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At least 991 records · Page 55Linked to original sources
PubMed2003

The nerve supply to the clavicular part of the pectoralis major muscle: an anatomical study and clinical application of the function-preserving pectoralis major island flap.

The purpose of this study was to investigate the nerve supply to the clavicular part of the pectoralis major muscle so that the innervation to this part can be maintained in the muscle-preserving pectoralis major island-flap transfer. Although methods have been described that include a limited portion of the muscle while leaving the upper parts undisturbed with an intact motor innervation, reports on anatomical studies of this nerve supply are brief. The distal distribution of the nerves, the spatial relationship to the main vascular pedicle, and the ways to preserve them during surgical procedures remain unclear. Surgically relevant features of the clavicular part of the pectoralis major muscle were studied by dissection. The nerve supply to this part was examined on 11 sides of eight formalin-fixed cadavers. Two fresh cadavers were used for dissection, intraarterial polymer injection, and application of a nerve-preserving surgical technique. In all subjects, a separate nerve innervated the clavicular and upper medial sternocostal portions of the pectoralis major muscle. This nerve arises craniomedial to the main vascular pedicle of the flap and divides into several branches. These branches run in a fascia on the deep surface of the pectoralis major muscle, superficial to the origin and distal course of the vascular pedicle. Most branches to the clavicular part end medial to the coracoid process. The course of the branches to the upper sternocostal part is more medial. Based on their anatomical findings, the authors propose a surgical technique for transfer of the pectoralis major island flap to the head and neck area through a tunnel in the deltopectoral groove, lateral to the origin of the vascular pedicle. Head and neck reconstruction was performed using this technique. The presented method is a muscle-preserving procedure that maintains maximal donor-site function and morphology.

Cadaver↗
PubMed1996

Morphology and projections of neurons in Remak's nerve of the domestic fowl revealed by intracellular injection of biocytin.

Micro-injections of biocytin were made into neurons in whole-mount preparations of Remak's nerve of the domestic fowl to visualise the morphology and projections of Remak's neurons. Remak's neurons were classified into four distinct morphological types. Remak type-I and -II neurons had a morphology resembling that of mammalian sympathetic neurons. Type-I neurons (found only in juxta-jejunal ganglia) had numerous primary dendritic processes (8-14) with large dendritic fields and extensive dendritic arborizations. Type-II neurons had 2-9 primary dendritic processes, large dendritic fields and sparse dendritic branching. These were found in similar numbers in juxta-rectal and juxta-jejunal ganglia. Remak type-III neurons were the most numerous cell type of juxta-rectal ganglia. They had small cell somata and short dendritic processes that branched infrequently. Remak type-IV neurons (found only in juxta-jejunal ganglia) had a morphology resembling that of invertebrate neurons in that they possessed a prominent long tapering axon from which most of the numerous long dendritic processes emerged. In juxta-jejunal ganglia, all type-IV and most type-I, -II and -III neurons projected orally, whereas axons of juxta-rectal neurons (types II and III) projected either orally or aborally, or projected directly into a lateral nerve bundle supplying the gut. These regional differences in neuron types and axonal projections suggest that different neural circuits exist between Remak's nerve and the small and large intestine.

Animals↗
PubMed2006

Quantitation of and superficial surgical landmarks for the anterior interosseous nerve.

OBJECT: There are scant data regarding the anterior interosseous nerve (AIN) in the neurosurgical literature. In the current study the authors attempt to provide easily identifiable superficial osseous landmarks for the identification of the AIN. METHODS: The AIN in 20 upper extremities obtained in adult cadaveric specimens was dissected and quantified. Measurements were obtained between the nerve and surrounding superficial osseous landmarks. The AIN originated from the median nerve at mean distances of 5.4 cm distal to the medial epicondyle of the humerus and 21 cm proximal to the ulnar styloid process. The distance from the origin of the AIN to its branch leading to the flexor pollicis longus muscle and to the point it travels deep to the pronator quadratus (PQ) muscle measured a mean 4 and 14.4 cm, respectively. The mean distance from the AIN branch leading to the flexor pollicis longus muscle to the proximal PQ muscle was 12.1 cm, and the mean distance between this branch and the ulnar styloid process was 7.2 cm. The mean diameter of the AIN was 1.6 mm at the midforearm. CONCLUSIONS: Additional landmarks for identification of the AIN can aid the neurosurgeon in more precisely isolating this nerve and avoiding complications. Furthermore, after quantitation of this nerve, the AIN branches can be easily used for neurotization of the median and ulnar nerves, and with the aid of a transinterosseous membrane tunneling technique, passed to the posterior interosseous nerve.

Aged↗
PubMed1999

Evolution of gene expression patterns in a model of branching morphogenesis.

Branching morphogenesis of the ureteric bud in response to unknown signals from the metanephric mesenchyme gives rise to the urinary collecting system and, via inductive signals from the ureteric bud, to recruitment of nephrons from undifferentiated mesenchyme. An established cell culture model for this process employs cells of ureteric bud origin (UB) cultured in extracellular matrix and stimulated with conditioned media (BSN-CM) from a metanephric mesenchymal cell line (H. Sakurai, E. J. Barros, T. Tsukamoto, J. Barasch, and S. K. Nigam. Proc. Natl. Acad. Sci. USA 94: 6279-6284, 1997.). In the presence of BSN-CM, the UB cells form branching tubular structures reminiscent of the branching ureteric bud. The pattern of gene regulation in this model of branching morphogenesis of the kidney collecting system was investigated using high-density cDNA arrays. Software and analytical methods were developed for the quantification and clustering of genes. With the use of a computational method termed "vector analysis," genes were clustered according to the direction and magnitude of differential expression in n-dimensional log-space. Changes in gene expression in response to the BSN-CM consisted primarily of differential expression of transcription factors with previously described roles in morphogenesis, downregulation of pro-apoptotic genes accompanied by upregulation of anti-apoptotic genes, and upregulation of a small group of secreted products including growth factors, cytokines, and extracellular proteinases. Changes in expression are discussed in the context of a general model for epithelial branching morphogenesis. In addition, the cDNA arrays were used to survey expression of epithelial markers and secreted factors in UB and BSN cells, confirming the largely epithelial character of the former and largely mesenchymal character of the later. Specific morphologies (cellular processes, branching multicellular cords, etc.) were shown to correlate with the expression of different, but overlapping, genomic subsets, suggesting differences in morphogenetic mechanisms at these various steps in the evolution of branching tubules.

Animals↗
PubMed2000

Role of hyaluronan and CD44 in in vitro branching morphogenesis of ureteric bud cells.

Mutual interaction between the metanephric mesenchyme (MM) and the ureteric bud (UB) in the developing kidney leads to branching morphogenesis and the formation of the ureteric tree. A UB-derived cell line, stimulated by conditioned medium derived from an embryonic MM cell line (or, similarly, by 10% fetal calf serum), forms branching tubules under three-dimensional culture conditions (H. Sakurai et al., 1997, Proc. Natl. Acad. Sci. USA 94, 6279-6284). The formation of branching tubules in this simple in vitro system for early nephrogenesis is highly sensitive to the matrix environment, a key component of which is the glycosaminoglycan hyaluronan (HA). Consistent with this, we found that HA in the extracellular environment markedly stimulated the formation of cellular processes and multicellular cords (early steps in branching morphogenesis) and also acted as a cell survival factor. Inhibition of HA binding to the cells by addition of blocking antibodies to CD44, the principal cell surface receptor for HA, or degradation of HA by the addition of Streptomyces hyaluronidase resulted in decreased cell survival and diminished morphogenesis, indicating that the HA-CD44 axis plays a central role in in vitro branching morphogenesis. Analysis of the expression of a large number of genes displayed on a cDNA array revealed that significant changes in gene expression in cells undergoing morphogenesis in the presence of HA were limited to a small subset of genes regulating apoptosis, proliferation, and morphogenesis. This included upregulation by HA of its receptor, CD44, which was found to largely localize to the tips of branching cellular processes. In the embryonic kidney, HA was found near the developing ureteric tree and CD44 was expressed basolaterally in UB-derived structures. In addition, both UB and MM appear to express HA synthase, suggesting their ability to secrete HA. We propose that HA promotes branching morphogenesis by creating a positive feedback loop that results in (1) enhanced interaction of HA-CD44 at branching tips (possibly leading to localization of HA binding morphoregulatory factors at the tips) and (2) an activated transcriptional program favoring cell survival/proliferation and migration/morphogenesis of cells through matrix by the expression of key morphoregulatory molecules. Furthermore, since HA, hyaluronidase, and CD44 have been functionally implicated in branching morphogenesis in this model, and since HA, CD44, and HA synthase are all expressed in an appropriate spatiotemporal fashion in the developing kidney, we propose that these molecules may, together, constitute a morphoregulatory pathway that plays a key role in sequential cycles of branching morphogenesis in the UB.

Animals↗
PubMed1986

Neuropeptide-like immunoreactive cells in the retina of the larval tiger salamander: attention to the symmetry of dendritic projections.

Light microscopic immunocytochemistry was used to study the morphology of cells that showed immunoreactivity (IR) to antisera against substance P (SP), glucagon (GLU), met enkephalin (ENK), and somatostatin (SS) in the retina of the larval tiger salamander. Both vertical sections and retinal whole mounts were studied. All four antisera labeled amacrine cells in the inner nuclear layer and cells in the ganglion cell layer (GCL). GLU-IR cells had processes stratified throughout the inner plexiform layer (IPL), whereas the other three types had bistratified projections in laminae 1 and 5, with lamina 5 being broader and more dense. Two types of SS-IR amacrine cell were observed. As seen in retinal whole mount, most GLU-IR and ENK-IR amacrine cells had processes that were symmetrically distributed about the soma, whereas processes of SS- and SP-IR amacrine cells were markedly asymmetrical. The dendritic fields of SP-IR amacrine cells were selectively oriented toward the periphery of the retina in the nasal, temporal, and dorsal areas. Immunoreactive cells in the GCL had fine projections into the IPL and in addition gave rise to two large oriented processes proximal to the soma that projected in opposite directions for 100-200 microns. The oriented processes often showed further branching; they appeared to be along the radiated lines from the optic disc but did not enter it. The implications of the selectively oriented processes of SP-IR amacrine cells and cells in the GCL are discussed.

Ambystoma↗
PubMed2006

Growth conelike sensorimotor structures are characteristic features of postmigratory, premyelinating oligodendrocytes.

During development, postmigratory, premyelinating oligodendrocytes extend processes that navigate through the central nervous system (CNS) environment, where they recognize a number of extracellular cues, including axonal segments to be myelinated. Ultimately this recognition event leads to the formation of the CNS myelin sheath. However, the morphological structures and molecular mechanisms that control such oligodendroglial pathfinding are poorly understood. Here we show that postmigratory, premyelinating oligodendrocyte processes possess at their distal tips expansions that ultrastructurally resemble growth cones of postmigratory neurons and that we will refer to as OLG-growth cones. OLG-growth cones are highly motile and capable of mediating process outgrowth, retraction, and branching. In addition, they express regulators of cytoskeletal organization, GAP43 and cofilin, that are known to mediate neuronal growth cone navigation. In a choice situation, processes of postmigratory, premyelinating oligodendrocytes and their OLG-growth cones have the ability to selectively avoid a nonpermissive substrate, that is, collagen IV. Thus, our findings provide, for the first time, a detailed characterization of sensorimotor structures present at the tips of postmigratory, premyelinating oligodendrocyte processes. Furthermore, the data presented here suggest that, although the cellular mechanisms involved in growth cone steering may be similar for postmigratory neuronal and oligodendroglial cells, extracellular cues may be interpreted in a cell-type-specific fashion.

Actin Depolymerizing Factors↗
PubMed2005

Altered dendritic arborization of amygdala neurons in young adult rats orally intubated with Clitorea ternatea aqueous root extract.

Young adult (60 day old) Wistar rats of either sex were orally intubated with 50 mg/kg body weight and 100 mg/kg body weight of aqueous root extract of Clitoria ternatea (CTR) for 30 days, along with age-matched saline controls. These rats were then subjected to passive avoidance tests and the results from these studies showed a significant increase in passive avoidance learning and retention. Subsequent to the passive avoidance tests, these rats were killed by decapitation. The amygdala was processed for Golgi staining and the stained neurons were traced using a camera lucida and analysed. The results showed a significant increase in dendritic intersections, branching points and dendritic processes arising from the soma of amygdaloid neurons in CTR treated rats especially in the 100 mg/kg group of rats, compared with age-matched saline controls. This improved dendritic arborization of amygdaloid neurons correlates with the increased passive avoidance learning and memory in the CTR treated rats as reported earlier. The results suggest that Clitoria ternatea aqueous root extract enhances memory by increasing the functional growth of neurons of the amygdala.

Administration, Oral↗
PubMed1988

Morphology of surface synoviocytes in situ at normal and raised joint pressure, studied by scanning electron microscopy.

The synovial surface in rabbit knees was examined by scanning electron microscopy (SEM) to define normal surface contour, cell shape, and interstitial exposure. Comparison was made between specimens excised before immersion fixation (I), fixed in situ by vascular perfusion (V) before excision, or fixed in situ under an effusion pressure of 5-25 cmH2O (E). The deeply convoluted appearance of rabbit areolar-muscular synovium fixed after excision (I) was found to be an artefact; areolar-muscular synovium fixed in situ (V) was much smoother. The well documented cobblestone contour of immersion fixed adipose synovium was present after fixation in situ, but may be exaggerated by the SEM preparative process. At higher magnification the synoviocytes showed evidence of considerable surface activity (smooth granules, larger cauliflower-like excrescences, thin lamelliform filopodia). Cell shape was variable but many synoviocytes extended long cytoplasmic processes along the surface, producing fibroblastoid and even stellate outlines. At an intra-articular pressure of 25 cmH2O (E) the cytoplasmic processes were elongated and branched, creating a highly dendritic outline. Also, the exposure of interstitium increased markedly at the higher pressure. It is concluded that extension of lengthy cytoplasmic processes is a feature of normal healthy synoviocytes, and that an increase in interstitial area with joint pressure contributes to the increased hydraulic permeability of synovium at raised pressure.

Animals↗
PubMedDate not supplied

[The formation of definitive variants in the organization of the rudimentary portion of the thoracic duct in the prenatal period of human ontogeny].

The aim of the investigation was to find out the anatomo-topographic parallels in the development of the initial part of the thoracic duct, organs of the abdominal cavity and branches of the abdominal aorta which takes place due to taxis of the physiological umbilical hernia and secondary adhesion of the peritoneum. Specificity of these processes determines variability of branching of the abdominal artery and the formation of the duodenum, the increasing pressure to the posterior wall of the abdomen and mesentery where the presumptive lymph collectors are found. The degree of their separation by invaginations of blood vessels, the rate and spread of the development of lymph nodes are responsible for the structure and position of the initial part of the thoracic duct in human fetuses. The results obtained may be taken as a morphogenetic ground for search of the local reference points for the initial part of the thoracic duct.

Abdomen↗
PubMed2006

The coiled-coil protein shrub controls neuronal morphogenesis in Drosophila.

The diversity of neuronal cells, especially in the size and shape of their dendritic and axonal arborizations, is a striking feature of the mature nervous system. Dendritic branching is a complex process, and the underlying signaling mechanisms remain to be further defined at the mechanistic level. Here we report the identification of shrub mutations that increased dendritic branching. Single-cell clones of shrub mutant dendritic arborization (DA) sensory neurons in Drosophila larvae showed ectopic dendritic and axonal branching, indicating a cell-autonomous function for shrub in neuronal morphogenesis. shrub encodes an evolutionarily conserved coiled-coil protein homologous to the yeast protein Snf7, a key component in the ESCRT-III (endosomal sorting complex required for transport) complex that is involved in the formation of endosomal compartments known as multivesicular bodies (MVBs). We found that mouse orthologs could substitute for Shrub in mutant Drosophila embryos and that loss of Shrub function caused abnormal distribution of several early or late endosomal markers in DA sensory neurons. Our findings demonstrate that the novel coiled-coil protein Shrub functions in the endosomal pathway and plays an essential role in neuronal morphogenesis.

Animals↗
PubMedDate not supplied

Comparative toxicity of polychlorinated biphenyl and polybrominated biphenylin the rat thyroid gland: light and electron microscopic alterations after subacute dietary exposure.

The comparative toxicity of polychlorinated biphenyl (PCB) and polybrominated biphenyl (PBB) in thyroid glands was studied in male Holtzman rats. Four-week-old animals were fed at dietary levels of 0, 5, 50, and 500 ppm for 5 weeks and then sacrificed. PCB and PBB produced similar dose-dependent ultrastructural lesions in thyroid follicular cells of rats. The daily administration of 5 ppm of either PCB or PBB resulted in the accumulation of large membrane-limited colloid droplets and electron-dense lysosomal bodies within the cytoplasm of follicular cells. Microvilli were short and abnormally branched, and unique cytoplasmic processes extended from the apical surface of follicular cells into the luminal colloid. Similar but more severe ultrastructural changes were observed in thyroid glands of rats administered 50 and 500 ppm of either PCB or PBB. Many follicular cells were distended with large abnormal lysosomal bodies and colloid droplets. Mitochondria were often vacuolated with disrupted cristae. Microvilli were blunt with abnormal branching or absent from areas of the luminal surface of follicular cells. Processes of apical cytoplasm often extended into the follicular lumen in areas devoid of microvilli. Follicular cells remained responsive after the feeding of either PCB or PBB and underwent moderate compensatory hypertrophy and hyperplasia. Thyroid follicles were smaller than in controls and were lined by more columnar cells that occasionally formed papillary projections into the follicular lumens. PCB and PBB produced similar ultrastructural lesions in thyroid follicular cells which appeared to interfere with the synthesis and secretion of thyroxine.

Animals↗
PubMed2001

Interaction of linear homologous DNA duplexes via Holliday junction formation.

Interaction of linear homologous DNA duplexes by formation of Holliday junctions was revealed by electrophoresis and confirmed by electron microscopy. The phenomenon was demonstrated using a model of five purified PCR products of different size and sequence. The double-stranded structure of interacting DNA fragments was confirmed using several consecutive purifications, S1-nuclease analysis, and electron microscopy. Formation of Holliday junctions depends on DNA concentration. A thermodynamic equilibrium between duplexes and Holliday junctions was shown. We propose that homologous duplex interaction is initiated by nucleation of several dissociated terminal base pairs of two fragments. This process is followed by branch migration creating a population of Holliday junctions with the branch point at different sites. Finally, Holliday junctions are resolved via branch migration to new or previously existing duplexes. The phenomenon is a new property of DNA. This type of DNA-DNA interaction may contribute to the process of Holliday junction formation in vivo controlled by DNA conformation and DNA-protein interactions. It is of practical significance for optimization of different PCR-based methods of gene analysis, especially those involving heteroduplex formation.

Animals↗
PubMed2002

Alterations to neuronal polarity following permanent axotomy: a quantitative analysis of changes to MAP2a/b and GAP-43 distributions in axotomized motoneurons in the adult cat.

Following axotomy, morphologically unusual, distal processes (UDPs) emerge from motoneuron dendrites. These processes contain an axonal protein, growth-associated protein 43 (GAP-43) but lack immunostaining for the dendritic protein microtubule-associated protein 2a/b (MAP2a/b). Thus, it appears that neuronal polarity alters following axotomy. Our goal was to describe this change in neuronal polarity on a more detailed and quantitative level. We asked two questions: Following axotomy, where in the entire neuron does the immunoreactivity for MAP2a/b and GAP-43 change and do these changes reflect a transformation of dendrite to axon or growth from terminal dendrites? Using intracellular labeling and immunocytochemistry, changes in MAP2a/b and GAP-43 immunoreactivity were also found in processes with a morphology typical of terminal branches of intact motoneurons (called simple distal processes [SDPs]), as well as UDPs. Trajectories (the path from the soma to a single terminus) with UDPs and SDPs were longer than trajectories without these processes, and trajectories with UDPs were the longest. Trajectories without UDPs or SDPs were similar in length to trajectories from intact motoneurons. The distance from the soma to the point where MAP2a/b immunoreactivity became absent in trajectories with UDPs or SDPs was similar to the length of trajectories from intact motoneurons. Thus, following axotomy, two morphologically distinct types of axon-like processes emerge from dendrites. The formation of these processes does not involve a transformation of the original dendrite, but rather growth at the ends of dendrites.

Animals↗
PubMed1972

Acid mucopolysaccharide (glycosaminoglycan) at the epithelial-mesenchymal interface of mouse embryo salivary glands.

Acid mucopolysaccharide (glycosaminoglycan) has been demostrated at the epithelial-mesenchymal interface of mouse embryo submandibular glands by (a) specific staining for polymeric sulfate with Alcian blue 8 GX at various magnesium concentrations, (b) specific staining for polymeric uronic acid by selective oxidation of these residues to Schiff-reactive compounds, (c) electron microscope localization of ruthenium red staining, (d) radioautographic localization of glucosamine-(3)H and (35)SO(4), and (e) by susceptibility of the glucosamine radioactivity at the interface to digestion with protease-free hyaluronidase. Moreover, material labeled with glucosamine-(3)H and (35)SO(4) and with chemical characteristics identical with those of acid mucopolysaccharide were isolated from the glands. Acid mucopolysaccharide is distributed over the entire epithelial surface. The amount of acid mucopolysaccharide, as revealed by the staining procedures, is nearly equivalent at all sites. In contrast, the rate of accumulation of glucosamine-labeled mucopolysaccharide is greater at the surface of the distal ends of the growing and branching lobules. This distribution of newly synthesized acid mucopolysaccharide at the sites of incipient cleft formation suggests that surface-associated acid mucopolysaccharide is involved in the morphogenetic process. A mechanism of branching morphogenesis is proposed which accounts for the distribution of collagen fibers and total and newly synthesized acid mucopolysaccharide at the epithelial surface.

Ammonia↗
PubMed2003

Stereotyped neuropil branching of an identified stomatogastric motor neuron.

Anatomical studies of the crab stomatogastric ganglion (STG) have suggested only minimal organization within the neuropil of this structure. Here, we present evidence that, for at least one intrinsic neuron type, the ventricular dilator (VD) neuron, a highly organized and stereotyped branching structure exists within the stomatogastric neuropil. Specifically, we show the morphology of the VD neuron consists of a single primary neurite that projects from the soma into the neuropil and bifurcates into a pair of subprimary neurites, which in turn exit the neuropilar region, one entering the left and the other the right medial ventricular nerve. Nearly all secondary neurite branching of the VD neuron is from the subprimary neurites. There are approximately 22 secondary branches/neuron (range 14-28), with no significant difference between the number of secondary branches off the right vs. the left subprimary neurite, although the ratio of secondary branches between subprimaries varies (range 0.4-1.6). The fine neurites that branch from the secondary processes segregate hemispherically within the neuropil, based on the subprimary neurite of origin. Within this hemispherical organization, another level of fine neurite segregation is present, namely, the fine neurites derived from each secondary branch are restricted to discrete regions of the hemisphere with only minimal overlap with those derived from other secondary branches. Monte Carlo simulations show that this segregation differs significantly from a random distribution. The organization of branching seen in the VD neuron may play a critical role in the electrotonic and local computational organization of this neuron and sets the stage for physiological experimentation addressing these issues.

Animals↗
PubMed1995

Hominoid phylogeny estimated by model selection using goodness of fit significance tests.

Phylogeny estimation from nucleotide sequence data may be thought of as a problem of choosing between different evolutionary models that vary with the branching pattern of the phylogeny and with the stochastic process of nucleotide sequence change occurring on the branches of the phylogenetic tree. Thus, each evolutionary model consists of both a particular stochastic process and a particular phylogeny. Such models produce multinomial distributions of nucleotide character patterns. As first suggested by Cavalli-Sforza and Edwards [Evolution 21: 550-570 (1967)] the distribution of patterns expected under each model can be compared to the actual observed distribution of patterns by a goodness of fit statistic such as the loglikelihood ratio G2 or Pearson's X2 after the numerical parameters for the model have been chosen to minimize the respective statistic. For each evolutionary model, the probability P of getting a value of the goodness of fit statistic greater than the observed value is computed. A very small P value means that either a rare event has occurred or that the model is false. Employing for each of 16 models a stochastic process which has 12 parameters to describe the mode of nucleotide change on each branch of each putative phylogenetic tree, we examined all 15 unrooted dichotomously branching arrangements of orthologous noncoding sequences from the gamma hemoglobin genomic region of the five hominoids (gibbon, orangutan, gorilla, chimpanzee, and human) plus the branching arrangement with a trichotomous separation of gorilla, chimpanzee, and human. Of these 16 models, all had P values less than 0.01, except for the arrangement of human joined by chimpanzee, in turn joined by gorilla, and then orangutan and gibbon. This analysis allows convincing claims to be made about hominoid phylogenetic relationships by testing the applicability of the assumed stochastic process for nucleotide sequence evolution at the same time as testing the inferred phylogenetic branching arrangement.

Animals↗