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1.
Cytochrome b sequences of 15 species of Viverridae were used to investigate the systematic relationships of the Asiatic Viverridae and their affinities to African viverrid species. Phylogenetic analyses (maximum parsimony and neighbour-joining) supported the hypothesis of paraphyly of the subfamily Viverrinae, whereas the data suggests the monophyly of the two Viverridae subfamilies endemic to Asia. The Asiatic viverrids do not appear to have a unique origin. Results indicate that the Asiatic linsang is less closely related to the other Asiatic taxa, whereas the African civet ( Civettictis ) groups with the Asiatic civets ( Viverra , Viverricula ). The relationships between the three clades — civets, Paradoxurinae, Hemigalinae — cannot be firmly established, but they appear to be closely related together.  相似文献   

2.
Gaubert, P., Tranier, M., Delmas, A.-S., Colyn, M. & Veron, G. (2004). First molecular evidence for reassessing phylogenetic affinities between genets ( Genetta ) and the enigmatic genet-like taxa Osbornictis , Poiana and Prionodon (Carnivora, Viverridae). — Zoologica Scripta, 33 , 117–129.
The subfamily Viverrinae is a composite group of carnivores comprising the large and plantigrade terrestrial civets ( Civettictis , Viverricula and Viverra ) and the slender and generally more arboreal genets and genet-like taxa ( Genetta , Prionodon , Poiana , Osbornictis ), both having Asiatic and African representatives. The problematic phylogenetic relationships between genets and genet-like taxa are addressed for the first time from a molecular perspective through complete cytochrome b gene sequences. We used a large taxonomic sample set including some very rare and crucial species such as Osbornictis piscivora , Poiana richardsonii (museum specimen material) and Genetta johnstoni . The results from parsimony, distance and maximum likelihood analyses do not support the monophyly of the Viverrinae and contradict previous morphological hypotheses. The Asiatic linsangs ( Prionodon spp.) are excluded from the Viverrinae and represent either a basal Feliformia or Viverridae. The other genet-like taxa constitute a strongly supported monophyletic African group, in which the African linsang (represented by Poiana richardsonii ) is a sister group to the genets. The aquatic genet Osbornictis piscivora is included within the latter clade, and the genus Osbornictis should be considered a junior synonym of Genetta . African and Asiatic terrestrial civets are monophyletic, but their phylogenetic affinities with the genet-like clade are inconclusive using our data set. On the basis of our molecular results, morphological convergences and adaptations to peculiar habitats and ways of life within genets and genet-like taxa are discussed.  相似文献   

3.
The present article is the first comprehensive treatment of phytogeography of Thermopsis (Fabaceae) in the world. Thermopsis is one of the few genera within Fabaceae with the distribution pattern of the East Asia-North American disjunction. The distribution patterns of 5 recognized sections (including a new one) covering 21 species in Thermopsis are analyzed, and the results show four centres of frequency of the genus: the Eastern Asiatic Region (9 spp. / 3 sects., including 4 endemic species), the Irano-Turanian Region (7 spp./3 sects., including 3 endemic species), the Rocky Mountain Region (7 spp./2 sects., all endemic), and the Atlantic North American Region (3 spp. / 1 sect., all endemic). In the light of the fact that most species and sections, a number of phylogenetic series of the genus, and the most primitive sections and most advanced sections in Thermopsis occur in the East Asia, the Eastern Asiatic Region might be the centre of diversity of the genus. As the Irano-Turanian Region and the Rocky Mountain Region were just second to that of Eastern Asiatic Region in number of sections and species, and many polyploids appeared in these regions, they were considered as the secondary centres of distribution and speciation of the genus. The speciation looks to be frequent and complex in these regions, and many new taxa have been described from there while many new reduced or incorporated taxa have happened over there. However, recent molecular data has shown that two reduced taxa of Thermopsis are distinct in these regions. Based on the modern distribution patterns and evolutionary trends in morphological characters of the genus, and available fossil record of the genus and the historical geology, we speculate that Thermopsis had already existed on Eurasia and North America before the Late Miocene, and probably originated from an ancestral form of Sophora-like taxa with lupine alkaloids somewhere in the Laurasia in the Early Tertiary or Late Cretaceous. After the separation of the two continents, species on different continents developed distinctly under influences of different evolutionary factors. In Asia, the late Tertiary orogeny, disappearing of the Tethys and aridity and freezing caused by the Quaternary glaciation were the main forces to promote the speciation and evolutionary processes, whereas in North America it was the Quaternary glaciation and the orogeny of partial area to promote evolution of the genus. According to the evolutionary trends in Thermopsis and the distribution pattern of the primitive taxa, Sino-Japanese Subregion of Eastern Asiatic Region may be considered asthe centre of primitive forms of Thermopsis.  相似文献   

4.
Although molecular studies have helped to clarify the phylogeny of the problematic family Viverridae, a recent phylogenetic investigation based on cytochrome b (cyt b) has excluded the Asiatic linsangs (genus Prionodon) from the family. To assess the phylogenetic position of the Asiatic linsangs within the Feliformia, we analysed an exhaustive taxonomic sample set with cyt b and newly produced transthyretin intron I sequences (TR-I-I). TR-I-I alone and cyt b +TR-I-I combined (maximum-likelihood analysis) highly support the position of Asiatic linsangs as sister-group of the Felidae. The estimation of minimum divergence dates from molecular data suggests a splitting event ca. 33.3 million years (Myr) ago, which lends support to historical assertions that the Asiatic linsangs are "living fossils" that share a plesiomorphic morphotype with the Oligocene feliform Paleoprionodon. The African linsang is estimated to appear more than 20 Myr later and represents the sister-group of the genus Genetta. Our phylogenetic results illustrate numerous morphological convergences of "diagnostic" characters among Feliformia that might be problematic for the identification of fossil taxa. The morphotype reappearance from the Asiatic to the African linsangs suggests that the genome of the Feliformia conserved its potential ability of expression for a peculiar adaptive phenotype throughout evolution, in this case arboreality and hypercarnivory in tropical forest.  相似文献   

5.
The cheetah (Acinonyx jubatus) has been described as a species with low levels of genetic variation. This has been suggested to be the consequence of a demographic bottleneck 10 000–12 000 years ago (ya) and also led to the assumption that only small genetic differences exist between the described subspecies. However, analysing mitochondrial DNA and microsatellites in cheetah samples from most of the historic range of the species we found relatively deep phylogeographic breaks between some of the investigated populations, and most of the methods assessed divergence time estimates predating the postulated bottleneck. Mitochondrial DNA monophyly and overall levels of genetic differentiation support the distinctiveness of Northern‐East African cheetahs (Acinonyx jubatus soemmeringii). Moreover, combining archaeozoological and contemporary samples, we show that Asiatic cheetahs (Acinonyx jubatus venaticus) are unambiguously separated from African subspecies. Divergence time estimates from mitochondrial and nuclear data place the split between Asiatic and Southern African cheetahs (Acinonyx jubatus jubatus) at 32 000–67 000 ya using an average mammalian microsatellite mutation rate and at 4700–44 000 ya employing human microsatellite mutation rates. Cheetahs are vulnerable to extinction globally and critically endangered in their Asiatic range, where the last 70–110 individuals survive only in Iran. We demonstrate that these extant Iranian cheetahs are an autochthonous monophyletic population and the last representatives of the Asiatic subspecies A. j. venaticus. We advocate that conservation strategies should consider the uncovered independent evolutionary histories of Asiatic and African cheetahs, as well as among some African subspecies. This would facilitate the dual conservation priorities of maintaining locally adapted ecotypes and genetic diversity.  相似文献   

6.
Sideritis L. (Lamiaceae) comprises approximately 150 species of annuals and perennials distributed chiefly in the Mediterranean region. The majority of the species belong to the continental subgenus Sideritis which is divided into two perennial (Sideritis and Empedoclea) and two annual (Hesiodia and Burgsdorfia) sections. Twenty-three species are woody perennials endemic to the Macaronesian archipelagos of Madeira and the Canary Islands. In an effort to determine the continental origin of the insular group, we constructed independent phylogenies comprising sequence data from both chloroplast and nuclear markers. Sampling included 7 island taxa drawn from the Macaronesian subgenus Marrubiastrum and 25 continental taxa representing all four sections of subgenus Sideritis. Subgenus Marrubiastrum and the two continental perennial sections form well-supported monophyletic groups in both individual and combined analyses. The annual sections are not monophyletic in any analysis; further sampling of annual taxa is needed to resolve these relationships. All analyses identified Sideritis cossoniana, an annual species from Morocco, as the closest continental relative of the Macaronesian group. This contrasts with the hypothesis of earlier workers who suggested that the insular taxa were most closely related to eastern Mediterranean species of the genus. The phylogenies also demonstrate a distinct increase in woodiness among the Macaronesian species relative to their continental congeners, providing further support for the secondary nature of woodiness in island plants.  相似文献   

7.
The nuclear gene X-src is a member of the tyrosine-kinase class of proto-oncogenes whose normal product is localized within the cytoplasm of the cell. The X-src gene has been used in only a few phylogenetic studies, each focusing on systematics of killifishes (Cyprinodontiformes). The present study is an attempt to examine the phylogenetic utility of X-src for uncovering relationships of representative cichlid fishes, especially the cichlids of Middle America. The family Cichlidae is a species-rich group of tropical freshwater fish made up of more than 1000 species which show a Gondwanan pattern of distribution. Cichlid fish have been the focus of numerous studies ranging from behavioral to biogeographical to systematic in nature. Particular emphasis has focused on the cichlids of the African Great Lakes and the explosive adaptive radiation of this group. However, Neotropical cichlids have received considerably less attention than their African counterparts. Our findings regarding the utility of X-src concur with those of previous phylogenetic analyses showing the exons of X-src to be highly conserved and useful mostly for revealing deep relationships among taxa. Like previous X-src studies, we also found the intron sequences of the gene to be variable in length and difficult to align across distantly related taxa but they provided useful information for resolving relationships among more closely related taxa. The X-src phylogeny supports the monophyly of Neotropical cichlids and cichlasomines groups A (=heroines) + B (=cichlasomines). A highly resolved tree is obtained within the heroines but little support is evident for most nodes based on the low number of unambiguous substitutions. The X-src gene is likely to be quite useful for resolving deep phylogenetic relationships such as those among major groups of actinopterygian fishes.  相似文献   

8.
Drift collections of pupal exuviae from 2nd–5th order streams of the Guanacaste National Park in Northwest Costa Rica and from 3rd–6th order streams of the West African countries of Guinea, Ivory Coast, Sierra Leone and Togo have revealed high community (alpha) and regional (beta) levels of species diversity.Samples have been processed from 13 streams of the Guanacaste N. P. including two, Quebrada Las Yeguitas (2 stations) and Rio Tempisquito, for which year-long series were available. A total of 266 species level taxa have been recognized from these streams and are distributed over the higher taxa as follows: Chironomini-73, Pseudochironomini-4, Tanytarsini-55, Orthocladiinae-92, Macropelopiini-5 and Pentaneurini-37. The two sites on the Q. Las Yeguitas have a combined total of 216 species, and together with R. Tempisquito a total of 238 species. The single richest sample (Q. Las Yeguitas, Orosi station, 1990-Jan.-9) contained 102 species.Samples have been processed from 31 West African Streams which, for the most part, are represented by single samples. A total of 299 species level taxa have been recognized from these streams which are distributed over the higher taxa as follows: Chrinomini-139, Tanytarsini-62, Orthocladiinae-56, Coelotanypodini-2, Macropelopiini-3 and Pentaneurini-37. The single largest collection, containing 175 species, was taken from the Upper Dion River, a 6th order stream in the Upper Niger basin of the Guinean highlands.The compositions of the two regional faunas show similarities in two general features: they are both taxonomically narrow (few subfamilies and tribes) and taxonomically deep (many closely related genera, often with a relatively large number of closely related species). The high alpha diversity values require an ecological explanation, most probably along the axes of resources (time, space and food). The high regional diversities require an historical explanation. It is proposed that great climatic variation during the Pleistocene coupled with great geographic alteration of the connection between North and South America may be responsible for both the taxonomic narrowness and depth seen in the chironomid faunas of West Africa and Costa Rica.  相似文献   

9.
The genus Festuca comprises approximately 450 species and is widely distributed around the world. The Iberian Penninsula, with more than 100 taxa colonizing very diverse habitats, is one of its main centers of diversification. This study was conducted to assess molecular genetic variation and genetic relatedness among 91 populations of 31 taxa of Iberian fescues, based on several molecular markers (random amplified polymorphic DNA, amplified fragment length polymorphisms, and trnL sequences). The analyses showed the paraphyletic origin of the broad-leaved (subgenus Festuca, sections Scariosae and Subbulbosae, and subgenus Schedonorus) and the fine-leaved fescues (subgenus Festuca, sections Aulaxyper, Eskia, and Festuca). Schedonorus showed a weak relationship with Lolium rigidum and appeared to be the most recent of the broad-leaved clade. Section Eskia was the most ancient and Festuca the most recent of the fine-leaved clade. Festuca and Aulaxyper were the most related sections, in concordance with their taxonomic affinities. All taxa grouped into their sections, except F. ampla and F. capillifolia (section Festuca), which appeared to be more closely related to Aulaxyper and to a new independent section, respectively. Most populations clustered at the species level, but some subspecies and varieties mixed their populations. This study demonstrated the value in combining different molecular markers to uncover hidden genetic relationships between populations of Festuca.  相似文献   

10.
嵩草属地理分布的研究   总被引:8,自引:0,他引:8  
嵩草属Kobresia Willd.隶属于莎草科,全世界有64种5变种,中国有49种4变种,属下分为4个组。该属主要分布于北半球温带至寒带,亚洲种类最多,主要集中分布于喜马拉雅山地区和横断山地区。上述两地共有总数的90%以上的种类。因此,喜马拉雅-横断山地区为嵩草属的分布中心。与嵩草属最近缘的属Schoenoxiphium只分布在马达加斯加和非洲东南部山地。两个属可能有共同的祖先,发生于冈瓦纳古陆。随着印度板块与非洲大陆分离并向北方漂移,嵩草属的祖先被带到欧亚大陆,在两个板块相遇处——喜马拉雅-横断山地区产生了现在的嵩草属。其后,喜马拉雅山脉进一步抬升,气候与环境发生巨变,嵩草属也进一步分化形成现在的规模。印度板块在早第三纪与欧亚大陆相连接,嵩草属可能就是此时起源于喜马拉雅山地区,并开始分化,且沿北半球的山系向北扩散到欧洲和西伯利亚,又从欧洲到格陵兰再到加拿大东部,从西伯利亚通过白令海峡到阿拉斯加并沿落基山脉南下达到美国的科罗拉多,形成了嵩草属现今的分布格局。  相似文献   

11.
G. B. CORBET 《Mammal Review》1988,18(3):117-172
All species and higher taxa of Recent Erinaceidae are diagnosed, the character-states most useful in classification are tabulated and the most probable phylogenies presented. Four African species are included in the genus Atelerix. The desert-adapted Paraechinus is believed to be more closely related to Atelerix than to the convergent Hemiechinus. The ranges of all species are mapped, with emphasis upon areas of parapatry and sympatry. Marginal localities are listed if they are not derived from previously published maps. All nominal fossil species that have been allocated to Recent genera are listed. Ecological data relevant to the interpretations of species boundaries, e.g. relating to diet and habitat, are summarized, and the factors likely to determine the species boundaries are reviewed.  相似文献   

12.
Chloroplast DNA (cpDNA) restriction site variation (RFLP), has been analysed in the genus Cochlearia L. sections Cochlearia O.E. Schulz and Glaucocochlearia O.E. Schulz. Members of section Glaucocochlearia are clearly separated from those of section Cochlearia by 28 site mutations, thus supporting taxonomic arrangements into the two sections mentioned. RAPD studies provide further strong evidence for closer relationships among tax a within each section than between sections. CpDNA sequence divergence values in section Cochlearia are extremely low. Although 91 accessions representing 11 species have been analysed by 25 restriction enzymes, only four restriction site mutations were detected characterising six different cp genome types. Low levels of chloroplast DNA divergence would suggest that taxa of section Cochlearia are closely related and most likely have diversified recently. Polyploid Cochlearia offcinalis (2n=24), C. anglica (2n=48) and C. danica (2n=42) displayed infraspecific variation for cp genomes, which could be partly explained by multiple origin and by reticulate evolution. RAPD analyses (22 primers, 140 informative characters, ten taxa from 17 accessions) do not only strongly support these arguments but also helped to clarify speciation processes and biogeographic aspects in more detail. It is argued that South West Europe was the primary center of origin of the polyploids, second centers may be the British Isles, Iceland and locally restricted parts of Middle Europe.  相似文献   

13.
The late Miocene North African mammalianassemblage is considered here from three viewpoints: survivals, extinctions, and immigrations. The Eurasiatic affinities of the large mammals slightly prevail over the Ethiopian affinities. Amongst the North African large mammals, 4 to 8 taxa are Eurasiatic immigrants, while 4 to 6 are of Subsaharian origin. Contrarily, the micromammalian fauna is highly endemic, with only one species, a murid (Paraethomys miocaenicus), considered here as being related to an Asiatic form (Karnimata darwini). Our study of Eurasian and African Miocene faunas reveals that during the late Astaracian-early Turolian interval, the Saharo-Arabic belt permitted very little latitudinal faunal exchanges. However, during the middle and late Turolian such faunal exchanges became frequent. The micromammal record unequivocally indicates that a brief period of faunal exchange occurred between Africa and western Europe at the end of the Miocene, corresponding with the Messinian Salinity Crisis. The increased intercontinental faunal exchange between Africa and Eurasia during the late Miocene coincides with, and counterbalances the extinction of more than 10 taxa at the Mio/Pliocene boundary.  相似文献   

14.
The molecular phylogeny of the genus Allium which includes eighteen species selected from nine sections was investigated through PCR-RFLP analysis of two chloroplast DNA fragments, including trak gene (approximately 2 520 bp) and rpL16 gene (approximately 1 230 bp). Digestion of these two fragments by 26 restriction endonucleases yielded 303 polymorphic recognition sites, of which 163 were informative sites. The restriction site data matrix were analyzed following the parsimonious Wagner and parsimonious Dollo principle of PAUP ( version 3.1.1 ). Topologically, the most parsimonious Wagner tree constructed by branch-and-bound and heuristic search was similar to the most parsimonious Dollo tree. All the taxa of Allium form a monophyletic group, and five sections based on morphological characters were supported strongly by this result. Sect. Augninum is closely related to Sect. Bromatorrhiza, Sect. Molium is closely related to Sect. Caloscordum. Their reliability was farther confirmed by the bootstrap test very well. In morphology, A. pallasii is closely related to A. caeruleum and belongs to Sect. Haplostemen, A. cepa is closely related to A. galanthum and belongs to Sect. Cepa. But evidence from cladistics of parsimonious tree based on 163 informative sites of PCR-RFLPs showed that they are neither confined to a monophyletic group nor to a natural taxon.  相似文献   

15.
毛茛科金莲花亚科植物的地理分布   总被引:11,自引:1,他引:10  
本文对毛茛科金莲花亚科各属的地理分布作了分析,该亚科植物除了少数属的一些种分布到南半球的温带地区,一些种分布或延伸到亚热带山地、非洲东部和北部的干旱、半干旱的地区外,绝大部分的属、种均分布于泛北极区域。根据其17个属的地理分布式样,把它们划分为8个分布区类型:(1)北温带分布类型4属;(2)北温带和非洲分布类型1属;(3)北半球温带和南半球间断分布类型1属;(4)欧洲和东亚间断分布类型1属;(5)西亚分布类型1属;(6)地中海分布类型3属;(7)欧亚和温带亚洲分布类型1属;(8)东亚分布类型5属。本文以形态特征为主,结合花粉和染色体的性状分析,认为东亚特有的鸡爪草属、Megaleranthis和铁破锣属可能分别是联系驴蹄草属和金莲花属,鸡爪草属和金莲花属以及金莲花族和升麻族的中间类型。另外,文中详细地统计了该亚科的不同等级分类群及特有种在各个植物区的分布,并从系统发育的观点讨论了各个植物区所具有的原始类群和进化类群,提出了如下论点,即东亚植物区(特别是中国西南部)不但是金莲花亚科植物分布的多度和多样性中心以及特有类群的分布中心,而且还是原始类群的保存中心,伊朗-土兰区及地中海周围是第二分布中心。  相似文献   

16.
The evolution of perissodactyls (rhinoceroses, tapirs, and horses) has been well studied primarily because of their extensive fossil record. Nevertheless, controversy persists regarding relationships of some of the extant taxa, reflecting inconsistencies between molecular and morphological studies. Here we examine the phylogenetic relationships of 16 living perissodactyl species by concatenating two mitochondrial and nine nuclear genes, and we estimate their divergence times using a relaxed Bayesian molecular clock approach. Our analyses recovered the monophyly of the suborders Ceratomorpha and Hippomorpha, and the families Rhinoceratidae, Tapiridae, and Equidae. We supported the early divergence of the Indian rhinoceros in the late Oligocene (26 Mya) relative to the Sumatran and African rhinoceroses, and the split of caballine (domestic horse and Przewalski's wild horse) and noncaballine equids (zebras and African and Asiatic asses) in the Pliocene (4 Mya). An important implication of this study is that Equus asinus, the African wild ass was found to be the sister taxon of Asiatic asses and zebras, diverging from the common ancestor with caballine horses 2 Mya. Rates of chromosome rearrangements were also evaluated in perissodactyls, placing a notably high rate of variation amongst equids, particularly within the zebra clade. The robust phylogenetic results presented here are relevant in terms of understanding the evolutionary history of this highly threatened group of mammals. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 1289–1303.  相似文献   

17.
The Red Sea has had a profound biogeographic effect on organisms with Afro-Asian distributions, resulting in complex patterns of admixture on the Arabian Peninsula. We investigate the phylogenetic affinities of a monitor lizard (Varanus yemenensis) restricted to the southwestern Arabian Peninsula by sequencing all African monitor species and several Asian monitor species for the mitochondrial gene ND2 and the nuclear marker RAG-1. We find evidence that V. yemenensis is of African origin, being most closely related to the white-throat monitor, V. albigularis, an African species complex distributed from the Horn of Africa to southern Africa. Using divergence-dating analyses, we investigate several biogeographic hypotheses to infer the likely mechanism of colonization of the Arabian Peninsula by this species. Our results reveal that both dispersal across a southern land bridge and overwater dispersal are potential explanations. The patterns observed in V. yemenensis are contrasted with other taxa having similar Afro-Arabian disjunct distributions to better understand the complex biogeographic history of this region.  相似文献   

18.
BACKGROUND AND AIMS: The genus Bupleurum has long been recognized as a natural group, but its infrageneric classification is controversial and has not yet been studied in the light of sequence data. METHODS: Phylogenetic relationships among 32 species (35 taxa) of the genus Bupleurum were investigated by comparative sequencing of the ITS region of the 18-26S nuclear ribosomal DNA repeat. Exemplar taxa from all currently accepted sections and subsections of the genus were included, along with outgroups from four other early branching Apioideae genera (Anginon, Heteromorpha, Physospermum and Pleurospermum). RESULTS: Phylogenies generated by maximum parsimony, maximum likelihood, and neighbour-joining methods show similar topologies, demonstrating monophyly of Bupleurum and the division of the genus into two major clades. This division is also supported by analysis of the 5.8S coding sequence alone. The first branching clade is formed by all the species of the genus with pinnate-reticulate veined leaves and B. rigidum with a unique type of leaf venation. The other major clade includes the remaining species studied, all of which have more or less parallel-veined leaves. CONCLUSIONS: These phylogenetic results do not agree with any previous classifications of the genus. Molecular data also suggest that the endemic Macaronesian species B. salicifolium is a neoendemic, as the sequence divergence between the populations in Madeira and Canary Islands, and closer mainland relatives in north-west Africa is small. All endemic north-west African taxa are included in a single unresolved but well-supported clade, and the low nucleotide variation of ITS suggests a recent radiation within this group. The only southern hemisphere species, B. mundii (southern Africa), is shown to be a neoendemic, apparently closely related to B. falcatum, a Eurasian species.  相似文献   

19.
Tetsuo Koyama 《Brittonia》1984,36(2):184-205
Heterosmilax, a small southeastern Asiatic genus in the Smilacaceae, comprises 11 species in two sections, includingH. micrandra, which is described as new from Hainan, China. These taxa are taxonomically discussed, described, illustrated, and a key is provided to differentiate them.  相似文献   

20.
Genomic comparison between apes and humans have made important contributions to our understanding of human evolution. The modern period of karyological comparisons between humans and other primates began about forty years ago and has been marked by a series of technical revolutions. In the 1960s pioneering genetic and chromosomal comparisons of human and great apes suggested, as had Darwin a century before, that our closest relative were the African apes. Early immunological analyses placed human/apes divergence at about five million year ago. Acceptance of man’s late divergence from the African apes was delayed by the scarcity of paleontological evidence coupled with a fallacious Asiatic origin hypothesis of the hominoids. Chromosome banding techniques in the seventies and high resolution methods in the eighties allowed a detailed comparison of the chromosomes between closely related primates and reinforced the hypothesis of an African origin for humans. It was clearly shown that humans were more closely related to African apes than to the orang-utan. The last decade has seen a vigorous integration of molecular and cytogenetic. This powerful combination promises to be quite fruitful because chromosomes can be compared directly at the DNA level. Fluorescentin situ hybridisation (FISH), chromosome painting, is a colourful technique for establishing chromosomal homology between species. Results obtained by FISH over the last ten years have resolved the cytogenetic problem of the homology between humans, apes, hylobates and Old World monkeys and defined the chromosomal syntenies and major translocations involved in the genome evolution of higher primates.  相似文献   

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