An evolutionary lineage is a temporal series of populations, organisms, cells, or genes connected by a continuous line of descent from ancestor to descendant. Lineages are subsets of the evolutionary tree of life . Lineages are often determined by the techniques of molecular systematics .
28-616: Salmonidae ( / s æ l ˈ m ɒ n ɪ d iː / , lit. "salmon-like") is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes ( / s æ l ˈ m ɒ n ɪ f ɔːr m iː z / , lit. "salmon-shaped"), consisting of 11 extant genera and over 200 species collectively known as " salmonids " or " salmonoids ". The family includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), char , graylings , freshwater whitefishes , taimens and lenoks , all coldwater mid- level predatory fish that inhabit
56-709: A monophyletic group. The order Salmoniformes first appeared during the Santonian and Campanian stages of the Late Cretaceous , and is most closely related to pike and mudminnows in the order Esociformes , to the extent that some authors have grouped the Esociformes within the Salmoniformes. Although it is assumed that salmon and pike diverged from one another during the Cretaceous, no definitive salmonids appear before
84-489: A phylogenetic tree . A lineage is a single line of descent or linear chain within the tree, while a clade is a (usually branched) monophyletic group, containing a single ancestor and all its descendants. Phylogenetic trees are typically created from DNA , RNA or protein sequence data. Apart from this, morphological differences and similarities have been, and still are used to create phylogenetic trees. Sequences from different individuals are collected and their similarity
112-422: A closer examination of the salmonid genome, and has allowed for a more precise dating of the whole-genome duplication of the group, that places the latest possible date for the event at 88 million years ago. This more precise dating and examination of the salmonid whole-genome duplication event has allowed more speculation on the radiation of species within the group. Historically, the whole-genome duplication event
140-554: 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. The naming of families is codified by various international bodies using the following suffixes: 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
168-519: A new distinct descendant clade. Just as a map is a scaled approximation of true geography , a phylogenetic tree is an approximation of the true complete evolutionary relationships. For example, in a full tree of life, the entire clade of animals can be collapsed to a single branch of the tree. However, this is merely a limitation of rendering space. In theory, a true and complete tree for all living organisms or for any DNA sequence could be generated. Nevertheless, phylogenies can sometimes appear in
196-440: A non-treelike form. Branches on the tree of life may grow together, a phenomenon called reticulation , which occurs due to different biological processes. Another process, introgression , occurs when hybrids between distinct lineages transfer novel genetic material through subsequent crossing. In other cases, hybrid speciation takes place when lineages hybridize to form a new, distinct lineage. Horizontal gene transfer, involving
224-566: A single row of sharp teeth . Although the smallest salmonid species is just 13 cm (5.1 in) long for adults, most salmonids are much larger, with the largest reaching 2 m (6 ft 7 in). All salmonids are migratory fish that spawn in the shallow gravel beds of freshwater headstreams , spend the growing juvenile years in rivers , creeks , small lakes and wetlands , but migrate downstream upon maturity and spend most of their adult lives at much larger waterbodies. Many salmonid species are euryhaline and migrate to
252-648: Is an archaic salmonid, representing an important stage in salmonid evolution. Fossil scales of coregonines are known from the Late Eocene or Early Oligocene of California. A gap appears in the salmonine fossil record after E. driftwoodensis until about 7 million years ago ( mya ), in the Late Miocene , when trout-like fossils appear in Idaho , in the Clarkia Lake beds . Several of these species appear to be Oncorhynchus —
280-499: Is commonly referred to as the "walnut family". 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
308-480: Is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between order and genus . 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
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#1732856033068336-480: Is quantified. Mathematical procedures are used to cluster individuals by similarity. Members of a species are considered to evolve as a single unit (or lineage) when they repeatedly share the same genes. The nodes would represent a split in lineage due to a breaking of genetic connections: when a single lineage is divided into two subsets, with the individuals not exchanging genes, they will accumulate differences in genes. If they do not fuse back again, it will create
364-437: Is still partially-tetraploid. Around half of the duplicated protein-coding genes have been deleted, but all apparent miRNA sequences still show full duplication, with potential to influence regulation of the rainbow trout's genome. This pattern of partial tetraploidy is thought to be reflected in the rest of extant salmonids. The first fossil species representing a true salmonid fish ( E. driftwoodensis ) does not appear until
392-476: The Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family. 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. Lineage (evolution) Lineages are typically visualized as subsets of
420-569: The Eocene . The Salmonidae first appear in the fossil record in the Early Eocene with Eosalmo driftwoodensis , a stem- salmonine , which was first described from fossils found at Driftwood Creek , central British Columbia , and has been recovered from most sites in the Eocene Okanagan Highlands . This genus shares traits found in all three subfamily lineages. Hence, E. driftwoodensis
448-415: The biomass transfer provided by their mass migration from oceanic to inland waterbodies. Current salmonids comprise three main clades taxonomically treated as subfamilies : Coregoninae ( freshwater whitefishes ), Thymallinae ( graylings ), and Salmoninae ( trout , salmon , char , taimens and lenoks ). Generally, all three lineages are accepted to allocate a suite of derived traits indicating
476-682: The sea or brackish estuaries as soon as they approach adulthood, returning to the upper streams only to reproduce. Such sea-run life cycle is described as anadromous , and other freshwater salmonids that migrate purely between lakes and rivers are considered potamodromous . Salmonids are carnivorous predators of the middle food chain , feeding on smaller fish, crustaceans , aquatic insects and larvae , tadpoles and sometimes fish eggs (even those of their own kind), and in turn being preyed upon by larger predators. Many species of salmonids are thus considered keystone organisms important for both freshwater and terrestrial ecosystems due to
504-550: The subarctic and cool temperate waters of the Northern Hemisphere . The Atlantic salmon ( Salmo salar ), whose Latin name became that of its genus Salmo , is also the eponym of the family and order names. Salmonids have a relatively primitive appearance among teleost fish, with the pelvic fins being placed far back, and an adipose fin towards the rear of the back. They have slender bodies with rounded scales and forked tail fins , and their mouths contain
532-1029: The superorder Protacanthopterygii . The only extant family within Salmoniformes, Salmonidae, is divided into three subfamilies and around 10 genera containing about 220 species . The concepts of the number of species recognised vary among researchers and authorities; the numbers presented below represent the higher estimates of diversity: Prosopium [REDACTED] Stenodus [REDACTED] Coregonus [REDACTED] Thymallus [REDACTED] Salmo [REDACTED] Salvelinus (incl. Salvethymus ) [REDACTED] Oncorhynchus [REDACTED] Brachymystax Parahucho [REDACTED] Hucho [REDACTED] Order Salmoniformes The following table shows results of hybrid crossbreeding combination in Salmonidae. note :- : The identical kind, O : (survivability), X : (Fatality) Family (biology) Family ( Latin : familia , pl. : familiae )
560-507: The Pliocene. Suggestions have gone back as far as the Early Miocene (about 20 mya). Based on the most current evidence, salmonids diverged from the rest of teleost fish no later than 88 million years ago, during the late Cretaceous . This divergence was marked by a whole-genome duplication event in the ancestral salmonid, where the diploid ancestor became tetraploid . This duplication is
588-583: The current genus for Pacific salmon and Pacific trout. The presence of these species so far inland established that Oncorhynchus was not only present in the Pacific drainages before the beginning of the Pliocene (~5–6 mya), but also that rainbow and cutthroat trout , and Pacific salmon lineages had diverged before the beginning of the Pliocene. Consequently, the split between Oncorhynchus and Salmo (Atlantic salmon and European trout) must have occurred well before
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#1732856033068616-530: 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 ). In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and
644-408: The fourth of its kind to happen in the evolutionary lineage of the salmonids, with two having occurred commonly to all bony vertebrates, and another specifically in the teleost fishes. Extant salmonids all show evidence of partial tetraploidy, as studies show the genome has undergone selection to regain a diploid state. Work done in the rainbow trout ( Onchorhynchus mykiss ) has shown that the genome
672-426: The middle Eocene. This fossil already displays traits associated with extant salmonids, but as the genome of E. driftwoodensis cannot be sequenced, it cannot be confirmed if polyploidy was present in this animal at this point in time. This fossil is also significantly younger than the proposed salmonid divergence from the rest of the teleost fishes, and is the earliest confirmed salmonid currently known. This means that
700-440: The salmonids have a ghost lineage of approximately 33 million years. Given a lack of earlier transition fossils, and the inability to extract genomic data from specimens other than extant species, the dating of the whole-genome duplication event in salmonids was historically a very broad categorization of times, ranging from 25 to 100 million years in age. New advances in calibrated relaxed molecular clock analyses have allowed for
728-567: 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
756-541: 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 ). In zoology ,
784-555: Was thought to be the reason for the variation within Salmonidae. Current evidence done with molecular clock analyses revealed that much of the speciation of the group occurred during periods of intense climate change associated with the last ice ages, with especially high speciation rates being observed in salmonids that developed an anadromous lifestyle. Together with the closely related orders Esociformes ( pikes and mudminnows ), Osmeriformes ( true smelts ) and Argentiniformes ( marine smelts and barreleyes ), Salmoniformes comprise
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