81-424: Antilope is a genus of twisted-horn bovid that contains a single living species, the blackbuck of South Asia . Two extinct species are also known. Many fossil antelopes were included in this genus, but have since been placed in new genera; for example the species formerly known as Antilope planicornis is now placed in its own genus, Nisidorcas . Bovid Alternate taxonomy: The Bovidae comprise
162-728: A bacterial genome over three types of outbreak contact networks—homogeneous, super-spreading, and chain-like. They summarized the resulting phylogenies with five metrics describing tree shape. Figures 2 and 3 illustrate the distributions of these metrics across the three types of outbreaks, revealing clear differences in tree topology depending on the underlying host contact network. Super-spreader networks give rise to phylogenies with higher Colless imbalance, longer ladder patterns, lower Δw, and deeper trees than those from homogeneous contact networks. Trees from chain-like networks are less variable, deeper, more imbalanced, and narrower than those from other networks. Scatter plots can be used to visualize
243-414: A different shape. The horns of female bovids are believed to have evolved for defence against predators or to express territoriality, as nonterritorial females, which are able to use crypsis for predator defence, often do not have horns. Females possess horns only in half of the bovid genera, and females in these genera are heavier than those in the rest. Females use horns mainly for stabbing. In bovids,
324-499: A disproof of a previously widely accepted theory. During the late 19th century, Ernst Haeckel 's recapitulation theory , or "biogenetic fundamental law", was widely popular. It was often expressed as " ontogeny recapitulates phylogeny", i.e. the development of a single organism during its lifetime, from germ to adult, successively mirrors the adult stages of successive ancestors of the species to which it belongs. But this theory has long been rejected. Instead, ontogeny evolves –
405-667: A few such as the buffalo, bushbuck, reedbuck, and grysbok are exceptions. Social activity and feeding usually peak during dawn and dusk. The bovids usually rest before dawn, during midday, and after dark. Grooming is usually by licking with the tongue. Rarely do antelopes roll in mud or dust. Wildebeest and buffalo usually wallow in mud, whereas the hartebeest and topi rub their heads and horns in mud and then smear it over their bodies. Bovids use different forms of vocal, olfactory, and tangible communication. These involve varied postures of neck, head, horns, hair, legs, and ears to convey sexual excitement, emotional state, or alarm. One such expression
486-536: A language as an evolutionary system. The evolution of human language closely corresponds with human's biological evolution which allows phylogenetic methods to be applied. The concept of a "tree" serves as an efficient way to represent relationships between languages and language splits. It also serves as a way of testing hypotheses about the connections and ages of language families. For example, relationships among languages can be shown by using cognates as characters. The phylogenetic tree of Indo-European languages shows
567-509: A level muzzle. Fighting techniques differ amongst the bovid families and also depend on their build. While the hartebeest fight on knees, others usually fight on all fours. Gazelles of various sizes use different methods of combat. Gazelles usually box, and in serious fights may clash and fence, consisting of hard blows from short range. Ibex, goat and sheep males stand upright and clash into each other downwards. Wildebeest use powerful head butting in aggressive clashes. If horns become entangled,
648-465: A pale white (as in the Arabian oryx ) to black (as in the black wildebeest ). However, only the intermediate shades, such as brown and reddish brown (as in the reedbuck ), are commonly observed. In several species, females and juveniles exhibit a light-coloured coat, while those of males darken with age. As in the wildebeest , the coat may be marked with prominent or faint stripes. In some species such as
729-487: A permanent sheath of keratin . Most bovids bear 30 to 32 teeth. Most bovids are diurnal . Social activity and feeding usually peak during dawn and dusk. Bovids typically rest before dawn, during midday, and after dark. They have various methods of social organisation and social behaviour , which are classified into solitary and gregarious behaviour. Bovids use different forms of vocal, olfactory, and tangible communication. Most species alternately feed and ruminate throughout
810-825: A permanent sheath of keratin. Although horns occur in a single pair on almost all bovid species, there are exceptions such as the four-horned antelope and the Jacob sheep . The unique horn structure is the only unambiguous morphological feature of bovids that distinguishes them from other pecorans . A high correlation exists between horn morphology and fighting behaviour of the individual. For instance, long horns are intended for wrestling and fencing, whereas curved horns are used in ramming. Males with horns directed inwards are monogamous and solitary, while those with horns directed outwards tend to be polygynous . These results were independent of body size. Male horn development has been linked to sexual selection , Horns are small spikes in
891-417: A phylogenetic tree can be living taxa or fossils , which represent the present time or "end" of an evolutionary lineage, respectively. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An unrooted tree diagram (a network) makes no assumption about the ancestral line, and does not show the origin or "root" of the taxa in question or
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#1732858297870972-693: A shared evolutionary history. There are debates if increasing the number of taxa sampled improves phylogenetic accuracy more than increasing the number of genes sampled per taxon. Differences in each method's sampling impact the number of nucleotide sites utilized in a sequence alignment, which may contribute to disagreements. For example, phylogenetic trees constructed utilizing a more significant number of total nucleotides are generally more accurate, as supported by phylogenetic trees' bootstrapping replicability from random sampling. The graphic presented in Taxon Sampling, Bioinformatics, and Phylogenomics , compares
1053-462: A significant source of error within phylogenetic analysis occurs due to inadequate taxon samples. Accuracy may be improved by increasing the number of genetic samples within its monophyletic group. Conversely, increasing sampling from outgroups extraneous to the target stratified population may decrease accuracy. Long branch attraction is an attributed theory for this occurrence, where nonrelated branches are incorrectly classified together, insinuating
1134-631: A single tree with true claim. The same process can be applied to texts and manuscripts. In Paleography , the study of historical writings and manuscripts, texts were replicated by scribes who copied from their source and alterations - i.e., 'mutations' - occurred when the scribe did not precisely copy the source. Phylogenetics has been applied to archaeological artefacts such as the early hominin hand-axes, late Palaeolithic figurines, Neolithic stone arrowheads, Bronze Age ceramics, and historical-period houses. Bayesian methods have also been employed by archaeologists in an attempt to quantify uncertainty in
1215-594: A small group of taxa to represent the evolutionary history of its broader population. This process is also known as stratified sampling or clade-based sampling. The practice occurs given limited resources to compare and analyze every species within a target population. Based on the representative group selected, the construction and accuracy of phylogenetic trees vary, which impacts derived phylogenetic inferences. Unavailable datasets, such as an organism's incomplete DNA and protein amino acid sequences in genomic databases, directly restrict taxonomic sampling. Consequently,
1296-592: A species to uncover either a higher abundance of important bioactive compounds (e.g., species of Taxus for taxol) or natural variants of known pharmaceuticals (e.g., species of Catharanthus for different forms of vincristine or vinblastine). Phylogenetic analysis has also been applied to biodiversity studies within the fungi family. Phylogenetic analysis helps understand the evolutionary history of various groups of organisms, identify relationships between different species, and predict future evolutionary changes. Emerging imagery systems and new analysis techniques allow for
1377-513: A tribe of Caprinae, in Africa date back to the late Miocene. The earliest Hippotragine fossils date back to the late Miocene, and were excavated from sites such as Lothagam and Awash Valley . The first African fossils of Reduncinae date back to 6-7 Mya. Reduncinae and Peleinae probably diverged in the mid-Miocene. All bovids have the similar basic form - a snout with a blunt end, one or more pairs of horns (generally present on males) immediately after
1458-550: Is "tree shape." These approaches, while computationally intensive, have the potential to provide valuable insights into pathogen transmission dynamics. The structure of the host contact network significantly impacts the dynamics of outbreaks, and management strategies rely on understanding these transmission patterns. Pathogen genomes spreading through different contact network structures, such as chains, homogeneous networks, or networks with super-spreaders, accumulate mutations in distinct patterns, resulting in noticeable differences in
1539-577: Is believed to have come into being in the Pliocene, but became extinct in the middle Pleistocene . Several genera of Hippotraginae are known since the Pliocene and Pleistocene. This subfamily appears to have diverged from the Alcelaphinae in the latter part of early Miocene. The Bovinae are believed to have diverged from the rest of the Bovidae in the early Miocene . The Boselaphini became extinct in Africa in
1620-708: Is disputed, with suggestions of as many as ten and as few as two subfamilies. However, molecular, morphological and fossil evidence indicates the existence of eight distinct subfamilies: Aepycerotinae (consisting of just the impala), Alcelaphinae (bontebok, hartebeest, wildebeest and relatives), Antilopinae (several antelopes, gazelles, and relatives), Bovinae (cattle, buffaloes, bison and other antelopes), Caprinae (goats, sheep, ibex, serows and relatives), Cephalophinae (duikers), Hippotraginae (addax, oryx and relatives) and Reduncinae (reedbuck and kob antelopes). In addition, three extinct subfamilies are known: Hypsodontinae (mid- Miocene ), Oiocerinae ( Turolian ) and
1701-487: Is in the savannas of Eastern Africa . Other bovid species also occur in Europe, Asia, and North America. Bovidae includes a number of domesticated species, including three whose use has spread worldwide, namely cattle , sheep , and goats . Dairy products , such as milk , butter , and cheese , are manufactured largely from domestic cattle. Bovids are also raised for their leather , meat , and wool . The name "Bovidae"
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#17328582978701782-402: Is the flehmen response . Bovids usually stand motionless, with the head high and an intent stare, when they sense danger. Some like the impala, kudu, and eland can even leap to heights of a few feet. Bovids may roar or grunt to caution others and warn off predators. Bovids such as gazelles stot or pronk in response to predators, making high leaps on stiff legs, indicating honestly both that
1863-437: Is the identification, naming, and classification of organisms. Compared to systemization, classification emphasizes whether a species has characteristics of a taxonomic group. The Linnaean classification system developed in the 1700s by Carolus Linnaeus is the foundation for modern classification methods. Linnaean classification relies on an organism's phenotype or physical characteristics to group and organize species. With
1944-718: Is the only bovid that is both solitary and not territorial. This antelope hardly displays aggression, and tends to isolate itself or form loose herds, though in a favourable habitat, several bushbuck may be found quite close to one another. Excluding the cephalophines (duikers), tragelaphines (spiral-horned antelopes) and the neotragines, most African bovids are gregarious and territorial. Males are forced to disperse on attaining sexual maturity, and must form their own territories, while females are not required to do so. Males that do not hold territories form bachelor herds. Competition takes place among males to acquire dominance, and fights tend to be more rigorous in limited rutting seasons . With
2025-444: Is the study of the evolutionary history of life using genetics, which is known as phylogenetic inference . It establishes the relationship between organisms with the empirical data and observed heritable traits of DNA sequences, protein amino acid sequences, and morphology . The results are a phylogenetic tree —a diagram setting the hypothetical relationships between organisms and their evolutionary history. The tips of
2106-1113: The Antilopinae , was later placed in its own subfamily, Pantholopinae . However, molecular and morphological analysis supports the inclusion of Pantholops in Caprinae . Below is a cladogram based on Yang et al . , 2013 and Calamari, 2021: Bovini (bison, buffalo, cattle, etc.) [REDACTED] Boselaphini (nilgai and four-horned antelope) [REDACTED] Tragelaphini (kudus, nyalas etc.) [REDACTED] Aepycerotinae (impala) [REDACTED] Nesotraginae (suni and bates's antelope) Antilopinae (gazelles, springbok, dik-dik, royal antelope, saiga, etc.) [REDACTED] Cephalophinae (duikers etc.) [REDACTED] Oreotraginae (klipspringer) Reduncinae (kobs, reedbucks, waterbucks etc.) [REDACTED] Caprinae (chamois, sheep, ibexes, goats, muskox, etc.) [REDACTED] Alcelaphinae (hartebeest, topi, wildebeest etc.) [REDACTED] Hippotraginae (sable antelopes, oryxes etc.) [REDACTED] Alternatively, all members of
2187-491: The addax , the coat colour can vary by the season. Scent glands and sebaceous glands are often present. Some species, such as the gemsbok , sable antelope , and Grant's gazelle , are camouflaged with strongly disruptive facial markings that conceal the highly recognisable eye. Many species, such as gazelles, may be made to look flat, and hence to blend into the background, by countershading . The outlines of many bovids are broken up with bold disruptive colouration,
2268-410: The biological family of cloven-hoofed , ruminant mammals that includes cattle , bison , buffalo , antelopes (including goat-antelopes ), sheep and goats . A member of this family is called a bovid . With 143 extant species and 300 known extinct species , the family Bovidae consists of 11 (or two) major subfamilies and thirteen major tribes. The family evolved 20 million years ago, in
2349-399: The dental pad , that provides a surface to grip grasses and foliage. They are hypsodont and selenodont , since the molars and premolars are low- crowned and crescent-shaped cusps . The lower incisors and canines project forward. The incisors are followed by a long toothless gap, known as the diastema . The general dental formula for bovids is 0.0.2-3.3 3.1.3.3 . Most members of
2430-524: The Aegodontia, can be classified within the subfamily Antilopinae, with the individual subfamilies being tribes in this treatment. In the early Miocene, bovids began diverging from the cervids (deer) and giraffids . The earliest bovids, whose presence in Africa and Eurasia in the latter part of early Miocene (20 Mya ) has been ascertained, were small animals, somewhat similar to modern gazelles , and probably lived in woodland environments. Eotragus ,
2511-440: The Bovidae, where for example Bos , Ovis , bontebok and gemsbok have white stockings. Again, communication is the likely function. Excepting some domesticated forms, all male bovids have horns, and in many species, females, too, possess horns. The size and shape of the horns vary greatly, but the basic structure is a pair of simple bony protrusions without branches, often having a spiral, twisted, or fluted form, each covered in
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2592-552: The Bovidae-Moschidae clade 27 to 28 million years ago. The following cladogram is based on the 2003 study. Tragulidae [REDACTED] Antilocapridae [REDACTED] Giraffidae [REDACTED] Cervidae [REDACTED] Moschidae [REDACTED] Bovidae [REDACTED] Molecular studies have supported monophyly in the family Bovidae (a group of organisms comprises an ancestral species and all their descendants). The number of subfamilies in Bovidae
2673-545: The German Phylogenie , introduced by Haeckel in 1866, and the Darwinian approach to classification became known as the "phyletic" approach. It can be traced back to Aristotle , who wrote in his Posterior Analytics , "We may assume the superiority ceteris paribus [other things being equal] of the demonstration which derives from fewer postulates or hypotheses." The modern concept of phylogenetics evolved primarily as
2754-410: The Pliocene. By the late Miocene, around 10 Mya, the bovids rapidly diversified , leading to the creation of 70 new genera. This late Miocene radiation was partly because many bovids became adapted to more open, grassland habitats. The Aepycerotinae first appeared in the late Miocene, and no significant difference in the sizes of the primitive and modern impala has been noted. Fossils of ovibovines,
2835-645: The absence of genetic recombination . Phylogenetics can also aid in drug design and discovery. Phylogenetics allows scientists to organize species and can show which species are likely to have inherited particular traits that are medically useful, such as producing biologically active compounds - those that have effects on the human body. For example, in drug discovery, venom -producing animals are particularly useful. Venoms from these animals produce several important drugs, e.g., ACE inhibitors and Prialt ( Ziconotide ). To find new venoms, scientists turn to phylogenetics to screen for closely related species that may have
2916-440: The afternoon. Temperature is regulated through sweating in cattle, whereas goats use panting for the same. The right lung , consisting of four to five lobes , is around 1.5 times larger than the left, which has three lobes. Most bovids bear 30 to 32 teeth. While the upper incisors are absent, the upper canines are either reduced or absent. Instead of the upper incisors, bovids have a thick and tough layer of tissue, called
2997-414: The basis of a computational classifier used to analyze real-world outbreaks. Computational predictions of transmission dynamics for each outbreak often align with known epidemiological data. Different transmission networks result in quantitatively different tree shapes. To determine whether tree shapes captured information about underlying disease transmission patterns, researchers simulated the evolution of
3078-417: The beginning of the 21st century it was understood that the family Moschidae (musk deer) was sister to Cervidae . However, a 2003 phylogenetic study by Alexandre Hassanin (of National Museum of Natural History, France ) and colleagues, based on mitochondrial and nuclear analyses, revealed that Moschidae and Bovidae form a clade sister to Cervidae . According to the study, Cervidae diverged from
3159-436: The branching pattern and "degree of difference" to find a compromise between them. Usual methods of phylogenetic inference involve computational approaches implementing the optimality criteria and methods of parsimony , maximum likelihood (ML), and MCMC -based Bayesian inference . All these depend upon an implicit or explicit mathematical model describing the evolution of characters observed. Phenetics , popular in
3240-460: The characteristics of species to interpret their evolutionary relationships and origins. Phylogenetics focuses on whether the characteristics of a species reinforce a phylogenetic inference that it diverged from the most recent common ancestor of a taxonomic group. In the field of cancer research, phylogenetics can be used to study the clonal evolution of tumors and molecular chronology , predicting and showing how cell populations vary throughout
3321-409: The complex cellulose into simpler fatty acids , which are then absorbed through the rumen wall. Bovids have a long small intestine ; the length of the small intestine in cattle is 29–49 m (95–161 ft). Body temperature fluctuates through the day; for instance, in goats the temperature can change slightly from nearly 37 °C (99 °F) in the early morning to 40 °C (104 °F) in
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3402-400: The correctness of phylogenetic trees generated using fewer taxa and more sites per taxon on the x-axis to more taxa and fewer sites per taxon on the y-axis. With fewer taxa, more genes are sampled amongst the taxonomic group; in comparison, with more taxa added to the taxonomic sampling group, fewer genes are sampled. Each method has the same total number of nucleotide sites sampled. Furthermore,
3483-413: The data distribution. They may be used to quickly identify differences or similarities in the transmission data. Phylogenetic tools and representations (trees and networks) can also be applied to philology , the study of the evolution of oral languages and written text and manuscripts, such as in the field of quantitative comparative linguistics . Computational phylogenetics can be used to investigate
3564-592: The day. While small bovids forage in dense and closed habitat, larger species feed on high-fiber vegetation in open grasslands. Most bovids are polygynous . Mature bovids mate at least once a year and smaller species may even mate twice. In some species, neonate bovids remain hidden for a week to two months, regularly nursed by their mothers; in other species, neonates are followers, accompanying their dams, rather than tending to remain hidden. The greatest diversities of bovids occur in Africa . The maximum concentration of species
3645-426: The direction of inferred evolutionary transformations. In addition to their use for inferring phylogenetic patterns among taxa, phylogenetic analyses are often employed to represent relationships among genes or individual organisms. Such uses have become central to understanding biodiversity , evolution, ecology , and genomes . Phylogenetics is a component of systematics that uses similarities and differences of
3726-597: The discovery of more genetic relationships in biodiverse fields, which can aid in conservation efforts by identifying rare species that could benefit ecosystems globally. Whole-genome sequence data from outbreaks or epidemics of infectious diseases can provide important insights into transmission dynamics and inform public health strategies. Traditionally, studies have combined genomic and epidemiological data to reconstruct transmission events. However, recent research has explored deducing transmission patterns solely from genomic data using phylodynamics , which involves analyzing
3807-488: The dotted line represents a 1:1 accuracy between the two sampling methods. As seen in the graphic, most of the plotted points are located below the dotted line, which indicates gravitation toward increased accuracy when sampling fewer taxa with more sites per taxon. The research performed utilizes four different phylogenetic tree construction models to verify the theory; neighbor-joining (NJ), minimum evolution (ME), unweighted maximum parsimony (MP), and maximum likelihood (ML). In
3888-506: The duiker browse for a few hours during day or night. Feeding habits are related to body size; while small bovids forage in dense and closed habitat, larger species feed upon high-fiber vegetation in open grasslands. Subfamilies exhibit different feeding strategies. While Bovinae species graze extensively on fresh grass and diffused forage, Cephalophinae species (with the exception of Sylvicapra ) primarily consume fruits. Reduncinae and Hippotraginae species depend on unstable food sources, but
3969-492: The earliest known bovid, weighed 18 kg (40 lb) and was nearly the same in size as the Thomson's gazelle . Early in their evolutionary history, the bovids split into two main clades: Boodontia (of Eurasian origin) and Aegodontia (of African origin). This early split between Boodontia and Aegodontia has been attributed to the continental divide between these land masses. When these continents were later rejoined, this barrier
4050-419: The early Miocene . The bovids show great variation in size and pelage colouration. Except some domesticated forms , all male bovids have two or more horns , and in many species, females possess horns, too. The size and shape of the horns vary greatly, but the basic structure is always one or more pairs of simple bony protrusions without branches, often having a spiral, twisted or fluted form, each covered in
4131-510: The early Pliocene; their latest fossils were excavated in Langebaanweg (South Africa) and Lothagam (Kenya). The middle Miocene marked the spread of the bovids into China and the Indian subcontinent. According to Vrba, the radiation of the subfamily Alcelaphinae began in the latter part of middle Miocene. The Caprinae tribes probably diverged in the early middle Miocene. The Caprini emerged in
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#17328582978704212-668: The emergence of biochemistry , organism classifications are now usually based on phylogenetic data, and many systematists contend that only monophyletic taxa should be recognized as named groups. The degree to which classification depends on inferred evolutionary history differs depending on the school of taxonomy: phenetics ignores phylogenetic speculation altogether, trying to represent the similarity between organisms instead; cladistics (phylogenetic systematics) tries to reflect phylogeny in its classifications by only recognizing groups based on shared, derived characters ( synapomorphies ); evolutionary taxonomy tries to take into account both
4293-723: The exception of migratory males, males generally hold the same territory throughout their lives. In the waterbuck, some male individuals, known as "satellite males", may be allowed into the territories of other males and have to wait till the owner grows old so they may acquire his territory. Lek mating , where males gather together and competitively display to potential mates, is known to exist among topis , kobs , and lechwes . The tragelaphines, cattle, sheep, and goats are gregarious and not territorial. In these species, males must gain absolute dominance over all other males, and fights are not confined to territories. Males, therefore, spend years in body growth. Most bovids are diurnal, although
4374-647: The family are herbivorous , but most duikers are omnivorous . Like other ruminants, bovids have four-chambered stomachs, which allow them to digest plant material, such as grass , that cannot be used by many other animals. Ruminants (and some others like kangaroos , rabbits , and termites ) are able to use micro-organisms living in their guts to break down cellulose by fermentation . The bovids have various methods of social organisation and social behaviour, which are classified into solitary and gregarious behaviour. Further, these types may each be divided into territorial and nonterritorial behaviour. Small bovids such as
4455-501: The ground. The bovids show great variation in size: the gaur can weigh more than 1,500 kg (3,300 lb), and stand 2.2 m (87 in) high at the shoulder. The royal antelope , in sharp contrast, is only 25 cm (9.8 in) tall and weighs at most 3 kg (6.6 lb). The klipspringer , another small antelope, stands 45–60 cm (18–24 in) at the shoulder and weighs just 10–20 kg (22–44 lb). Differences occur in pelage colouration, ranging from
4536-482: The klipspringer, oribi , and steenbok are generally solitary and territorial. They hold small territories into which other members of the species are not allowed to enter. These antelopes form monogamous pairs. Many species such as the dik-dik use pheromone secretions from the preorbital glands and sometimes dung, as well, to mark their territories. The offspring disperse at the time of adolescence, and males must acquire territories prior to mating. The bushbuck
4617-552: The latter are specially adapted to arid areas. Members of Caprinae, being flexible feeders, forage even in areas with low productivity. Tribes Alcelaphini, Hippotragini, and Reduncini have high proportions of monocots in their diets. On the contrary, Tragelaphini and Neotragini (with the exception of Ourebia ) feed extensively on dicots . No conspicuous relationship exists between body size and consumption of monocots. Phylogenetic In biology , phylogenetics ( / ˌ f aɪ l oʊ dʒ ə ˈ n ɛ t ɪ k s , - l ə -/ )
4698-475: The majority of models, sampling fewer taxon with more sites per taxon demonstrated higher accuracy. Generally, with the alignment of a relatively equal number of total nucleotide sites, sampling more genes per taxon has higher bootstrapping replicability than sampling more taxa. However, unbalanced datasets within genomic databases make increasing the gene comparison per taxon in uncommonly sampled organisms increasingly difficult. The term "phylogeny" derives from
4779-618: The mid-20th century but now largely obsolete, used distance matrix -based methods to construct trees based on overall similarity in morphology or similar observable traits (i.e. in the phenotype or the overall similarity of DNA , not the DNA sequence ), which was often assumed to approximate phylogenetic relationships. Prior to 1950, phylogenetic inferences were generally presented as narrative scenarios. Such methods are often ambiguous and lack explicit criteria for evaluating alternative hypotheses. In phylogenetic analysis, taxon sampling selects
4860-494: The middle Miocene, and seem to have been replaced by other bovids and cervids in Eurasia. The earliest fossils of the antilopines are from the middle Miocene, though studies show the existence of the subfamily from the early Miocene. Speciation occurred in the tribe Antilopini during the middle or upper Miocene, mainly in Eurasia. Tribe Neotragini seems to have appeared in Africa by the end of Miocene, and had become widespread by
4941-431: The monogamous duikers and other small antelopes, whereas in the polygynous, they are large and elaborately formed (for example in a spiral structure, as in the giant eland ). Thus, to some extent, horns depict the degree of competition among males in a species. However, the presence of horns in females is likely due to natural selection . The horns of females are usually smaller than those of males, and are sometimes of
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#17328582978705022-413: The opponent's head rather than its body. The S-shaped horns, such as those on the impala , have various sections that help in ramming, holding, and stabbing. Serious fights leading to injury are rare. Most bovids alternately feed and ruminate throughout the day. While those that feed on concentrate feed and digest in short intervals, the roughage feeders take longer intervals. Only small species such as
5103-429: The opponents move in a circular manner to unlock them. Muskoxen will ram into each other at high speeds. As a rule, only two bovids of equal build and level of defence engage in a fight, which is intended to determine the superior of the two. Individuals that are evidently inferior to others would rather flee than fight; for example, immature males do not fight with the mature bulls. Generally, bovids direct their attacks on
5184-442: The oval or pointed ears, a distinct neck and limbs, and a tail varying in length and bushiness among the species. Most bovids exhibit sexual dimorphism , with males usually larger as well as heavier than females. Sexual dimorphism is more prominent in medium- to large-sized bovids. All bovids have four toes on each foot – they walk on the central two (the hooves ), while the outer two (the dewclaws ) are much smaller and rarely touch
5265-528: The phylogenetic history of a species cannot be read directly from its ontogeny, as Haeckel thought would be possible, but characters from ontogeny can be (and have been) used as data for phylogenetic analyses; the more closely related two species are, the more apomorphies their embryos share. One use of phylogenetic analysis involves the pharmacological examination of closely related groups of organisms. Advances in cladistics analysis through faster computer programs and improved molecular techniques have increased
5346-510: The precision of phylogenetic determination, allowing for the identification of species with pharmacological potential. Historically, phylogenetic screens for pharmacological purposes were used in a basic manner, such as studying the Apocynaceae family of plants, which includes alkaloid-producing species like Catharanthus , known for producing vincristine , an antileukemia drug. Modern techniques now enable researchers to study close relatives of
5427-498: The predator has been seen, and that the stotting individual is strong and not worth chasing. In the mating season, rutting males bellow to make their presence known to females. Muskoxen roar during male-male fights, and male saigas force air through their noses, producing a roar to deter rival males and attract females. Mothers also use vocal communication to locate their calves if they get separated. During fights over dominance, males tend to display themselves in an erect posture with
5508-415: The progression of the disease and during treatment, using whole genome sequencing techniques. The evolutionary processes behind cancer progression are quite different from those in most species and are important to phylogenetic inference; these differences manifest in several areas: the types of aberrations that occur, the rates of mutation , the high heterogeneity (variability) of tumor cell subclones, and
5589-418: The properties of pathogen phylogenies. Phylodynamics uses theoretical models to compare predicted branch lengths with actual branch lengths in phylogenies to infer transmission patterns. Additionally, coalescent theory , which describes probability distributions on trees based on population size, has been adapted for epidemiological purposes. Another source of information within phylogenies that has been explored
5670-477: The recognition of Peleinae and Pantholopinae , comprising the genera Pelea and Pantholops respectively, as subfamilies . In 2000, American biologist George Schaller and palaeontologist Elisabeth Vrba suggested the inclusion of Pelea in Reduncinae , though the grey rhebok, the sole species of Pelea , is highly different from kobs and reduncines in morphology. Pantholops , earlier classified in
5751-543: The relationship between two variables in pathogen transmission analysis, such as the number of infected individuals and the time since infection. These plots can help identify trends and patterns, such as whether the spread of the pathogen is increasing or decreasing over time, and can highlight potential transmission routes or super-spreader events. Box plots displaying the range, median, quartiles, and potential outliers datasets can also be valuable for analyzing pathogen transmission data, helping to identify important features in
5832-410: The relationships between several of the languages in a timeline, as well as the similarity between words and word order. There are three types of criticisms about using phylogenetics in philology, the first arguing that languages and species are different entities, therefore you can not use the same methods to study both. The second being how phylogenetic methods are being applied to linguistic data. And
5913-575: The relationships between viruses e.g., all viruses are descendants of Virus A. HIV forensics uses phylogenetic analysis to track the differences in HIV genes and determine the relatedness of two samples. Phylogenetic analysis has been used in criminal trials to exonerate or hold individuals. HIV forensics does have its limitations, i.e., it cannot be the sole proof of transmission between individuals and phylogenetic analysis which shows transmission relatedness does not indicate direction of transmission. Taxonomy
5994-485: The same useful traits. The phylogenetic tree shows which species of fish have an origin of venom, and related fish they may contain the trait. Using this approach in studying venomous fish, biologists are able to identify the fish species that may be venomous. Biologist have used this approach in many species such as snakes and lizards. In forensic science , phylogenetic tools are useful to assess DNA evidence for court cases. The simple phylogenetic tree of viruses A-E shows
6075-481: The shape of phylogenetic trees, as illustrated in Fig. 1. Researchers have analyzed the structural characteristics of phylogenetic trees generated from simulated bacterial genome evolution across multiple types of contact networks. By examining simple topological properties of these trees, researchers can classify them into chain-like, homogeneous, or super-spreading dynamics, revealing transmission patterns. These properties form
6156-463: The strongly contrasting patterns helping to delay recognition by predators. However, all the Hippotraginae (including the gemsbok) have pale bodies and faces with conspicuous markings. The zoologist Tim Caro describes this as difficult to explain, but given that the species are diurnal, he suggests that the markings may function in communication. Strongly contrasting leg colouration is common only in
6237-709: The subfamily Tethytraginae , which contains Tethytragus (mid- Miocene ). In 1992, Alan W . Gentry of the Natural History Museum, London divided the eight major subfamilies of Bovidae into two major clades on the basis of their evolutionary history: the Boodontia, which comprised only the Bovinae, and the Aegodontia, which consisted of the rest of the subfamilies. Boodonts have somewhat primitive teeth, resembling those of oxen , whereas aegodonts have more advanced teeth like those of goats. A controversy exists about
6318-405: The third and fourth metapodials are combined into the cannon bone . The ulna and fibula are reduced, and fused with the radius and tibia, respectively. Long scapulae are present, whereas the clavicles are absent. Being ruminants , the stomach is composed of four chambers: the rumen (80%), the omasum , the reticulum , and the abomasum . The ciliates and bacteria of the rumen ferment
6399-421: The third, discusses the types of data that is being used to construct the trees. Bayesian phylogenetic methods, which are sensitive to how treelike the data is, allow for the reconstruction of relationships among languages, locally and globally. The main two reasons for the use of Bayesian phylogenetics are that (1) diverse scenarios can be included in calculations and (2) the output is a sample of trees and not
6480-493: Was given by the British zoologist John Edward Gray in 1821. The word "Bovidae" is the combination of the prefix bov- (originating from Latin bos , "ox", through Late Latin bovinus ) and the suffix -idae . The family Bovidae is placed in the order Artiodactyla (which includes the even-toed ungulates ). It includes 143 extant species, accounting for nearly 55% of the ungulates , and 300 known extinct species. Until
6561-605: Was removed, and both groups expanded into the territory of the other. The tribes Bovini and Tragelaphini diverged in the early Miocene. Bovids are known to have reached the Americas in the Pleistocene by crossing the Bering land bridge . The present genera of Alcelaphinae appeared in the Pliocene . The extinct Alcelaphine genus Paramularius , which was the same in size as the hartebeest,
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