Sterculiaceae was a family of flowering plant based on the genus Sterculia . Genera formerly included in Sterculiaceae are now placed in the family Malvaceae , in the subfamilies: Byttnerioideae , Dombeyoideae , Helicteroideae and Sterculioideae .
41-743: As traditionally circumscribed the Sterculiaceae, Malvaceae , Bombacaceae , and Tiliaceae comprise the "core Malvales " of the Cronquist system and the close relationship among these families is generally recognized. Sterculiaceae may be separated from Malvaceae sensu stricto by the smooth surface of the pollen grains and the bilocular anthers . Numerous phylogenetic studies have revealed that Sterculiaceae, Tiliaceae and Bombacaceae as traditionally defined are cladistically polyphyletic . The APG and APG II systems unite Bombacaceae, Malvaceae sensu stricto , Sterculiaceae and Tiliaceae into
82-446: A t e s {\displaystyle n.states} , c i occupies a range from 1 to ( n . s t a t e s − 1 ) / ( n . t a x a − ⌈ n . t a x a / n . s t a t e s ⌉ ) {\displaystyle (n.states-1)/(n.taxa-\lceil n.taxa/n.states\rceil )} . The retention index (RI)
123-445: A metric to measure how consistent a candidate cladogram is with the data. Most cladogram algorithms use the mathematical techniques of optimization and minimization. In general, cladogram generation algorithms must be implemented as computer programs, although some algorithms can be performed manually when the data sets are modest (for example, just a few species and a couple of characteristics). Some algorithms are useful only when
164-540: A character in a phylogenetic analysis as they do not contribute anything to our understanding of relationships. However, homoplasy is often not evident from inspection of the character itself (as in DNA sequence, for example), and is then detected by its incongruence (unparsimonious distribution) on a most-parsimonious cladogram. Note that characters that are homoplastic may still contain phylogenetic signal . A well-known example of homoplasy due to convergent evolution would be
205-422: A dataset, the degree to which each character carries phylogenetic information, and the fashion in which additive characters are coded, rendering it unfit for purpose. c i occupies a range from 1 to 1/[ n.taxa /2] in binary characters with an even state distribution; its minimum value is larger when states are not evenly spread. In general, for a binary or non-binary character with n . s t
246-457: A larger clade. The incongruence length difference test (ILD) is a measurement of how the combination of different datasets (e.g. morphological and molecular, plastid and nuclear genes) contributes to a longer tree. It is measured by first calculating the total tree length of each partition and summing them. Then replicates are made by making randomly assembled partitions consisting of the original partitions. The lengths are summed. A p value of 0.01
287-452: A more and more popular way to infer phylogenetic hypotheses. Using a parsimony criterion is only one of several methods to infer a phylogeny from molecular data. Approaches such as maximum likelihood , which incorporate explicit models of sequence evolution, are non-Hennigian ways to evaluate sequence data. Another powerful method of reconstructing phylogenies is the use of genomic retrotransposon markers , which are thought to be less prone to
328-482: A more widely circumscribed Malvaceae, i.e., Malvaceae sensu lato . In that view the taxa formerly classified in Sterculiaceae are treated in the subfamilies Byttnerioideae , Dombeyoideae , Helicteroideae and Sterculioideae of the Malvaceae sensu lato . The Thorne system takes an intermediate approach in combining the bulk of the traditional Sterculiaceae (but not including Sterculia itself) with elements of
369-489: A vein ends at the tip of each tooth (malvoid teeth). Stipules are present. The stems contain mucous canals and often also mucous cavities. Hairs are common, and are most typically stellate . Stems of Bombacoideae are often covered in thick prickles. The flowers are commonly borne in definite or indefinite axillary inflorescences , which are often reduced to a single flower, but may also be cauliflorous , oppositifolious, or terminal. They often bear supernumerary bracts in
410-410: Is a character state that is shared by two or more taxa due to some cause other than common ancestry. The two main types of homoplasy are convergence (evolution of the "same" character in at least two distinct lineages) and reversion (the return to an ancestral character state). Characters that are obviously homoplastic, such as white fur in different lineages of Arctic mammals, should not be included as
451-1278: Is based on the second circumscription, as presented by the Angiosperm Phylogeny Website . The Malvaceae s.l. (hereafter simply "Malvaceae") comprise nine subfamilies. A tentative cladogram of the family is shown below. The diamond denotes a poorly supported branching (<80%). Byttnerioideae : 26 genera, 650 species, pan-tropical, especially South America Grewioideae : 25 genera, 770 species, " pantropical " Sterculioideae : 12 genera, 430 species, pan-tropical Tilioideae : three genera, 50 species, northern temperate regions and Central America Dombeyoideae : about 20 genera, about 380 species, palaeo-tropical, especially Madagascar and Mascarenes Brownlowioideae : eight genera, about 70 species, especially palaeo-tropical Helicteroideae : eight to 12 genera, 10 to 90 species, tropical, especially Southeast Asia Malvoideae : 78 genera, 1,670 species, temperate to tropical Bombacoideae : 12 genera, 120 species, tropical, especially Africa and America Until recently, relationships between these subfamilies were either poorly supported or almost completely obscure. Continuing disagreements focused primarily on
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#1732801249755492-411: Is obtained for 100 replicates if 99 replicates have longer combined tree lengths. Some measures attempt to measure the amount of homoplasy in a dataset with reference to a tree, though it is not necessarily clear precisely what property these measures aim to quantify The consistency index (CI) measures the consistency of a tree to a set of data – a measure of the minimum amount of homoplasy implied by
533-413: Is superior, with axial placentation, with capitate or lobed stigma. The flowers have nectaries made of many tightly packed glandular hairs , usually positioned on the sepals. The fruits are most often loculicidal capsules , schizocarps or nuts . Self-pollination is often avoided by means of protandry . Most species are entomophilous (pollinated by insects). Bees from the tribe Emphorini of
574-535: Is the fruit of the durian . A number of species, including Hibiscus syriacus , Hibiscus rosa-sinensis and Alcea rosea are garden plants. Cladogram A cladogram (from Greek clados "branch" and gramma "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with
615-526: Is usually done by comparison to the character states of one or more outgroups . States shared between the outgroup and some members of the in-group are symplesiomorphies; states that are present only in a subset of the in-group are synapomorphies. Note that character states unique to a single terminal (autapomorphies) do not provide evidence of grouping. The choice of an outgroup is a crucial step in cladistic analysis because different outgroups can produce trees with profoundly different topologies. A homoplasy
656-564: The Apidae (including Ptilothrix , Diadasia , and Melitoma ) are known to specialize on the plants. A number of species are pests in agriculture , including Abutilon theophrasti and Modiola caroliniana , and others that are garden escapees. Cotton (four species of Gossypium ), kenaf ( Hibiscus cannabinus ), cacao ( Theobroma cacao ), kola nut ( Cola spp. ), and okra ( Abelmoschus esculentus ) are important agricultural crops. The fruit and leaves of baobabs are edible, as
697-442: The "core Malvales" families used to be defined on the basis of shared "malvean affinities". These included the presence of malvoid teeth, stems with mucilage canals, and stratified wedge-shaped phloem. These affinities were problematic because they were not always shared within the core families. Later studies revealed more unambiguous synapomorphies within Malvaceae s.l.. Synapomorphies identified within Malvaceae s.l. include
738-744: The Sterculioideae was most likely to be a monophyletic group, and that it had four major clades within it. However, the relationships between the clades were not resolved. Malvaceae See List of Malvaceae genera Malvaceae ( / m æ l ˈ v eɪ s i ˌ aɪ , - s iː ˌ iː / ), or the mallows , is a family of flowering plants estimated to contain 244 genera with 4225 known species. Well-known members of economic importance include okra , cotton , cacao , roselle and durian . There are also some genera containing familiar ornamentals, such as Alcea (hollyhock), Malva (mallow), and Tilia (lime or linden tree). The genera with
779-429: The basis that genetics studies have shown the commonly recognised families Bombacaceae , Tiliaceae , and Sterculiaceae , which have always been considered closely allied to Malvaceae s.s. , are not monophyletic groups. The Malvaceae can be expanded to include all of these families so as to compose a monophyletic group. Adopting this circumscription, the Malvaceae incorporate a much larger number of genera. This article
820-431: The character, "presence of wings". Although the wings of birds, bats , and insects serve the same function, each evolved independently, as can be seen by their anatomy . If a bird, bat, and a winged insect were scored for the character, "presence of wings", a homoplasy would be introduced into the dataset, and this could potentially confound the analysis, possibly resulting in a false hypothesis of relationships. Of course,
861-434: The characteristic data are molecular (DNA, RNA); other algorithms are useful only when the characteristic data are morphological. Other algorithms can be used when the characteristic data includes both molecular and morphological data. Algorithms for cladograms or other types of phylogenetic trees include least squares , neighbor-joining , parsimony , maximum likelihood , and Bayesian inference . Biologists sometimes use
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#1732801249755902-429: The correct circumscription of these subfamilies, including the preservation of the family Bombacaceae. A study published in 2021 presented a fully resolved phylogenetic framework for Malvaceae s.l. using genomic data for all nine subfamilies. Regarding the traditional Malvaceae s.s. , the subfamily Malvoideae approximately corresponds to that group. 245 genera are currently accepted. The relationships between
943-691: The dataset). The rescaled consistency index (RC) is obtained by multiplying the CI by the RI; in effect this stretches the range of the CI such that its minimum theoretically attainable value is rescaled to 0, with its maximum remaining at 1. The homoplasy index (HI) is simply 1 − CI. This measures the amount of homoplasy observed on a tree relative to the maximum amount of homoplasy that could theoretically be present – 1 − (observed homoplasy excess) / (maximum homoplasy excess). A value of 1 indicates no homoplasy; 0 represents as much homoplasy as there would be in
984-426: The flowers, with the main axis developing first. Bracts on the peduncle subtend axillary buds that become these lateral stalks. One bract within this whorl is a sterile bract. The bicolor unit is a variable structure in complexity, but the presence of fertile and sterile bracts is a salient characteristic. The English common name 'mallow' (also applied to other members of Malvaceae) comes from Latin malva (also
1025-534: The generation of cladograms, either on their own or in combination with morphology. The characteristics used to create a cladogram can be roughly categorized as either morphological (synapsid skull, warm blooded, notochord , unicellular, etc.) or molecular (DNA, RNA, or other genetic information). Prior to the advent of DNA sequencing, cladistic analysis primarily used morphological data. Behavioral data (for animals) may also be used. As DNA sequencing has become cheaper and easier, molecular systematics has become
1066-425: The inner surface of the sepals, but flowers of the subfamily Tiliodeae also have present nectaries on the petals. Malvean flowers also share a unifying structure known as a bicolor unit, named for its initial discovery in the flowers of Theobroma bicolor . The bicolor unit consists of an ordered inflorescence with determinate cymose structures. The inflorescence can branch off the main axis, creating separate orders of
1107-470: The largest numbers of species include Hibiscus (434 species), Pavonia (291 species), Sida (275 species), Ayenia (216 species), Dombeya (197 species), and Sterculia (181 species). The circumscription of the Malvaceae is controversial. The traditional Malvaceae sensu stricto comprise a very homogeneous and cladistically monophyletic group. Another major circumscription, Malvaceae sensu lato , has been more recently defined on
1148-705: The only reason a homoplasy is recognizable in the first place is because there are other characters that imply a pattern of relationships that reveal its homoplastic distribution. A cladogram is the diagrammatic result of an analysis, which groups taxa on the basis of synapomorphies alone. There are many other phylogenetic algorithms that treat data somewhat differently, and result in phylogenetic trees that look like cladograms but are not cladograms. For example, phenetic algorithms, such as UPGMA and Neighbor-Joining, group by overall similarity, and treat both synapomorphies and symplesiomorphies as evidence of grouping, The resulting diagrams are phenograms, not cladograms, Similarly,
1189-562: The presence of tile cells, trichomatous nectaries, and an inflorescence structure called a bicolor unit. Tile cells consist of vertically positioned cells interspersed between and dimensionally similar to procumbent ray cells. Evidence of Malvean wood fossils has confirmed their evolutionary link in Malvaceae s.l. , as well as explained their diverse structures. Flowers of Malvaceae s.l . exhibit nectaries consisting of densely arranged multicellular hairs resembling trichomes. In most of Malvaceae s.l. , these trichomatous nectaries are located on
1230-499: The problem of reversion that plagues sequence data. They are also generally assumed to have a low incidence of homoplasies because it was once thought that their integration into the genome was entirely random; this seems at least sometimes not to be the case, however. Researchers must decide which character states are "ancestral" ( plesiomorphies ) and which are derived ( synapomorphies ), because only synapomorphic character states provide evidence of grouping. This determination
1271-436: The program settles on a local minimum rather than the desired global minimum. To help solve this problem, many cladogram algorithms use a simulated annealing approach to increase the likelihood that the selected cladogram is the optimal one. The basal position is the direction of the base (or root) of a rooted phylogenetic tree or cladogram. A basal clade is the earliest clade (of a given taxonomic rank[a]) to branch within
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1312-405: The results of model-based methods (Maximum Likelihood or Bayesian approaches) that take into account both branching order and "branch length," count both synapomorphies and autapomorphies as evidence for or against grouping, The diagrams resulting from those sorts of analysis are not cladograms, either. There are several algorithms available to identify the "best" cladogram. Most algorithms use
1353-429: The same cladogram. A cladogram uses lines that branch off in different directions ending at a clade , a group of organisms with a last common ancestor . There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit
1394-664: The source for the English word " mauve "). Malva itself was ultimately derived from the word for the plant in ancient Mediterranean languages. Cognates of the word include Ancient Greek μαλάχη ( malákhē ) or μολόχη ( molókhē ), Modern Greek μολόχα ( molókha ), modern Arabic : ملوخية ( mulukhiyah ) and modern Hebrew : מלוחיה ( molokhia ). Most species are herbaceous plants or shrubs , but some are trees or lianas . Leaves are generally alternate , often palmately lobed or compound and palmately veined. The margin may be entire, but when dentate ,
1435-466: The structure of a bicolor unit. They can be unisexual or bisexual, and are generally actinomorphic , often associated with conspicuous bracts, forming an epicalyx . They generally have five valvate sepals , most frequently basally connate , with five imbricate petals . The stamens are five to numerous, and connate at least at their bases, but often forming a tube around the pistils . The pistils are composed of two to many connate carpels . The ovary
1476-460: The term parsimony for a specific kind of cladogram generation algorithm and sometimes as an umbrella term for all phylogenetic algorithms. Algorithms that perform optimization tasks (such as building cladograms) can be sensitive to the order in which the input data (the list of species and their characteristics) is presented. Inputting the data in various orders can cause the same algorithm to produce different "best" cladograms. In these situations,
1517-447: The traditional Tiliaceae to form the family Byttneriaceae . Sterculiaceae had previously been recognized as a family by most systematists; in its traditional sense the family includes about 70 genera, totalling around 1,500 species of tropical trees and shrubs. The most famous products of the family are chocolate and cocoa from Theobroma cacao , followed by kola nuts . Many species yield timber. A 2006 molecular study indicated
1558-420: The traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other evolutionary narratives about ancestors. Although traditionally such cladograms were generated largely on the basis of morphological characters, DNA and RNA sequencing data and computational phylogenetics are now very commonly used in
1599-406: The tree. It is calculated by counting the minimum number of changes in a dataset and dividing it by the actual number of changes needed for the cladogram. A consistency index can also be calculated for an individual character i , denoted c i . Besides reflecting the amount of homoplasy, the metric also reflects the number of taxa in the dataset, (to a lesser extent) the number of characters in
1640-423: The user should input the data in various orders and compare the results. Using different algorithms on a single data set can sometimes yield different "best" cladograms, because each algorithm may have a unique definition of what is "best". Because of the astronomical number of possible cladograms, algorithms cannot guarantee that the solution is the overall best solution. A nonoptimal cladogram will be selected if
1681-399: Was proposed as an improvement of the CI "for certain applications" This metric also purports to measure of the amount of homoplasy, but also measures how well synapomorphies explain the tree. It is calculated taking the (maximum number of changes on a tree minus the number of changes on the tree), and dividing by the (maximum number of changes on the tree minus the minimum number of changes in