@article{macfadden1976cladistic,
    author = "MacFadden, Bruce J.",
    title = "Cladistic Analysis of Primitive Equids, with Notes on Other Perissodactyls",
    year = "1976",
    journal = "Systematic Zoology",
    url = "https://doi.org/10.2307/2412774",
    doi = "10.2307/2412774",
    number = "1",
    openalex = "W2124811114",
    pages = "1",
    volume = "25",
    references = "doi101086394242, doi101111j109636421952tb00784x, doi1023072405671, doi1023072412606, doi1023073037993, doi105281zenodo18028696, doi105962bhltitle156460, doi107312simp92414, openalexw1988829823, openalexw3135630760"
}

@misc{macfadden1976cladistic2,
    author = "MacFadden, B. J",
    title = "Cladistic analysis of primitive equids, with notes on other perissodactyls",
    year = "1976",
    howpublished = "Systematic Zoology, v. 25, p. 1-15",
    note = "talkorigins\_source = {true}; raw\_reference = {MacFadden, B. J., 1976, Cladistic analysis of primitive equids, with notes on other perissodactyls: Systematic Zoology, v. 25, p. 1-15.}"
}

@misc{gould1977the1,
    author = "Gould, S. J. and Raup, D. M. and Sepkoski, J. J. and Schopf, T. J. M. and Simberloff, D. S",
    title = "The shape of evolution",
    year = "1977",
    howpublished = "A comparison of real and random clades: Paleobiology, v. 3, p. 23-40",
    note = "talkorigins\_source = {true}; raw\_reference = {Gould, S. J., Raup, D. M., Sepkoski, J. J., Schopf, T. J. M., and Simberloff, D. S., 1977, The shape of evolution: A comparison of real and random clades: Paleobiology, v. 3, p. 23-40.}"
}

@article{doi1023072413039,
    author = "Brooks, Daniel R. and Nelson, Gareth and Platnick, Norman I.",
    title = "Systematics and Biogeography: Cladistics and Vicariance.",
    year = "1982",
    journal = "Systematic Zoology",
    url = "https://doi.org/10.2307/2413039",
    doi = "10.2307/2413039",
    openalex = "W2321544600"
}

@article{benton1990the,
    author = "Benton, Michael J.",
    title = "The evolution of perissodactyls",
    year = "1990",
    journal = "Trends in Ecology \& Evolution",
    url = "https://doi.org/10.1016/0169-5347(90)90187-i",
    doi = "10.1016/0169-5347(90)90187-i",
    number = "10",
    openalex = "W2094377919",
    pages = "347",
    volume = "5",
    references = "doi1010160169534788900468, doi1010160169534788901048, doi101111j109600311986tb00463x"
}

@article{crossref1990the,
    title = "The Evolution of perissodactyls",
    year = "1990",
    journal = "Choice Reviews Online",
    url = "https://doi.org/10.5860/choice.27-5770",
    doi = "10.5860/choice.27-5770",
    number = "10",
    openalex = "W116621164",
    pages = "27-5770-27-5770",
    volume = "27"
}

@incollection{crossref1990transformed,
    title = "Transformed cladistics and evolution",
    year = "1990",
    booktitle = "Transformed Cladistics, Taxonomy and Evolution",
    url = "https://doi.org/10.1017/cbo9780511525759.008",
    doi = "10.1017/cbo9780511525759.008",
    openalex = "W2490755409",
    pages = "160-184"
}

@article{doi101111j109600311991tb00045x,
    author = "de Pinna, Mário C. C.",
    title = "CONCEPTS AND TESTS OF HOMOLOGY IN THE CLADISTIC PARADIGM",
    year = "1991",
    journal = "Cladistics",
    abstract = "Abstract— Logical equivalence between the notions of homology and synapomorphy is reviewed and supported. So‐called transformational homology embodies two distinct logical components, one related to comparisons among different organisms and the other restricted to comparisons within the same organism. The former is essentially hierarchical in nature, thus being in fact a less obvious form of taxic homology. The latter is logically equivalent to so‐called serial homology in a broad sense (including homonomy, mass homology or iterative homology). Of three tests of homology proposed to date (similarity, conjunction and congruence) only congruence serves as a test in the strict sense. Similarity stands at a basic level in homology propositions, being the source of the homology conjecture in the first place. Conjunction is unquestionably an indicator of non‐homology, but it is not specific about the pairwise comparison where non‐homology is present, and depends on a specific scheme of relationship in order to refute a hypothesis of homology. The congruence test has been previously seen as an application of compatibility analysis. However, congruence is more appropriately seen as an expression of strict parsimony analysis. A general theoretical solution is proposed to determine evolution of characters with ambiguous distributions, based on the notion of maximization of homology propositions. According to that notion, ambiguous character‐state distributions should be resolved by an optimization that maximizes reversals relative to parallelisms. Notions of homology in morphology and molecular biology are essentially the same. The present tendency to adopt different terminologies for the two sources of data should be avoided, in order not to obscure the fundamental uniformity of the concept of homology in comparative biology. “A similar hierarchy is found both in ‘structures’ and in ‘functions’. In the last resort, structure (i.e. order of parts) and function (order of processes) may be the very same thing […].” L. von Bertalanlfy “[…] it is the fact that certain criteria enable us to match parts of things consistently which suggests that mechanisms of certain kinds must have been involved in their origin.” N. Jardine and C. Jardine",
    url = "https://doi.org/10.1111/j.1096-0031.1991.tb00045.x",
    doi = "10.1111/j.1096-0031.1991.tb00045.x",
    openalex = "W2142398288",
    references = "doi101007bf02603120, doi101093sysbio19183, doi101093sysbio242233, doi101126science7280687, doi101146annureven10010165000525, doi1023072411550, doi1023072412028, doi1023072412448, doi1023072413454, doi1023072806339, doi1023072992444, doi107312crac92306005, openalexw1988829823, openalexw3184837389"
}

@article{doi101093genetics1322619,
    author = "Templeton, Alan R. and Crandall, Keith A. and Sing, Charles F.",
    title = "A cladistic analysis of phenotypic associations with haplotypes inferred from restriction endonuclease mapping and DNA sequence data. III. Cladogram estimation.",
    year = "1992",
    journal = "Genetics",
    abstract = "We previously developed a cladistic approach to identify subsets of haplotypes defined by restriction endonuclease mapping or DNA sequencing that are associated with significant phenotypic deviations. Our approach was limited to segments of DNA in which little recombination occurs. In such cases, a cladogram can be constructed from the restriction site or sequence data that represents the evolutionary steps that interrelate the observed haplotypes. The cladogram is used to define a nested statistical design to identify mutational steps associated with significant phenotypic deviations. The central assumption behind this strategy is that any undetected mutation causing a phenotypic effect is embedded within the same evolutionary history that is represented by the cladogram. The power of this approach depends upon the confidence one has in the particular cladogram used to draw inferences. In this paper, we present a strategy for estimating the set of cladograms that are consistent with a particular sample of either restriction site or nucleotide sequence data and that includes the possibility of recombination. We first evaluate the limits of parsimony in constructing cladograms. Once these limits have been determined, we construct the set of parsimonious and nonparsimonious cladograms that is consistent with these limits. Our estimation procedure also identifies haplotypes that are candidates for being products of recombination. If recombination is extensive, our algorithm subdivides the DNA region into two or more subsections, each having little or no internal recombination. We apply this estimation procedure to three data sets to illustrate varying degrees of cladogram ambiguity and recombination.",
    url = "https://doi.org/10.1093/genetics/132.2.619",
    doi = "10.1093/genetics/132.2.619",
    openalex = "W1901627773",
    references = "doi101007bf01734101, doi101111j155856461983tb05533x, doi101146annurevge22120188002513"
}

@article{doi101111j109600311993tb00226x,
    author = "Thiele, Kevin R.",
    title = "THE HOLY GRAIL OF THE PERFECT CHARACTER: THE CLADISTIC TREATMENT OF MORPHOMETRIC DATA",
    year = "1993",
    journal = "Cladistics",
    abstract = {Abstract- Data scored for cladistic analyses may be quantitative or qualitative, continuous or discrete, and show overlapping or non-overlapping values between taxa. Quantitative and qualitative are modes of expression of data, while continuous or discrete refer to properties of the set of numbers that express the data; both these pairs of terms have been confused with overlapping and non-overlapping. The degree of overlap of values between taxa is often used to filter characters in cladistic analyses: if a minimum amount of overlap is exceeded, or a minimum amount of disjunction not reached, characters are rejected as "not cladistic". However, this rests on a confusion between features of taxa and features of individual organisms (attributes). Cladistic characters are features of taxa, and comprise frequency distributions of attribute values over individuals of a taxon. Cladistic characters logically cannot overlap, although taxa may have overlapping attribute values. Thus, a priori rejection of characters that have overlapping attribute values is non-sensical. Such data may still be rejected from consideration for cladistic analysis if it could be demonstrated that they contain little recoverable phylogenetic signal. Few published analyses have empirically tested this. An analysis of overlapping morphometric data from three series of Banksia suggests that, at least in these cases, they map phylogeny almost as accurately as more conventional, qualitative morphological data. While more such tests are required, morphometric data should not be rejected a priori from cladistic analyses.},
    url = "https://doi.org/10.1111/j.1096-0031.1993.tb00226.x",
    doi = "10.1111/j.1096-0031.1993.tb00226.x",
    openalex = "W2077186234",
    references = "doi1023072412452"
}

@book{openalexw2094558211,
    author = "Bremer, Kåre and Anderberg, Arne A.",
    title = "Asteraceae: Cladistics and Classification",
    year = "1994",
    abstract = "Using the technique of cladistics, the author and his collaborators have been able to reconstruct the phylogeny within the Asteraceae (Compositae) family.",
    url = "https://openalex.org/W2094558211",
    openalex = "W2094558211"
}

@article{doi101111j146364091997tb00412x,
    author = "Rouse, Greg W. and Fauchald, Kristian",
    title = "Cladistics and polychaetes",
    year = "1997",
    journal = "Zoologica Scripta",
    abstract = "A series of cladistic analyses assesses the status and membership of the taxon Polychaeta. The available literature, and a review by Fauchald \& Rouse (1997), on the 80 accepted families of the Polychaeta are used to develop characters and data matrices. As well as the polychaete families, non‐polychaete taxa, such as the Echiura, Euarthropoda, Onychophora, Pogonophora (as Frenulata and Vestimentifera), Clitellata, Aeolosomatidae and Potamodrilidae, are included in the analyses. All trees are rooted using the Sipuncula as outgroup. Characters are based on features (where present) such as the prostomium, peristomium, antennae, palps, nuchal organs, parapodia, stomodaeum, segmental organ structure and distribution, circulation and chaetae. A number of analyses are performed, involving different ways of coding and weighting the characters, as well as the number of taxa included. Transformation series are provided for several of these analyses. One of the analyses is chosen to provide a new classification. The Annelida is found to be monophyletic, though weakly supported, and comprises the Clitellata and Polychaeta. The Polychaeta is monophyletic only if taxa such as the Pogonophora, Aeolosomatidae and Potamodrilidae are included and is also weakly supported. The Pogonophora is reduced to the rank of family within the Polychaeta and reverts to the name Siboglinidae Caullery, 1914. The new classification does not use Linnaean categories, and the Polychaeta comprises two clades, the Scolecida and Palpata. The Palpata has the clades Aciculata and Canalipalpata. The Aciculata contains the Phyllodocida and Eunicida. The Canalipalpata has three clades; the Sabellida (including the Siboglinidae) Spionida and Terebellida. The position of a number of families requires further investigation.",
    url = "https://doi.org/10.1111/j.1463-6409.1997.tb00412.x",
    doi = "10.1111/j.1463-6409.1997.tb00412.x",
    openalex = "W2099988673",
    references = "doi101007978140206754912413, doi1010160305197885900559, doi101093oso97801985464120010001, doi101111j109600311994tb00179x, doi101111j109600311995tb00092x, doi101111j146364091997tb00411x, doi101111j1469185x1974tb01572x, doi101111j1469185x1988tb00631x, doi101111j155856461988tb02497x, doi1023072408870, doi1023072412182, doi1023072413134, doi105860choice295104, openalexw1575297980, openalexw1809736813, openalexw659399033"
}

@book{openalexw634659594,
    author = "Kitching, Ian J.",
    title = "Cladistics: The Theory and Practice of Parsimony Analysis",
    year = "1998",
    abstract = {"Systematics underpins all of biology. Cladistics is a method of systematic classification that aims to reconstruct genealogies based on common ancestry, thus revealing the phylogenetic relationships between taxa. Its applications vary from linguistic analysis to the study of conservation and biodiversity, and it has become a method of choice for comparative studies in all fields of biology." "For all students interested in the systematic relationships among organisms, this book provides an integrated, state-of-the-art account of the techniques and methods of modern cladistics, and how to put them into practice."--BOOK JACKET.},
    url = "https://openalex.org/W634659594",
    openalex = "W634659594"
}

@article{doi101111j109600311999tb00270x,
    author = "Holbrook, Luke",
    title = "The Phylogeny and Classification of Tapiromorph Perissodactyls (Mammalia)",
    year = "1999",
    journal = "Cladistics",
    abstract = "Despite an excellent fossil record, the phylogeny of Perissodactyla is not well understood, in terms of both the relationships within Perissodactyla and the position of the Perissodactyla among the orders of mammals. This paper provides a phylogenetic analysis of one major perissodactyl lineage, the Tapiromorpha. This analysis combines a more comprehensive sampling of characters and taxa with rigorous tree‐searching methods to create a new hypothesis of tapiromorph relationships. The phylogeny of tapiromorph perissodactyls is analyzed using 45 characters of the skull, postcranial skeleton, and dentition scored for 29 taxa, including three nontapiromorph outgroups. Phylogenetic taxonomic definitions are constructed for suprageneric taxa. According to the results of this analysis, the Chalicotherioidea cannot be unequivocally assigned to the Tapiromorpha, nor can Homogalax or Cardiolophus. Isectolophus, Tapiroidea, and Rhinocerotoidea are unequivocal members of the Tapiromorpha. Heptodon is included in a monophyletic Tapiroidea. Amynodontid rhinocerotoids come out as the sister group to rhinocerotids, and indricotheres do not fall within the Hyracodontidae. The results of this study provide further arguments that tapiromorphs (and putative tapiromorphs) may be important for understanding the ancestral morphology of Perissodactyla.",
    url = "https://doi.org/10.1111/j.1096-0031.1999.tb00270.x",
    doi = "10.1111/j.1096-0031.1999.tb00270.x",
    openalex = "W4242212312",
    references = "doi10100797814684216682, doi101111j109600311993tb00234x, doi101111j109636421994tb00311x, doi101144gsljgs1848004010221, doi1023071375443, doi1023072992353, doi105281zenodo18028457, doi105281zenodo18028696, doi105860choice355657, doi105860choice392183, macfadden1976cladistic, openalexw638862129"
}

@article{doi101006jasc20010681,
    author = "O’Brien, Michael J. and Darwent, John and Lyman, R. Lee",
    title = "Cladistics Is Useful for Reconstructing Archaeological Phylogenies: Palaeoindian Points from the Southeastern United States",
    year = "2001",
    journal = "Journal of Archaeological Science",
    url = "https://doi.org/10.1006/jasc.2001.0681",
    doi = "10.1006/jasc.2001.0681",
    openalex = "W1973175607",
    references = "doi101017s0094837300005224, doi101086200289, doi101093auk1002507, doi101146annureven10010165000525, doi101722611310, doi1023071367778, doi1023071377078, doi104324978020376680411, doi105962bhltitle59991, doi105962bhltitle68064, openalexw1550375751, openalexw1988829823, openalexw3135630760, openalexw634659594"
}

@article{doi1012060003008220023660001aitrou20co2,
    author = "Solounias, Nikos and Semprebon, Gina M.",
    title = "Advances in the Reconstruction of Ungulate Ecomorphology with Application to Early Fossil Equids",
    year = "2002",
    journal = "American Museum Novitates",
    abstract = "A new and greatly simplified methodology for the assessment of the dietary adaptations of living and fossil taxa has been developed which allows for microwear scar topography to be accurately analyzed at low magnification (35×) using a standard stereomicroscope. In addition to the traditional scratch and pit numbers, we introduce four qualitative variables: scratch texture, cross scratches, large pits, and gouges, which provide finer subdivisions within the basic dietary categories. A large extant comparative ungulate microwear database (809 individuals; 50 species) is presented and interpreted to elucidate the diets of extant ungulates. We distinguish three major trophic phases in extant ungulates: traditional browsers and grazers, two phases represented by only a few species, and a browsing-grazing transitional phase where most species fall, including all mixed feeders. There are two types of mixed feeders: seasonal or regional mixed feeders and meal-by-meal mixed feeders. Some species have results that separate them from traditional members of their trophic group; i.e., browsers, grazers, and mixed feeders. Duikers are unique in spanning almost the entire dietary spectrum. Okapia, Tapirus, Tragulus, and Moschus species have wear similar to duikers. Proboscideans fall in the browsing-grazing transitional phase, as do the two suids studied. The latter differ from each other by their degree of rooting.Archaic fossil equids spanning the supposed browsing-grazing transition were compared to extant ungulates. Two major clusters are discerned: (1) Hyracotherium has microwear most similar to that of the duiker Cephalopus silvicultor and was a fruit/seed eating browser. (2) Mesohippus spp., M. bairdii, Mesohippus hypostylus, Meso-Miohippus (a transitional form larger than M. bairdii), Parahippus spp., and Merychippus insignis differ from Hyracotherium and are most similar to the extant Cervus canadensis. Group (2) is characterized by fine scratches which are the result of C3 grazing, an initial phase of grazing in equids which most likely did not occur in open habitats. Finer differentiation of group (2) diets shows a dietary change in the expected direction (toward the incorporation of more grass in the diet) and follows the expected evolutionary transition from the Eocene to the Oligocene and early Miocene. Consequently, these equid taxa are reconstructed here as mixed feeders grazing on forest C3 grasses. The finer dietary differentiation shows a progressive decrease in the number of scratches and pits. Mesohippus has the most pits and scratches, followed by Parahippus, and then Merychippus (which has the least). The taxon incorporating the most grass into its dietary regime in this array is Merychippus. In Mesohippus-Parahippus versus Merychippus, differences in tooth morphology are major but microwear differences are slight.",
    url = "https://doi.org/10.1206/0003-0082(2002)366<0001:aitrou>2.0.co;2",
    doi = "10.1206/0003-0082(2002)366<0001:aitrou>2.0.co;2",
    openalex = "W2169973548",
    references = "doi101007bf00378733, doi101086394242, doi101111j1469185x1982tb00370x, doi101111j1469185x1988tb00630x"
}

@article{doi10166600948373200632236eohiet20co2,
    author = "Strömberg, Caroline A. E.",
    title = "Evolution of hypsodonty in equids: testing a hypothesis of adaptation",
    year = "2006",
    journal = "Paleobiology",
    abstract = "Abstract The independent acquisition of high-crowned cheek teeth (hypsodonty) in several ungulate lineages (e.g., camels, equids, rhinoceroses) in the early to middle Miocene of North America has classically been used as an indication that savanna vegetation spread during this time. Implicit in this interpretation is the untested assumption that hypsodonty was an evolutionary response to feeding in open habitats, either due to a change in food source (from browse to graze) or to increased incorporation of airborne grit in the diet. I examined the adaptive explanation for hypsodonty in equids using criteria pertaining to process and pattern of adaptations set up in the comparative-methods literature. Specifically, I tested whether hypsodonty appeared coincident with or just after the spread of open, grass-dominated habitats in the Great Plains of North America. Phytolith (plant opal) analysis of 99 phytolith assemblages extracted from sediment samples from Montana/Idaho, Nebraska/Wyoming, and Colorado were used to establish the first continuous record of middle Eocene–late Miocene vegetation change in the northern to Central Great Plains. This record was compared with the fossil record of equids from the same area in a phylogenetic framework. The study showed that habitats dominated by C3 grasses were established in the Central Great Plains by early late Arikareean (≥21.9 Ma), at least 4 Myr prior to the emergence of hypsodont equids (Equinae). Nevertheless, the adaptive hypothesis for hypsodonty in equids could not be rejected, because the earliest savanna-woodlands roughly co-occurred with members of the grade constituting the closest outgroups to Equinae (“Parahippus”) showing mesodont dentition. Explanations for the slow evolution of full hypsodonty may include weak and changing selection pressures and/or phylogenetic inertia. These results suggest that care should be taken when using functional morphology alone to reconstruct habitat change.",
    url = "https://doi.org/10.1666/0094-8373(2006)32[236:eohiet]2.0.co;2",
    doi = "10.1666/0094-8373(2006)32[236:eohiet]2.0.co;2",
    openalex = "W2176339957",
    references = "crossref1990the, doi10100703064746897, doi101017s0094837300004310, doi101017s009483730001157x, doi101086394242, doi101093icb232347, doi101111j155856461997tb01457x, doi101146annurevecolsys311367, doi1015159781400820108, doi1023072576242, doi104159harvard9780674865327, doi105860choice295104, doi105860choice396411, macfadden1976cladistic"
}

@article{andersen2009some,
    author = "Andersen, N. Møller",
    title = "Some principles and methods of cladistic analysis with notes on the uses of cladistics in classification and biogeography",
    year = "2009",
    journal = "Journal of Zoological Systematics and Evolutionary Research",
    url = "https://doi.org/10.1111/j.1439-0469.1978.tb00679.x",
    doi = "10.1111/j.1439-0469.1978.tb00679.x",
    number = "4",
    openalex = "W2152249538",
    pages = "242-255",
    volume = "16",
    references = "doi101093sysbio20163, doi101111j155856461965tb01722x, doi101146annureven10010165000525, doi1023071793007, doi1023072411550, doi1023072412182, doi1023072412452, doi1023073151168, doi107312simp93764"
}

@article{doi101111j143904691979tb00714x,
    author = "Weygoldt, Peter",
    title = "Cladistic versus phenetic classification - an endless debate?",
    year = "2009",
    journal = "Journal of Zoological Systematics \& Evolutionary Research",
    abstract = "Summary Both types of evolution events, splitting and anagenesis, cannot be combined within one classification. Only a cladisti classification is objective and testable. An evolutionary classification remains subjective and ambiguous but in spite of this contains much valuable information. Therefore, both types of classification should be superimposed. Zusammenfassung Kladistische oder evolutionäre Klassifikation - eine endlose Debatte? In der immer mehr mit philosophischen Argumenten geführten Debatte über kladistische oder evo-lutionäre Klassifikation in “Systematic Zoology” wird immer wieder gefordert, daß eine Klassifikation beide Evolutionsereignisse, Aufspaltung und Anagenese, widerspiegeln sollte. Es wird gezeigt, daß das unmóglich ist und daß nur eine kladistische Klassifikation objektiv und falsifizierbar ist, daß aber eine notwendigerweise mehr oder wenier subjektive evolutionäre Klassifikation auch so viel Information enthält, daß man beide Klassifikationen nebeneinanderstellen sollte.",
    url = "https://doi.org/10.1111/j.1439-0469.1979.tb00714.x",
    doi = "10.1111/j.1439-0469.1979.tb00714.x",
    openalex = "W1971833370",
    references = "andersen2009some, doi101146annureven10010165000525, doi1023072412606, doi1023072412883, doi1023072412889, doi1023072412890, doi1023072412891"
}

@article{doi104202app20100021,
    author = "von Koenigswald, Wighart and Holbrook, Luke and Rose, Kenneth D.",
    title = "Diversity and Evolution of Hunter-Schreger Band Configuration in Tooth Enamel of Perissodactyl Mammals",
    year = "2010",
    journal = "Acta Palaeontologica Polonica",
    abstract = "ration in tooth enamel of perissodactyl mammals. Acta Palaeontologica Polonica 56 (1): 11–32. Four different Hunter−Schreger Band (HSB) configurations were observed in the teeth of fossil and extant Perissodactyla. This variability exceeds that observed in Artiodactyla or Proboscidea. The four HSB configurations represent two different evolutionary pathways. Transverse HSB found in many mammalian taxa outside the Perissodactyla represents the most primitive HSB configuration. It occurs in several primitive perissodactyl families and is retained in Palaeotheriidae and ex− tant Equidae. Curved HSB evolved from transverse HSB and occurs in Tapiridae, Helaletidae, and Lophiodontidae, as well as in Ancylopoda and Titanotheriomorpha. This likely indicates independent evolution of curved HSB in two or more lin− eages, but the number of instances of parallelism of this configuration is obscured by uncertainty in the relationships among these taxa and by a lack of data for some important basal taxa. A second evolutionary pathway leads from transverse HSB via compound HSB to vertical HSB. Compound HSB were detected in Hyrachyidae, Deperetellidae, and the early rhinocerotid Uintaceras. Vertical HSB configuration characterizes the molar dentition of other Rhinocerotidae, Hyra− codontidae, Indricotheriidae, and Amynodontidae. Often, the incisors of rhinocerotids retain traces of compound HSB. Thus the HSB configuration reflects phylogenetic relationships to some degree. The selective value of the modified HSB configu− rations is interpreted functionally as a mechanism to reduce abrasion during mastication, assuming that the perpendicular in− tersection of prisms with the actual grinding surfaces resists wear better than prisms running parallel to the occlusal surface.",
    url = "https://doi.org/10.4202/app.2010.0021",
    doi = "10.4202/app.2010.0021",
    openalex = "W2071964024",
    references = "doi101111j109600311999tb00270x"
}

@article{doi101111j2041210x201100169x,
    author = "Revell, Liam J.",
    title = "phytools: an R package for phylogenetic comparative biology (and other things)",
    year = "2011",
    journal = "Methods in Ecology and Evolution",
    abstract = "Summary 1. Here, I present a new, multifunctional phylogenetics package, phytools, for the R statistical computing environment. 2. The focus of the package is on methods for phylogenetic comparative biology; however, it also includes tools for tree inference, phylogeny input/output, plotting, manipulation and several other tasks. 3. I describe and tabulate the major methods implemented in phytools, and in addition provide some demonstration of its use in the form of two illustrative examples. 4. Finally, I conclude by briefly describing an active web‐log that I use to document present and future developments for phytools. I also note other web resources for phylogenetics in the R computational environment.",
    url = "https://doi.org/10.1111/j.2041-210x.2011.00169.x",
    doi = "10.1111/j.2041-210x.2011.00169.x",
    openalex = "W1605984840",
    references = "doi1010179781316276259010, doi10103844766, doi10108010635150802302427, doi101086284325, doi101086343873, doi101086383584, doi101086660020, doi101093bioinformaticsbtg412, doi101093bioinformaticsbtq706, doi101093oso97801985464120010001, doi101111j001438202003tb00285x, doi101111j15585646201001026x, doi10118614712105788, doi105860choice295104, openalexw1549853756, openalexw229097380"
}

@article{doi101371journalpone0055950,
    author = "Vilstrup, Julia T. and Seguin‐Orlando, Andaine and Stiller, Mathias and Ginolhac, Aurélien and Raghavan, Maanasa and Nielsen, Sandra C. A. and Weinstock, Jacobo and Froese, Duane and Vasiliev, Sergei K. and Ovodov, Nikolai D. and Clary, Joël and Helgen, Kristofer M. and Fleischer, Robert C. and Cooper, Alan and Shapiro, Beth and Orlando, Ludovic",
    title = "Mitochondrial Phylogenomics of Modern and Ancient Equids",
    year = "2013",
    journal = "PLoS ONE",
    abstract = "The genus Equus is richly represented in the fossil record, yet our understanding of taxonomic relationships within this genus remains limited. To estimate the phylogenetic relationships among modern horses, zebras, asses and donkeys, we generated the first data set including complete mitochondrial sequences from all seven extant lineages within the genus Equus. Bayesian and Maximum Likelihood phylogenetic inference confirms that zebras are monophyletic within the genus, and the Plains and Grevy's zebras form a well-supported monophyletic group. Using ancient DNA techniques, we further characterize the complete mitochondrial genomes of three extinct equid lineages (the New World stilt-legged horses, NWSLH; the subgenus Sussemionus; and the Quagga, Equus quagga quagga). Comparisons with extant taxa confirm the NWSLH as being part of the caballines, and the Quagga and Plains zebras as being conspecific. However, the evolutionary relationships among the non-caballine lineages, including the now-extinct subgenus Sussemionus, remain unresolved, most likely due to extremely rapid radiation within this group. The closest living outgroups (rhinos and tapirs) were found to be too phylogenetically distant to calibrate reliable molecular clocks. Additional mitochondrial genome sequence data, including radiocarbon dated ancient equids, will be required before revisiting the exact timing of the lineage radiation leading up to modern equids, which for now were found to have possibly shared a common ancestor as far as up to 4 Million years ago (Mya).",
    url = "https://doi.org/10.1371/journal.pone.0055950",
    doi = "10.1371/journal.pone.0055950",
    openalex = "W2003372336",
    references = "doi101093sysbio293272"
}

@incollection{crossref2014cladistics,
    title = "Cladistics",
    year = "2014",
    booktitle = "CIRP Encyclopedia of Production Engineering",
    url = "https://doi.org/10.1007/978-3-642-20617-7\_100063",
    doi = "10.1007/978-3-642-20617-7\_100063",
    openalex = "W4235739240",
    pages = "194-194"
}

@article{doi101111evo12463,
    author = "Adams, Dean C.",
    title = "A METHOD FOR ASSESSING PHYLOGENETIC LEAST SQUARES MODELS FOR SHAPE AND OTHER HIGH-DIMENSIONAL MULTIVARIATE DATA",
    year = "2014",
    journal = "Evolution",
    abstract = "Studies of evolutionary correlations commonly use phylogenetic regression (i.e., independent contrasts and phylogenetic generalized least squares) to assess trait covariation in a phylogenetic context. However, while this approach is appropriate for evaluating trends in one or a few traits, it is incapable of assessing patterns in highly multivariate data, as the large number of variables relative to sample size prohibits parametric test statistics from being computed. This poses serious limitations for comparative biologists, who must either simplify how they quantify phenotypic traits, or alter the biological hypotheses they wish to examine. In this article, I propose a new statistical procedure for performing ANOVA and regression models in a phylogenetic context that can accommodate high-dimensional datasets. The approach is derived from the statistical equivalency between parametric methods using covariance matrices and methods based on distance matrices. Using simulations under Brownian motion, I show that the method displays appropriate Type I error rates and statistical power, whereas standard parametric procedures have decreasing power as data dimensionality increases. As such, the new procedure provides a useful means of assessing trait covariation across a set of taxa related by a phylogeny, enabling macroevolutionary biologists to test hypotheses of adaptation, and phenotypic change in high-dimensional datasets.",
    url = "https://doi.org/10.1111/evo.12463",
    doi = "10.1111/evo.12463",
    openalex = "W2102871571",
    references = "doi101093sysbiosyp106, doi101093sysbiosyt053, doi101111j14209101201102427x"
}

@article{bai2018the,
    author = "Bai, Bin and Wang, Yuan-Qing and Meng, Jin",
    title = "The divergence and dispersal of early perissodactyls as evidenced by early Eocene equids from Asia",
    year = "2018",
    journal = "Communications Biology",
    abstract = "The earliest perissodactyls are represented by some basal equoid fossils from Euramerica near the Paleocene/Eocene boundary. Unequivocal early equoids have yet to be reported from the early Eocene of Asia, although other groups of early perissodactyls were indeed present in Asia. Here we report the earliest Eocene Asian equid, Erihippus tingae gen. et sp. nov., based on partial specimens initially assigned to the ceratomorph Orientolophus hengdongensis, from the Hengyang Basin of Hunan Province, China. The specimens previously assigned to ‘ Propachynolophus ’ hengyangensis from the same Lingcha fauna are split and now reassigned as an ancylopod Protomoropus? hengyangensis and a brontothere Danjiangia lambdodon sp. nov. The nearly simultaneous appearance of equids, ceratomorphs, ancylopods, and brontotheres in the Hengyang Basin suggests that the four main groups of perissodactyls diverged as early as, or no later than, the beginning of the Eocene (about 56 Ma), and displayed different dispersal scenarios during the early Eocene.",
    url = "https://doi.org/10.1038/s42003-018-0116-5",
    doi = "10.1038/s42003-018-0116-5",
    number = "1",
    openalex = "W2885310723",
    volume = "1",
    references = "doi101038nature14249, doi101046j10963642200200005x, doi101073pnas0511296103, doi10108002724634199910011129, doi101098rspb20142671, doi101111j109636421994tb00311x, doi101126science1068700, doi101130spe369, doi101371journalpone0107447, doi105860choice355657, doi105860choice432801, openalexw16475780, openalexw2896296657"
}

@misc{bai2020the,
    author = "Bai, B and Wang, Y and Meng, J",
    title = "The divergence and dispersal of early perissodactyls as evidenced by Early Eocene equids from Asia [X25498] Early equids from Asia",
    year = "2020",
    booktitle = "MorphoBank datasets",
    url = "https://doi.org/10.7934/x25498",
    doi = "10.7934/x25498",
    openalex = "W2908400088"
}