms ; they, and all their branches, are phylogenetic hypotheses. Three methods of defining clades are featured in phylogenetic nomenclature : node-, stem-, and apomorphy-based (see Phylogenetic nomenclature§Phylogenetic definitions of clade names for detailed definitions). The relationship between clades can be described in several ways: The age of
702-544: The spread of viral infections . HIV , for example, has clades called subtypes, which vary in geographical prevalence. HIV subtype (clade) B, for example is predominant in Europe, the Americas and Japan, whereas subtype A is more common in east Africa. Charadriiformes See text. Charadriiformes ( / k ə ˈ r æ d r i . ɪ f ɔːr m iː z / , from Charadrius , the type genus of family Charadriidae )
729-453: Was formerly divided into three suborders: The Sibley-Ahlquist taxonomy lumps all the Charadriiformes together with other seabirds and birds of prey into a greatly enlarged order Ciconiiformes . However, the resolution of the DNA-DNA hybridization technique used by Sibley & Ahlquist was not sufficient to properly resolve the relationships in this group, and indeed it appears as if
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