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1.
Palha Tde J Ribeiro-Rodrigues EM Ribeiro-dos-Santos A Guerreiro JF de Moura LS Santos S 《American journal of physical anthropology》2011,144(3):471-478
Some genetic markers on both the Y chromosome and mtDNA are highly polymorphic and population‐specific in humans, representing useful tools for reconstructing the past history of populations with poor historical records. Such lack of information is usually true in the case of recent African‐descent populations of the New World founded by fugitive slaves throughout the slavery period in the Americas, particularly in Brazil, where those communities are known as quilombos. Aiming to recover male‐derived ethnic structure of nine quilombos from the Brazilian Amazon, a total of 300 individuals, belonging to Mazagão Velho (N = 24), Curiaú (N = 48), Mazagão (N = 36), Trombetas (N = 20), Itacoã (N = 22), Saracura (N = 46), Marajó (N = 58), Pitimandeua (N = 26), and Pontal (N = 20), were investigated for nine Y‐STRs (DYS393, DYS19, DYS390, DYS389 I, DYS389 II, DYS392, DYS391, DYS385 I/II). From the 169 distinct haplotypes obtained, 120 were singletons. The results suggest the West African coast as the main origin of slaves brought to Brazil (54% of male contribution); the European contribution was high (41%), while the Amerindian's was low (5%). Those results contrast with previous mtDNA data that showed high Amerindian female contribution (46.6%) in African‐descent populations. AMOVA suggests that the genetic differentiation among the quilombos is mainly influenced by admixture with European. However, when restricting AMOVA to African‐specific haplotypes, low differentiation was detected, suggesting great genetic homogeneity of the African founding populations and/or a later homogenization by intense slave trade inside Brazil. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
2.
Alan Graham 《Brittonia》2003,55(4):357-383
An understanding of the phytogeographic history of a region depends upon an adequate fossil record to reveal migrational histories
and the timing and directions(s) of introductions and extinctions, and to augment or circumvent undue reliance on molecular
clocks. It further depends upon an accurate phylogeny of the taxa to establish real patterns of geographic affinities (phylogeography),
and a relatively detailed geologic history to assess the relative roles of dispersal and vicariance in populating the islands.
For the Greater Antilles new information is slowly emerging on the plant fossil record through study of new floras such as
the Eocene Saramaguacán palynoflora from Cuba, and more is potentially available from the middle Oligocene San Sebastian megafossil
flora of Puerto Rico that has not been revised since the early 1900s. Phylogeographic studies and area cladograms are still
meager for plants, but data from various animal groups are providing a context for the general biotic history of the Antilles.
Perhaps the area of greatest advance is being made in achieving an adequate plate tectonic model for the Caribbean region.
There is now some convergence toward a mobilist model that depicts a Cretaceous volcanic island arc that extended from the
Mexico/Chortis block in the north to Ecuador in the south, and gradually moved through the developing portal between North
and South America to collide with the Bahamas Platform in the middle Eocene. Throughout this 70-million-year history there
was an immensely complex pattern of collision/separation and submergence/emergence that provided opportunity both for vicariance
and dispersal in the migration, evolution, and speciation of the flora of the Greater Antilles. 相似文献
3.
Chakrabarty P 《Molecular phylogenetics and evolution》2006,39(3):619-627
A molecular phylogenetic analysis recovers a pattern consistent with a drift vicariance scenario for the origin of Greater Antillean cichlids. This phylogeny, based on mitochondrial and nuclear genes, reveals that clades on different geographic regions diverged concurrently with the geological separation of these areas. Middle America was initially colonized by South American cichlids in the Cretaceous, most probably through the Cretaceous Island Arc. The separation of Greater Antillean cichlids and their mainland Middle American relatives was caused by a drift vicariance event that took place when the islands became separated from Yucatan in the Eocene. Greater Antillean cichlids are monophyletic and do not have close South American relatives. Therefore, the alternative hypothesis that these cichlids migrated via an Oligocene landbridge from South America is falsified. A marine dispersal hypothesis is not employed because the drift vicariance hypothesis is better able to explain the biogeographic patterns, both temporal and phylogenetic. 相似文献
4.
Lowery RK Herrera KJ Barrett DA Rodriguez R Hadden LR Harutyunyan A Margaryan A Yepiskoposyan L Herrera RJ 《American journal of physical anthropology》2011,146(2):171-178
The archeology and ethnology of Armenia suggest that this region has acted as a crossroads for human migrations from Europe and the Middle East since at least the Neolithic. Near continual foreign influx has, in turn, led to the supposition that the gene pools of geographically separated Armenian populations may have diverged as differing historical influences potentially left distinct genetic traces in the various regions of the Armenian plateau. In this study, we seek to address whether any evidence for such genetic regional partitioning in Armenians exists by analyzing, for the first time, 15 autosomal short tandem repeat (STR) loci in 404 Armenians from four geographically well-characterized collections (Ararat Valley, Gardman, Sasun, and Lake Van) that represent distinct communities from across Historical Armenia. In addition, to determine whether genetic differences among these four Armenian populations are the result of differential affinities to populations of known historical influence in Armenia, we utilize 27 biogeographically targeted reference populations for phylogenetic and admixture analyses. From these examinations, we find that while close genetic affiliations exist between the two easternmost Armenian groups analyzed, Ararat Valley and Gardman, the remaining two populations display substantial distinctions. In particular, Sasun is distinguished by evidence for genetic contributions from Turkey, while a stronger Balkan component is detected in Lake Van, potentially suggestive of remnant genetic influences from ancient Greek and Phrygian populations in this region. 相似文献
5.
Janet Franklin Lucas C. Majure Yuley Encarnacin Teodoro Clase Hodali Almonte‐Espinosa Miguel Landestoy Andrew W. Kratter Jessica A. Oswald Douglas E. Soltis Ryan S. Terrill David W. Steadman 《Biotropica》2019,51(6):802-816
We report the results of systematic vascular plant and bird surveys in Seasonally Dry Tropical Forest (SDTF) across leeward and windward elevation gradients (31–884 masl) in the Sierra Martín García (SMG), Dominican Republic. We expected to see gradual, systematic changes in plant distributions with elevation owing to the strong effect of topoclimate. In contrast, we predicted bird community composition to be related only weakly to elevation, because we expected bird distributions to be more strongly related to vegetation structure than composition. Based on 48 vegetation transects, we identified seven groups that differed in their species composition, which was correlated with elevation and precipitation. The most distinctive vegetation community occurs in dry, warm, and low elevations on the leeward slope, featuring large numbers of non‐woody indicator species (those species found frequently within one group but not in other groups) even though most of its trees and shrubs represent species that are widespread. Low rainfall and shale bedrock (rather than limestone) may be the primary drivers of distinctiveness in the low‐elevation leeward plots. On the leeward slope, where we also surveyed the birds, the vegetation community changes gradually with elevation at mid‐ to high elevations. The most distinctive bird community also was associated with the low‐elevation forest on shale bedrock and was dominated by widespread species. At higher elevations, but still within leeward SDTF, the bird communities had a stronger component of species endemic either to Hispaniola or to Caribbean islands, and species turnover did not correspond to the elevation gradient. Abstract in Spanish is available with online material. 相似文献
6.
Simms TM Wright MR Hernandez M Perez OA Ramirez EC Martinez E Herrera RJ 《American journal of physical anthropology》2012,148(4):618-631
Although previous studies have characterized the genetic structure of populations from Haiti and Jamaica using classical and autosomal STR polymorphisms, the patrilineal influences that are present in these countries have yet to be explored. To address this lacuna, the current study aims to investigate, for the first time, the potential impact of different ancestral sources, unique colonial histories, and distinct family structures on the paternal profile of both groups. According to previous reports examining populations from the Americas, island-specific demographic histories can greatly impact population structure, including various patterns of sex-biased gene flow. Also, given the contrasting autosomal profiles provided in our earlier study (Simms et al.: Am J Phys Anthropol 142 (2010) 49-66), we hypothesize that the degree and directionality of gene flow from Europeans, Africans, Amerindians, and East Asians are dissimilar in the two countries. To test this premise, 177 high-resolution Y-chromosome binary markers and 17 Y-STR loci were typed in Haiti (n = 123) and Jamaica (n = 159) and subsequently utilized for phylogenetic comparisons to available reference collections encompassing Africa, Europe, Asia (East and South), and the New World. Our results reveal that both studied populations exhibit a predominantly South-Saharan paternal component, with haplogroups A1b-V152, A3-M32, B2-M182, E1a-M33, E1b1a-M2, E2b-M98, and R1b2-V88 comprising 77.2% and 66.7% of the Haitian and Jamaican paternal gene pools, respectively. Yet, European derived chromosomes (i.e., haplogroups G2a*-P15, I-M258, R1b1b-M269, and T-M184) were detected at commensurate levels in Haiti (20.3%) and Jamaica (18.9%), whereas Y-haplogroups indicative of Chinese [O-M175 (3.8%)] and Indian [H-M69 (0.6%) and L-M20 (0.6%)] ancestry were restricted to Jamaica. 相似文献
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8.
Yadong Zhou Sichong Chen Guangwan Hu Geoffrey Mwachala Xue Yan Qingfeng Wang 《Ecology and evolution》2018,8(17):8930-8939
Mount Kenya is of ecological importance in tropical east Africa due to the dramatic gradient in vegetation types that can be observed from low to high elevation zones. However, species richness and phylogenetic diversity of this mountain have not been well studied. Here, we surveyed distribution patterns for a total of 1,335 seed plants of this mountain and calculated species richness and phylogenetic diversity across seven vegetation zones. We also measured phylogenetic structure using the net relatedness index (NRI) and the nearest species index (NTI). Our results show that lower montane wet forest has the highest level of species richness, density, and phylogenetic diversity of woody plants, while lower montane dry forest has the highest level of species richness, density, and phylogenetic diversity in herbaceous plants. In total plants, NRI and NTI of four forest zones were smaller than three alpine zones. In woody plants, lower montane wet forest and upper montane forest have overdispersed phylogenetic structures. In herbaceous plants, NRI of Afro‐alpine zone and nival zone are smaller than those of bamboo zone, upper montane forest, and heath zone. We suggest that compared to open dry forest, humid forest has fewer herbaceous plants because of the closed canopy of woody plants. Woody plants may have climate‐dominated niches, whereas herbaceous plants may have edaphic and microhabitat‐dominated niches. We also proposed lower and upper montane forests with high species richness or overdispersed phylogenetic structures as the priority areas in conservation of Mount Kenya and other high mountains in the Eastern Afro‐montane biodiversity hotspot regions. 相似文献
9.
Tropical stream food webs are thought to be based primarily on terrestrial resources (leaf litter) in small forested headwater streams and algal resources in larger, wider streams. In tropical island streams, the dominant consumers are often omnivorous freshwater shrimps that consume algae, leaf litter, insects, and other shrimps. We used stable isotope analysis to examine (1) the relative importance of terrestrial and algal‐based food resources to shrimps and other consumers and determine (2) if the relative importance of these food resources changed along the stream continuum. We examined δ15N and δ13C signatures of leaves, algae, macrophytes, biofilm, insects, snails, fishes, and shrimps at three sites (300, 90, and 10 m elev.) along the Río Espíritu Santo, which drains the Caribbean National Forest, Puerto Rico. Isotope signatures of basal resources were distinct at all sites. Results of two‐source δ13C mixing models suggest that shrimps relied more on algal‐based carbon resources than terrestrially derived resources at all three sites along the continuum. This study supports other recent findings in tropical streams, demonstrating that algal‐based resources are very important to stream consumers, even in small forested headwater streams. This study also demonstrates the importance of doing assimilation‐based analysis (i.e., stable isotope or trophic basis of production) when studying food webs. 相似文献
10.
Alarista succina gen. et sp. nov. (Poaceae) is described from a single floret preserved in amber of Tertiary age originating from the Dominican Republic. The new genus is characterised by (1) a narrow-winged lemma awn, (2) numerous (as many as 17) lemma nerves, (3) a lengthy rachilla internode (implying a lax spikelet), (4) sinuous-margined long cells, (5) silica cells arranged transversely, (6) stomatal subsidiaries low domed and (7) papillae. The epidermal features are characteristic of the abaxial leaf blade surface of members of the Bambusoideae and the fossil is placed in this group. htp://zoobank.org/033FCBF4-CD61-4C85-97E4-8418C9ABA5E6 相似文献
11.
Forest recovery in abandoned agricultural lands in a karst region of the Dominican Republic 总被引：4，自引：0，他引：4
This study documents the status of forest vegetation in the karst region of Los Haitises National Park, Dominican Republic, following the abandonment of pastures (5 years), young (5 years) `conucos' (mixed plantings), old (7–30 years) conucos, and cacao plantations (>25 years). We compared these sites to vegetation characteristics of patches of forest in karst valleys (`old forest'–too old to know their exact land use) and on mogote tops with no recent history of human disturbance. The youngest sites date to when squatters were removed from Los Haitises National Park. Forest structure (density, basal area, and species richness of woody plants 1 cm DBH) were all significantly affected by land use. Density was highest in intermediate-aged valley sites (old conucos) and mogote tops, while both basal area and species richness tended to increase with age of abandonment. Although cacao plantations had been abandoned for more than 25 years the species diversity was low, due to continued regeneration of this persistent crop. Abandoned pastures had the greatest nonwoody biomass and were dominated by the fern Nephrolepis multiflora which had completely replaced pasture grasses. An ordination of the woody plant communities separated the mogote tops from valleys, emphasizing the strong control that topography has on the forest community in moist and wet tropical forests on karst substrates. Valley sites were arranged in the ordination in order of their age, suggesting a successional sequence converging on the composition of the `old forest' sites. 相似文献
12.
Aim This work examines whether the history of diversification of Amphiacusta (Orthoptera, Gryllidae) in the Caribbean corresponds to a vicariant or a dispersalist model. Location The Greater Antillean islands of the Caribbean region. Methods The phylogenetic relationships among species were estimated using a procedure that directly estimates the underlying species tree from independent loci (in this case, one mitochondrial and one nuclear locus). This tree was then used to test for topological congruence with a vicariant model, and to estimate divergence times. Results The analyses based on the expected pattern of species divergence (i.e. species‐tree topology) support a vicariant model. With the notable exception of a dispersal event marking the colonization of Jamaica, the timing of the events are generally consistent with a vicariant scenario, given the current taxon sampling and potential errors with dating the divergence events. Main conclusions The tendency of species to co‐segregate by island suggests that intra‐island diversification is common. Despite their flightlessness, species of Amphiacusta are apparently capable of long‐distance dispersal, such as colonization from the Puerto Rican/Virgin Island bank to Jamaica. The topology of the species tree is consistent with a vicariant model of divergence, and the dates of divergence between island groups are generally consistent with an island–island vicariance model. A strict island–island vicariance scenario can, however, be rejected because of inferred dispersal events such as the colonization of Jamaica. Nevertheless, the biogeographic tests suggest that most of the diversity was generated under a combination of intra‐island diversification and island–island vicariance. Additional sampling of taxa will be needed to verify this hypothesized scenario. Our findings indicate that Amphiacusta presents an ideal opportunity for examining the role of sexual selection in promoting diversification, which would complement the large number of studies focused on adaptive divergence of Caribbean taxa. 相似文献
13.
Lizards in the genus Anolis have experienced adaptive radiation in the Greater Antilles, producing a suite of species morphologically adapted to use different parts of the environment. In the Lesser Antilles, adaptive radiation has not occurred, but on some islands, interpopulational variation is high and represents adaptation to different habitats. We compared the extent of morphological differentiation among Greater Antillean habitat specialists with that exhibited among populations of two species, Anolis marmoratus and A. oculatus, from the Lesser Antillean islands of Guadeloupe and Dominica. Although extensive, intraspecific divergence in the Lesser Antilles is substantially less in magnitude than the differences among habitat specialists in the Greater Antilles. All populations of A. marmoratus are most similar to Greater Antillean trunk‐crown habitat specialists, but populations of A. oculatus differ in their affinities: some are similar to trunk‐crown anoles, but others are more similar to trunk‐ground habitat specialists. 相似文献
14.
Christophe Vieira Kathleen Morrow Sofie D'Hondt Olga Camacho Aschwin H. Engelen Claude E. Payri Olivier De Clerck 《Journal of phycology》2020,56(3):592-607
Distributed in tropical and warm-temperate waters worldwide, Lobophora species are found across the Greater Caribbean (i.e., Caribbean sensu stricto, Gulf of Mexico, Florida, the Bahamas, and Bermuda). We presently discuss the diversity, ecology, biogeography, and evolution of the Greater Caribbean Lobophora species based on previous studies and an extensive number of samples collected across the eastern, southern, and to a lesser extent western Caribbean. A total of 18 Lobophora species are now documented from the Greater Caribbean, of which five are newly described (L. agardhii sp. nov., L. dickiei sp. nov., L. lamourouxii sp. nov., L. richardii sp. nov., and L. setchellii sp. nov.). Within the Greater Caribbean, the eastern Caribbean and the Central Province are the most diverse ecoregion and province (16 spp.), respectively. Observed distribution patterns indicate that Lobophora species from the Greater Caribbean have climate affinities (i.e., warm-temperate vs. tropical affinities). In total, 11 Lobophora species exclusively occur in the Greater Caribbean; six are present in the western Atlantic; two in the Indo-Pacific; and one in the eastern Pacific. Biogeographic analyses support that no speciation occurred across the Isthmus of Panama, and that the Greater Caribbean acted as a recipient region for species from the Indo-Pacific and as a region of diversification as well as a donor region to the North-eastern Atlantic. The Greater Caribbean is not an evolutionary dead end for Lobophora, but instead generates and exports diversity. Present results illustrate how sampling based on DNA identification is reshaping biogeographic patterns, as we know them. 相似文献
15.
The nymphs of Antillotolania Ramos and Deiroderes Ramos are described for the first time, along with the first host record for the genus Antillotolania, represented by Antillotolania myricae, sp. n. Nymphal features of both genera, such as a ventrally fused, cylindrical tergum IX (anal tube), the presence of abdominal lamellae, and heads with foliaceous ventrolateral lobes confirm their placement in Membracidae and are consistent with phylogenetic analyses placing them in Stegaspidinae but in conflict with a cladistic analysis showing a closer relationship to Nicomiinae. Head processes and emarginate forewing pads in the last instars of both genera support an earlier estimate, based on nuclear genes, that the two genera form a monophyletic group in Stegaspidinae. Distinguishing features of the four species of Antillotolania are tabulated. 相似文献
16.
Three species ofBactris are recognized in the Greater Antilles:B. cubensis (from Cuba),B. plumeriana (from Hispaniola), andB. jamaicana (from Jamaica). A cladistic analysis of the non-ocreate clade—i.e.,Bactris cubensis, B. plumeriana, B. jamaicana, B. macana, andB. gasipaes—confirmed that the Greater Antillean species ofBactris form a monophyletic group, i.e., the Antillean clade. Synapomorphies supporting the Antillean clade are mesocarp and endocarp fibers numerous, parallel, predominantly narrow, few broad, extending the entire length of the endocarp; and leaf segments 45–80 per side of rachis. The presence of fiber-sclereids in the leaf lamina, and petals of the staminate flowers ovate to ovatetrullate, with sparsely branched fibers, may represent additional synapomorphies.Bactris plumeriana andB. jamaicana are hypothesized to be sister species, a grouping weakly supported by their short anthers. Each species has at least one autapomorphy; therefore, all are considered to be a cladospecies. Noteworthy interpopulational variation occurs withinBactris plumeriana andB. cubensis. 相似文献
17.
Lasiocroton trelawniensis (Euphorbiaceae), a critically endangered species from the Cockpit Country of Jamaica, belongs to Bernardia (Euphorbiaceae). Botanical Review Vol. 74, No., 1 2008.—A taxonomic study based on scanning electron microscopy of pollen, macro-morphology, and a molecular phylogenetic analysis of the chloroplast DNA regions trnL-F and rbcL shows that Lasiocroton trelawniensis belongs to the Neotropical genus Bernardia. The main morphological differences between Bernardia and Lasiocroton are given, and the new combination Bernardia trelawniensis is provided.
Resumen Un estudio taxonómico basado en microscopía electrónica de barrido del polen, en macro-morfología, y en análisis filogenéticos moleculares de las regiones del ADN de los cloroplastos trnL-F y rbcL muestra que Lasiocroton trelawniensis pertenece al género neotropical Bernardia. Se dan las principales diferencias morfológicas entre Bernardia y Lasiocroton y se da así mismo la nueva combinación Bernardia trelawniensis.相似文献
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19.
George K. Rogers 《Brittonia》2000,52(3):218-233
The genusAgave (Agavaceae) is revised taxonomically for the Lesser Antilles. All 12 previously recognized species are placed into synonymy underAgave karatto Miller. A neotype is selected for the nameAgave karatto, and lectotypes are designated forA. barbadensis Trel.,A. medioxima Trel.,A. obducta Trel.,A. vangrolae Trel., andA. ventum-versa Trel. Specimens are cited for most of the Lesser Antillean islands. That the Caribbean agaves are similar to the MexicanAgave nayaritensis Gentry is supported. The hypothesis that the pattern of partial sterility, clonality, and minimal morphological differentiation of the Lesser Antillean agaves is related to prehistoric human activity is developed based on similar patterns among mainland agaves and historical information. Uses for the archaeological “Barbados shell tool” may have included decorticating agave leaves for fiber extraction. 相似文献
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