Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Mandrillus”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

Ontogeny and homoplasy in the papionin monkey face.

Recent molecular research has provided a consistent estimate of phylogeny for the living papionin monkeys (Cercocebus, Lophocebus, Macaca, Mandrillus, Papio, and Theropithecus). This phylogeny differs from morphological phylogenies regarding the relationships of the mangabeys (Cercocebus and Lophocebus) and baboons (Mandrillus, Papio, and Theropithecus). Under the likely assumption that the molecular estimate is correct, the incongruence between the molecular and morphological data sets indicates that the latter include numerous homoplasies. Knowledge of how these homoplasies emerge through development is important for understanding the morphological evolution of the living papionins, and also for reconstructing the phylogenetic relationships and adaptations of their fossil relatives. Accordingly, we have used geometric morphometric techniques and the molecular phylogeny to investigate the ontogeny of a key area of morphological homoplasy in papionins, the face. Two analyses were carried out. The first compared allometric vectors of Cercocebus, Lophocebus, Macaca, Mandrillus, and Papioto determine which of the facial resemblances among the genera are homoplasic and which are plesiomorphic. The second analysis focused on early post-natal facial form in order to establish whether the facial homoplasies exhibited by the adult papionins are to some degree present early in the post-natal period or whether they develop only later in ontogeny. The results of our analyses go some way to resolving the debate over which papionin genera display homoplasic facial similarities. They strongly suggest that the homoplasic facial similarities are exhibited by Mandrillus and Papio and not by Cercocebus and Lophocebus, which share the putative primitive state with Macaca. Our results also indicate that Mandrillus and Papio achieve their homoplasic similarities in facial form not through simple extension of the ancestral allometric trajectory but through a combination of an extension of allometry into larger size ranges and a change in direction of allometry away from the ancestral trajectory. Thus, the face of Mandrillus is not simply a hypermorphic version of the face of its sister taxon, Cercocebus, and the face of Papio is not merely a scaled-up version of the face of its sister taxon, Lophocebus. Lastly, our results show that facial homoplasy is not restricted to adult papionins; it is also manifest in infant and juvenile papionins. This suggests that the homoplasic facial similarities between Mandrillus and Papio are unlikely to be a result of sexual selection.

Animals↗

Skeletal and dental morphology of African papionins: unmasking a cryptic clade.

One of the more perplexing problems in primate systematics concerns the phyletic relationships of the large African monkeys--Mandrillus (including drills), Papio, Lophocebus and Cercocebus. For over twenty years, there has been molecular evidence that mangabeys are an unnatural group and that the terrestrial forms--Cercocebus--are the sister taxon of Mandrillus, while the arboreal forms--Lophocebus--are more closely allied with Papio. Nevertheless, most systematists have been reluctant to accept this scheme due to the lack of morphological evidence. In this paper, we undertake a detailed analysis of the scapula, humerus, radius, ulna, pelvis, femur and dentition of papionin primates. We identify a host of features shared by Cercocebus and Mandrillus to the exclusion of Lophocebus and Papio. The polarity of characters is established by examining an outgroup comprised of several species of Macaca. The features shared by Cercocebus and Mandrillus are functionally related to specific feeding and locomotor behaviors that include aggressive manual foraging, the processing of hard-object foods and the climbing of vertical trunks. We hypothesize that the ability to subsist on hard seeds and nuts gleaned from the forest floor is a key adaptation for the Cercocebus-Mandrillus clade.

Anatomy, Comparative↗

Simian homologues of human gamma-2 and betaherpesviruses in mandrill and drill monkeys.

Recent serological and molecular surveys of different primate species allowed the characterization of several Kaposi's sarcoma-associated herpesvirus (KSHV) homologues in macaques, African green monkeys, chimpanzees, and gorillas. Identification of these new primate rhadinoviruses revealed the existence of two distinct genogroups, called RV1 and RV2. Using a degenerate consensus primer PCR method for the herpesvirus DNA polymerase gene, the presence of KSHV homologues has been investigated in two semi-free-ranging colonies of eight drill (Mandrillus leucophaeus), five mandrill (Mandrillus sphinx), and two hybrid (Mandrillus leucophaeus-Mandrillus sphinx) monkeys, living in Cameroon and Gabon, Central Africa. This search revealed the existence of not only two distinct KSHV homologues, each one belonging to one of the two rhadinovirus genogroups, but also of two new betaherpesvirus sequences, one being close to cytomegaloviruses and the other being related to human herpesviruses 6 and 7 (HHV-6 and -7). The latter viruses are the first simian HHV-6 and -7 homologues identified to date. These data show that mandrill and drill monkeys are the hosts of at least four novel distinct herpesviruses. Moreover, mandrills, like macaques and African green monkeys, harbor also two distinct gamma-2 herpesviruses, thus strongly suggesting that a second gamma-2 herpesvirus, belonging to the RV2 genogroup, may exist in humans.

Animals↗

Structural colouration of mammalian skin: convergent evolution of coherently scattering dermal collagen arrays.

For more than a century, the blue structural colours of mammalian skin have been hypothesized to be produced by incoherent, Rayleigh or Tyndall scattering. We investigated the colour, anatomy, nanostructure and biophysics of structurally coloured skin from two species of primates - mandrill (Mandrillus sphinx) and vervet monkey (Cercopithecus aethiops) - and two species of marsupials - mouse opossum (Marmosa mexicana) and wooly opossum (Caluromys derbianus). We used two-dimensional (2-D) Fourier analysis of transmission electron micrographs (TEMs) of the collagen arrays in the primate tissues to test whether these structural colours are produced by incoherent or coherent scattering (i.e. constructive interference). The structural colours in Mandrillus rump and facial skin and Cercopithecus scrotum are produced by coherent scattering by quasi-ordered arrays of parallel dermal collagen fibres. The 2-D Fourier power spectra of the collagen arrays from Mandrillus and Cercopithecus reveal ring-shaped distributions of Fourier power at intermediate spatial frequencies, demonstrating a substantial nanostructure of the appropriate spatial frequency to produce the observed blue hues by coherent scattering alone. The Fourier power spectra and the observed reflectance spectra falsify assumptions and predictions of the incoherent, Rayleigh scattering hypothesis. Samples of blue Marmosa and Caluromys scrotum conform generally to the anatomy seen in Mandrillus and Cercopithecus but were not sufficiently well preserved to conduct numerical analyses. Colour-producing collagen arrays in mammals have evolved multiple times independently within the two clades of mammals known to have trichromatic colour vision. Mammalian colour-producing collagen arrays are anatomically and mechanistically identical to structures that have evolved convergently in the dermis of many lineages of birds, the tapetum of some mammals and the cornea of some fishes. These collagen arrays constitute quasi-ordered 2-D photonic crystals.

Animals↗

Molecular phylogeny of Old World monkeys (Cercopithecidae) as inferred from gamma-globin DNA sequences.

DNA sequence data of the nuclear-encoded gamma1-gamma2-globin duplication region were used to examine the phylogenetic relationships of 16 cercopithecid (Old World monkey) species representing 12 extant genera. Morphology- and molecular-based hypotheses of Old World monkey branching patterns are generally congruent, except for generic relationships within the subtribe Papionina. The cercopithecids divide into colobines (leaf-eating monkeys) and cercopithecines (cheek-pouched monkeys). The colobines examined by the DNA data divide into an Asian clade (Nasalis, proboscis monkeys; Trachypithecus, langurs) and an African clade (Colobus, colobus monkeys). The cercopithecines divide into tribes Cercopithecini (Erythrocebus, patas monkey; Chlorocebus, green monkeys; Cercopithecus, guenons) and Papionini. Papionins divide into subtribes Macacina (Macaca, macaques) and Papionina (Papio, hamadryas baboons; Mandrillus, drills and mandrills; Theropithecus, gelada baboons; Lophocebus, arboreal mangabeys; Cercocebus, terrestrial mangabeys). In a morphologically based classification, Mandrillus is a subgenus of Papio, whereas Lophocebus is a subgenus of Cercocebus. In contrast, the molecular evidence treats Mandrillus as a subgenus of Cercocebus, and treats both Theropithecus and Lophocebus as subgenera of Papio. Local molecular clock divergence time estimates were used as a yardstick in a "rank equals age" system to propose a reduction in taxonomic rank for most clades within Cercopithecidae.

Animals↗

Skeletal and dental morphology supports diphyletic origin of baboons and mandrills.

Numerous biomolecular studies from the past 20 years have indicated that the large African monkeys Papio, Theropithecus, and Mandrillus have a diphyletic relationship with different species groups of mangabeys. According to the results of these studies, mandrills and drills (Mandrillus) are most closely related to the torquatus-galeritus group of mangabeys placed in the genus Cercocebus, whereas baboons (Papio) and geladas (Theropithecus) are most closely related to the albigena-aterrimus mangabeys, now commonly placed in the genus Lophocebus. However, there has been very little morphological evidence linking mandrills on the one hand and baboons and geladas on the other with different groups of mangabeys. In a study of mangabey locomotion and skeletal anatomy, we have identified features of the postcranial skeleton and the dentition that support the molecular phylogeny and clearly link mandrills with Cercocebus and Papio with Lophocebus. Moreover, the features linking Cercocebus and Mandrillus accord with ecological studies of these species indicating that these two genera are a cryptic clade characterized by unique adaptations for gleaning insects, hard nuts, and seeds from the forest floor.

Animals↗

Natural simian foamy virus infection in wild-caught gorillas, mandrills and drills from Cameroon and Gabon.

A survey for the presence of simian foamy retroviruses (SFVs) was performed in 44 wild-caught apes and monkeys, including 27 gorillas, 11 mandrills and six drills, originating from south Cameroon or Gabon. Combined serological and/or nested-PCR assays indicated SFV infection among five Gorilla gorilla gorilla, seven Mandrillus sphinx and two Mandrillus leucophaeus. Sequences of a 425 bp fragment of the integrase gene were obtained for 11 animals. Phylogenetic studies indicated that strains from gorillas, mandrills and drills each formed a highly supported phylogenetic clade with, moreover, the existence of two different gorilla SFVs. This study demonstrates for the first time that these animals are naturally infected with specific SFVs. In the context of simian-to-human interspecies transmission, the results confirm that such viruses can also infect humans, as the SFVs identified in wild-caught animals were the same as those recently reported as infecting hunters living in the same geographical areas.

Animals↗

Evolutionary breakpoints are co-localized with fragile sites and intrachromosomal telomeric sequences in primates.

The concentration of evolutionary breakpoints in primate karyotypes in some particular regions or chromosome bands suggests that these chromosome regions are more prone to breakage. This is the first extensive comparative study which investigates a possible relationship of two genetic markers (intrachromosomal telomeric sequences [TTAGGG]n, [ITSs] and fragile sites [FSs]), which are implicated in the evolutionary process as well as in chromosome rearrangements. For this purpose, we have analyzed: (a) the cytogenetic expression of aphidicolin-induced FSs in Cebus apella and Cebus nigrivittatus (F. Cebidae, Platyrrhini) and Mandrillus sphinx (F. Cercopithecidae, Catarrhini), and (b) the intrachromosomal position of telomeric-like sequences by FISH with a synthetic (TTAGGG)n probe in C. apella chromosomes. The multinomial FSM statistical model allowed us to determinate 53 FSs in C. apella, 16 FSs in C. nigrivittatus and 50 FSs in M. sphinx. As expected, all telomeres hybridized with the probe, and 55 intrachromosomal loci were also detected in the Cebus apella karyotype. The chi(2) test indicates that the coincidence of the location of Cebus and Mandrillus FSs with the location of human FSs is significant (P < 0.005). Based on a comparative cytogenetic study among different primate species we have identified (or described) the chromosome bands in the karyotypes of Papionini and Cebus species implicated in evolutionary reorganizations. More than 80% of these evolutionary breakpoints are located in chromosome bands that express FSs and/or contain ITSs.

Animals↗

SIVdrl detection in captive mandrills: are mandrills infected with a third strain of simian immunodeficiency virus?

A pol-fragment of simian immunodeficiency virus (SIV) that is highly related to SIVdrl-pol from drill monkeys (Mandrillus leucophaeus) was detected in two mandrills (Mandrillus sphinx) from Amsterdam Zoo. These captivity-born mandrills had never been in contact with drill monkeys, and were unlikely to be hybrids. Their mitochondrial haplotype suggested that they descended from founder animals in Cameroon or northern Gabon, close to the habitat of the drill. SIVdrl has once before been found in a wild-caught mandrill from the same region, indicating that mandrills are naturally infected with a SIVdrl-like virus. This suggests that mandrills are the first primate species to be infected with three strains of SIV: SIVmnd1, SIVmnd2, and SIVdrl.

Animals↗

Generic level relationships of the Papionini (Cercopithecoidea).

Phylogenetic hypotheses for the Old World monkey tribe Papionini based on molecular data are incongruent with those inferred from previous morphological analyses. Morphologists have often inferred a close relationship between Mandrillus and Papio based on their overall similarity. Theropithecus has been variously proposed to be either quite distantly related to these two genera, their sister taxon, or anywhere in between. Molecular and chromosomal analyses on the other hand unambiguously group Theropithecus and Papio together to the exclusion of Mandrillus. Additionally, molecular and chromosomal analyses reveal that mangabeys (Cerocebus) are paraphyletic. Morphologists have acknowledged this possibility resurrecting the genus name Lophocebus for one group of mangabeys. A review and reanalysis of the morphological characters put forth by various researchers find little to contradict the consensus phylogeny derived from analysis of chromosomal banding, nuclear RNA restriction mapping, alpha and beta hemoglobin sequences, albumin and transferrin microcomplement fixation, DNA-DNA hybridization, repetitive DNA patterns, immunodiffusion, hemoglobin and adenylate kinase isozymes, and mitochondrial cytochrome oxidase subunit II DNA sequences.

Animals↗

Molecular systematics of the old world monkey tribe papionini: analysis of the total available genetic sequences.

The phylogenetic relationships among the genera of the tribe Papionini are inferred using a taxonomic congruence approach in which gene trees derived for eight unlinked genetic sequence datasets are compared. Population genetics theory predicts that species relationships will be revealed with greater probability when the topology of gene trees from many unlinked loci are found to be congruent. The theory underlying this approach is described. Monophyly of the mangabeys is not supported by any of the gene trees; instead, they are polyphyletic with Cercocebus found to be the sister taxon to Mandrillus in five gene trees (with no conflicting trees), and Lophocebus found to be closely related to Papio and/or Theropithecus in all trees. Theropithecus and Papio are not strongly supported as sister taxa (present in one or two trees only);Lophocebus and Papio are supported as sister taxa in the majority of trees. A close relationship between Mandrillus and Papio is not supported in any of the trees.The relationships among Papio, Lophocebus, and Theropithecus cannot be resolved by congruence, probably due to the short time interval estimated between their divergences. The mtDNA COII sequences are used to estimate divergence dates within the papionins. The internode between the divergences of these species is estimated to be between 290 ka and 370 ka. Lastly, the evolution of morphological features such as long faces, suborbital facial fossae, and terrestrial skeletal adaptations is discussed.

Animals↗

Patterns of cranial shape variation in the Papionini (Primates: Cercopithecinae).

Traditional classifications of the Old World monkey tribe Papionini (Primates: Cercopithecinae) recognized the mangabey genera Cercocebus and Lophocebus as sister taxa. However, molecular studies have consistently found the mangabeys to be diphyletic, with Cercocebus and Mandrillus forming a clade to the exclusion of all other papionins. Recent studies have identified cranial and postcranial features which distinguish the Cercocebus-Mandrillus clade, however the detailed similarities in cranial shape between the mangabey genera are more difficult to reconcile with the molecular evidence. Given the large size differential between members of the papionin molecular clades, it has frequently been suggested that allometric effects account for homoplasy in papionin cranial form. A combination of geometric morphometric, bivariate, and multivariate methods was used to evaluate the hypothesis that allometric scaling contributes to craniofacial similarities between like-sized papionin taxa. Patterns of allometric and size-independent cranial shape variation were subsequently described and related to known papionin phylogenetic relationships and patterns of development. Results confirm that allometric scaling of craniofacial shape characterized by positive facial allometry and negative neurocranial allometry is present across adult papionins. Pairwise comparisons of regression lines among genera revealed considerable homogeneity of scaling within the Papionini, however statistically significant differences in regression lines also were noted. In particular, Cercocebus and Lophocebus exhibit a shared slope and significant vertical displacement of their allometric lines relative to other papionins. These findings give no support to narrowly construed hypotheses of uniquely shared patterns of allometric scaling, either between sister taxa or across all papionins. However, more general allometric trends do appear to account for a substantial proportion of papionin cranial shape variation, most notably in those features which have influenced traditional morphological phylogenies. Examination of size-uncorrelated shape variation gives no clear support to molecular phylogenies, but underscores the absence of morphometric similarities between the mangabey genera when size effects are controlled. Patterns of allometric and size-uncorrelated shape variation indicate conservatism of cranial form in non- Theropithecus papionins, and suggest that Papio represents the primitive morphometric pattern for the African papionins. Lophocebus exhibits a divergent morphometric pattern, clearly distinguishable from other papionins, most notably Cercocebus. These results clarify patterns of cranial shape variation among the extant Papionini and lay the groundwork for studies of related fossil taxa.

Animals↗

Ontogeny and phylogeny in papionin primates.

This study investigates the developmental bases of size and shape variation in papionin primates (Macaca, Cercocebus, Mandrillus, Lophocebus, and Papio). The analysis tests hypotheses predicting that heterochronic changes in ontogeny, particularly in the degree of overall size growth, can account for cranial diversity and "allometric scaling" in this clade. Large developmental samples of extant papionin crania are examined to test heterochronic hypotheses using bivariate allometric methods. Analyses indicate that the crania of larger papionins (Mandrillus and Papio) are generally peramorphic, surpassing size and shape ranges of smaller, and probably less-derived, macaques and mangabeys. At least two heterochronic processes, including acceleration and hypermorphosis, can account for this pattern. Ontogenetic changes include decoupling of growth and development among cranial regions, along with simple shifts in size. Allometric scaling has complex developmental bases. Size change itself is not sufficient to explain all developmental differences among papionins, but these changes are extremely important in comparisons within cranial regions such as the face. Results imply that Papio exhibits strongly derived patterns of brain growth that impact postnatal patterns of size and shape transformation. Consideration of these results in the context of recent socioecological analyses suggests that derived patterns of cranial growth in Papio may be a response to selection during the early periods of ontogeny, resulting in a distinctive life history pattern.

Animals↗

Mitochondrial DNA phylogeny of the Old-World monkey tribe Papionini.

The evolution of the Old World monkey tribe Papionini, composed of macaques, baboons, mandrills, drills, and mangabeys, was examined using mitochondrial DNA (mtDNA) sequence data on the cytochrome oxidase subunit II gene. When analyzed cladistically, these data support a baboon clade of savannah (Papio) plus gelada (Theropithecus) baboons, as well as a clade containing drill (Mandrillus) plus mangabey (Cerocebus) genera. This result stands in opposition to most morphological phylogenies, which break up the baboon clade by placing Papio and Mandrillus as sister taxa and Theropithecus as a more distantly related lineage. Analyses of COII gene sequences also suggest that the papionin ancestral stock divided into two lineages, one leading to macaques and the other to the purely African genera. From a molecular evolutionary perspective, the papionin COII gene sequences reveal a pattern of amino acid replacements concentrated in the regions spanning the mitochondrial membrane.

Amino Acid Sequence↗

Molecular epidemiology of simian T-lymphotropic virus (STLV) in wild-caught monkeys and apes from Cameroon: a new STLV-1, related to human T-lymphotropic virus subtype F, in a Cercocebus agilis.

A serological survey for human T-lymphotropic virus (HTLV)/simian T-lymphotropic virus (STLV) antibodies was performed in 102 wild-caught monkeys and apes from 15 (sub)species originating from Cameroon. Two animals (a Mandrillus sphinx and a Cercocebus agilis) exhibited a complete HTLV-1 seroreactivity pattern while two others lacked either the p24 (a Mandrillus sphinx) or the MTA-1/gp46 bands (a Pan troglodytes). Sequence comparison and phylogenetic analyses, using a 522 bp env gene fragment and the complete LTR, indicated that the two mandrill STLV strains belonged to the HTLV/STLV subtype D clade while the chimpanzee strain clustered in the HTLV/STLV subtype B clade. The Cercocebus agilis STLV strain, the first one found in this species, was closely related to the two HTLV/STLV subtype F strains. Such data indicate that the African biodiversity of STLV-1 in the wild is far from being known and reinforces the hypothesis of interspecies transmission of STLV-1 from monkeys and apes to humans leading to the present day distribution of HTLV-1 in African inhabitants.

Animals↗

Conservation of aphidicolin-induced fragile sites in Papionini (Primates) species and humans.

Fragile sites are considered structural features of mammalian chromosomes and a commonly repeated hypothesis is that they are evolutionarily conserved. We tested this hypothesis by establishing the subchromosomal homology of regions harbouring fragile sites in the chromosomes of humans, Macaca fascicularis (MFA) and Mandrillus sphinx (MSP). We delineated the interspecific homology of chromosome bands expressing aphidicolin-induced fragile sites of homologues to human chromosomes 1, 3, 5, 7, 18 and X by the comparative FISH of human BAC and YAC clones. Notably, two YAC clones known to span human chromosome regions containing fragile sites were shown to also span fragile sites in macaques and mandrills. The present comparative BAC/YAC mapping data represent, up to now, the most precise evidence of fragile site conservation during primate evolution.

Animals↗