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Kenneth J. Sytsma - One of the best experts on this subject based on the ideXlab platform.
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historical biogeography and life history evolution of andean puya Bromeliaceae
Botanical Journal of the Linnean Society, 2013Co-Authors: Rachel S Jabaily, Kenneth J. SytsmaAbstract:Puya (Bromeliaceae), with > 200 species, is a classic example of a recent, rapid species-level radiation in the Andes. To assess the biogeographical history of this primarily Andean species group and the evolution of different life histories, amplified fragment length polymorphism (AFLP) data were generated for 75 species from throughout the geographical range of the genus. Distribution data for latitudinal and elevational ranges were compiled for almost all species. The greatest number of species is found at mid-elevations and mid-latitudes south of the equator. The genus originated in central Chile and first moved into the Cordillera Oriental of the central Andes via inter-Andean valleys. Cladogenesis progressed in a general south to north direction tracking the final uplift of the Andes. All taxa north of the Western Andean Portal form a monophyletic group implying a single colonization of the northern Andes, with no subsequent transitions back south from the Northern Andes. Repeated evolutionary transitions of lineages up and down in elevation are suggestive of allopatric speciation driven by Pleistocene glaciation cycles. True semelparity evolved once in P. raimondii, with similar semi-semelparity evolving repeatedly in paramos of the northern Andes. Fieldwork and phylogenetic characterization of high-elevation Puya are priorities for future efforts. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ●●, ●●–●●.
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phylogenetics of puya Bromeliaceae placement major lineages and evolution of chilean species
American Journal of Botany, 2010Co-Authors: Rachel S Jabaily, Kenneth J. SytsmaAbstract:Puya (Bromeliaceae), a large genus of terrestrial bromeliads found throughout a range of elevations in the Andes and central Chile, is of great systematic, evolutionary, and biogeographical interest. This fi rst molecular phylogenetic study of Puya and related bromeliads employs matK , trnS-trnG , rps16 , and PHYC sequences. Chloroplast DNA, nuclear DNA, and combined DNA data all place Puya closest to subfamily Bromelioideae. Nuclear and combined data support Puya as monophyletic, and the two subgenera are nonmonophyletic. All data indicate that the Chilean species of Puya are early diverging within the genus, consistent with Chilean genera as the fi rst-diverging members of subfamily Bromelioideae. Central Chile is identifi ed as a key region for understanding the biogeographical history of Bromeliaceae, as is true with other South American plant groups. A complicated history involving early chloroplast capture and later secondary hybridization and/or introgression is seen in Chilean lineages. These events help explain the occurrence of sterile infl orescence tips, fl oral color and shape, and leaf indument. The ecological radiation of Puya appears coincident with the fi nal, recent rise of the Andes and subsequent high-elevation habitat diversifi cation. Additionally, geographical distribution, rather than moisture or elevational adaptations, correlates to species relationships. Evolution of CAM photosynthesis has occurred multiple times.
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ancient vicariance or recent long distance dispersal inferences about phylogeny and south american african disjunctions in rapateaceae and Bromeliaceae based on ndhf sequence data
International Journal of Plant Sciences, 2004Co-Authors: Thomas J. Givnish, Kendra C. Millam, Timothy M. Evans, Jocelyn C. Hall, Paul E. Berry, Chris J Pires, Kenneth J. SytsmaAbstract:Rapateaceae and Bromeliaceae each have a center of diversity in South America and a single species native to a sandstone area in west Africa that abutted the Guayana Shield in northern South America before the Atlantic rifted. They thus provide ideal material for examining the potential role of vicariance versus long-distance dispersal in creating amphiatlantic disjunctions. Analyses based on ndhF sequence variation indicate that Rapateaceae and Bromeliaceae are each monophyletic and underwent crown radiation around 41 and 23 Ma, respectively. Both exhibit clocklike sequence evolution, with bromeliads evolving roughly one-third more slowly than rapateads. Among rapateads, the divergence of west African Maschalocephalus dinklagei from its closest South American relatives implies that Maschalocephalus resulted via long-distance dispersal 7 Ma, not ancient continental drift; only its sandstone habitat is vicariant. Rapateads arose first at low elevations in the Guayana Shield; the earliest divergent genera are widespread along riverine corridors there and, to a lesser extent, in Amazonia and the Brazilian Shield. Speciation at small spatial scales accelerated 15 Ma with the invasion of high-elevation, insular habitats atop tepuis. Among bromeliads, Pitcairnia feliciana diverges little from its congeners and appears to be the product of long-distance dispersal ca. 12 Ma. Brocchinia/Ayensua and then Lindmania are sister to all other bromeliads, indicating that the Guayana Shield was also the cradle of the bromeliads. Three lineages form an unresolved trichotomy representing all other bromeliads: (1) Tillandsioideae, (2) Hechtia, and (3) a large clade including remaining genera of Pitcairnioideae and all Bromelioideae. The last includes a clade of pitcairnioid genera endemic to the Guayana and Brazilian Shields; a xeric group (Abromeitiella/Deuterocohnia/Dyckia/Encholirium/Fosterella) from southern South America and the southern Andes, sister to Pitcairnia; and Andean Puya, sister to Bromelioideae, with many of the latter native to the Brazilian Shield. Both Rapateaceae and Bromeliaceae appear to have arisen at low elevations in the Guayana Shield, experienced accelerated speciation after invading dissected mountainous terrain, and undergone long-distance dispersal to west Africa recently. Bromeliad acquisition of key adaptations to drought (e.g., CAM photosynthesis, tank habit, tillandsioid leaf trichomes) 17 Ma appears to have coincided with and help cause the centripetal invasion of drier, more seasonal regions beyond the Guayana Shield, resulting in a wider familial range and dominance of the epiphytic adaptive zone. Geology, past and present climate, and proximity to South America help account for both families occurring in nearly the same area of Africa. We present a new classification for Rapateaceae, including a new tribe Stegolepideae, a new subfamily Monotremoideae, and revisions to tribe Saxofridericieae and subfamily Rapateoideae.
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ancient vicariance or recent long distance dispersal inferences about phylogeny and south american african disjunctions in rapateaceae and Bromeliaceae based on ndhf sequence data
International Journal of Plant Sciences, 2004Co-Authors: Thomas J. Givnish, Kendra C. Millam, Timothy M. Evans, Jocelyn C. Hall, Paul E. Berry, Chris J Pires, Kenneth J. SytsmaAbstract:Rapateaceae and Bromeliaceae each have a center of diversity in South America and a single species native to a sandstone area in west Africa that abutted the Guayana Shield in northern South America before the Atlantic rifted. They thus provide ideal material for examining the potential role of vicariance versus long‐distance dispersal in creating amphiatlantic disjunctions. Analyses based on ndhF sequence variation indicate that Rapateaceae and Bromeliaceae are each monophyletic and underwent crown radiation around 41 and 23 Ma, respectively. Both exhibit clocklike sequence evolution, with bromeliads evolving roughly one‐third more slowly than rapateads. Among rapateads, the divergence of west African Maschalocephalus dinklagei from its closest South American relatives implies that Maschalocephalus resulted via long‐distance dispersal 7 Ma, not ancient continental drift; only its sandstone habitat is vicariant. Rapateads arose first at low elevations in the Guayana Shield; the earliest divergent genera a...
Olaf Malm - One of the best experts on this subject based on the ideXlab platform.
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assessment of heavy metals in the particulate matter of two brazilian metropolitan areas by using tillandsia usneoides as atmospheric biomonitor
Environmental Science and Pollution Research, 2011Co-Authors: Nelzair Vianna, Daniel Neves Schmitz Goncalves, Flavia R Brandao, Roberta P De Barros, Gilberto Amado M Filho, Rodrigo Ornellas Meire, Joao Paulo Machado Torres, Olaf Malm, Argemiro Doliveira, Leonardo R AndradeAbstract:Purpose The aims of this paper were to quantify the heavy metals (HM) in the air of different sites in Rio de Janeiro (RJ) and Salvador (SA) using Tillandsia usneoides (Bromeliaceae) as a biomonitor, and to study the morphology and elemental composition of the air particulate matter (PM) retained on the Tillandsia surface.
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hg localisation in tillandsia usneoides l Bromeliaceae an atmospheric biomonitor
Atmospheric Environment, 2002Co-Authors: G Amado M Filho, Leonardo R Andrade, Marcos Farina, Olaf MalmAbstract:Abstract The Spanish moss, Tillandsia usneoides , has been applied as an atmospheric biomonitor of Hg contamination, although the mechanism of metal plant accumulation has not been understood until now. In the present work, analytical scanning electron microscopy (SEM) was used to localize Hg in T. usneoides exposed to a Hg–air-contaminated area during 15 days. After this period, Hg was determined by the flow injection mercury system, and plants were prepared for SEM observation and energy-dispersive X-ray analysis. A concentration of 2702±318 μg Hg g −1 was determined in exposed plants. The presented microanalytical results demonstrated that Hg was partly associated with atmospheric particles deposited upon the plant surface, but it was highly absorbed by the scales, stem and leaves surfaces and less absorbed by epidermal cells of T. usneoides . No Hg was detected in mesophyll parenchyma or in vascular system cells. The great surface adsorption area provided by the scales, in addition to the characteristics of T. usneoides morphology, especially of the node region, are suggested to confer the great capability of T. usneoides in Hg holding.
Georg Zizka - One of the best experts on this subject based on the ideXlab platform.
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ecological range shift in the polyploid members of the south american genus fosterella Bromeliaceae
Annals of Botany, 2017Co-Authors: Juraj Paule, Georg Zizka, Natascha Wagner, Kurt WeisingAbstract:Background and Aims The distribution of polyploidy along a relatively steep Andean elevation and climatic gradient is studied using the genus Fosterella L.B. Sm. (Bromeliaceae) as a model system. Ecological differentiation of cytotypes and the link of polyploidy with historical biogeographic processes such as dispersal events and range shift are assessed. Methods 4',6-Diamidino-2-phenylindole (DAPI) staining of nuclei and flow cytometry were used to estimate the ploidy levels of 159 plants from 22 species sampled throughout the distribution range of the genus. Ecological differentiation among ploidy levels was tested by comparing the sets of climatic variables. Ancestral chromosome number reconstruction was carried out on the basis of a previously generated phylogeographic framework. Key Results This study represents the first assessment of intrageneric, intraspecific and partially intrapopulational cytotype diversity in a genus of the Bromeliaceae family. In Fosterella , the occurrence of polyploidy was limited to the phylogenetically isolated penduliflora and rusbyi groups. Cytotypes were found to be ecologically differentiated, showing that polyploids preferentially occupy colder habitats with high annual temperature variability (seasonality). The combined effects of biogeographic history and adaptive processes are presumed to have shaped the current cytotype distribution in the genus. Conclusions The results provide indirect evidence for both adaptive ecological and non-adaptive historical processes that jointly influenced the cytotype distribution in the predominantly Andean genus Fosterella (Bromeliaceae). The results also exemplify the role of polyploidy as an important driver of speciation in a topographically highly structured and thus climatically diverse landscape.
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chromosome numbers and dna content in Bromeliaceae additional data and critical review
Botanical Journal of the Linnean Society, 2014Co-Authors: Georg Zizka, Katharina Schulte, Jailson Gitai, Juraj Paule, Ana Maria BenkoisepponAbstract:For the large Neotropical plant family Bromeliaceae, we provide new data on chromosome numbers, cytological features and genome size estimations, and combine them with data available in the literature. Root-tip chromosome counts for 46 species representing four subfamilies and a literature review of previously published data were carried out. Propidium iodide staining and flow cytometry were used to estimate absolute genome sizes in five subfamilies of Bromeliaceae, sampling 28 species. Most species were diploid with 2n = 50 in Bromelioideae, Puyoideae and Pitcairnioideae, followed by 2n = 48 observed mainly in Tillandsioideae. Individual chromosome sizes varied more than tenfold, with the largest chromosomes observed in Tillandsioideae and the smallest in Bromelioideae. Genome sizes (2C-values) varied from 0.85 to 2.23 pg, with the largest genomes in Tillandsioideae. Genome evolution in Bromeliaceae relies on two main mechanisms: polyploidy and dysploidy. With the exception of Tillandsioideae, polyploidy is positively correlated with genome size. Dysploidy is suggested as the mechanism responsible for the generation of the derived chromosome numbers, such as 2n = 32/34 or 2n = 48. The occurrence of B chromosomes in the dysploid genus Cryptanthus suggests ongoing speciation processes closely associated with chromosome rearrangements. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176, 349–368.
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Chilean Bromeliaceae: diversity, distribution and evaluation of conservation status
Biodiversity and Conservation, 2009Co-Authors: Georg Zizka, Marco Schmidt, Katharina Schulte, Patricio Novoa, Raquel Pinto, Konstantin KönigAbstract:Chile is home to 23 species of Bromeliaceae, including 2 subspecies and 4 varieties. Twenty species are endemic to the country. We examined 883 herbarium specimens from 27 herbaria for our treatment of the Bromeliaceae for the “Flora de Chile”. These data and field observations resulted in a comprehensive database that we used to generate distribution maps for each species. We applied ecological niche modelling to reveal distribution areas and centers of Bromeliaceae diversity. We further analysed the collecting dates of the herbarium specimens to assess possible changes in species abundance. In this study we assess the conservation status of the bromeliad species in Chile. IUCN categories were assigned to the 27 bromeliad taxa as follows: Critically endangered: 4, Endangered: 6, Vulnerable: 11, Near threatened: 2, Least concern: 4. No species has become “Extinct” up to now. We also put forth a hypothesis about their biogeographic history.
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multi locus plastid phylogeny of bromelioideae Bromeliaceae and the taxonomic utility of petal appendages and pollen characters
Candollea, 2008Co-Authors: Katharina Schulte, Georg ZizkaAbstract:SCHULTE ,K.&G. ZIZKA (2008).MultilocusplastidphylogenyofBrome - lioideae(Bromeliaceae) andthetaxonomicutilityofpetalappendagesand pollencharacters . Candollea 63:209-225.InEnglish,EnglishandFrench abstracts. Forthefirsttimeamolecularphylogenybasedonfiveplastid markersispresentedforsubfamily Bromelioideae (Bromeli - aceae) . The species set includes 40 genera / 81 species of Bromeliaceae representingallsubfamilies: Bromelioideae (29 genera/58 species ), Tillandsioideae (6 genera/8 species)and Pitcairnioideae s.l.(5genera/14 species).Basalcladesamong the Bromelioideae are identified, nevertheless the "Core Bromelioids"comprisingthemajorityofthespeciesdisplay lowresolution.Thephylogenyobtainedmakesevident,that thegenericconceptfor Aechmea Ruiz&Pav.anditsallied taxadoesnotdescribemonophyleticgroups.Thesameholds trueforseveralsubgeneraof Aechmea. Thephylogenyallows theassessmentofthesystematicvalueoftwocharactersthat havebeenregardedassystematicvaluableforgenericdelim - itationinthe(sub)family,1)thepetalappendagesand2)the pollenmorphology.Basal Bromelioideae arecharacterizedby sulcatepollen,whilethemorederived Bromelioideae display threedifferentpollentypesandseveraltransitionsbetweenthe characterstates.
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systematics of bromelioideae Bromeliaceae evidence from molecular and anatomical studies
Aliso, 2007Co-Authors: Ralf Horres, Kurt Weising, Katharina Schulte, Georg ZizkaAbstract:A reconstruction of the phylogeny of Bromeliaceae based on sequence data from three noncoding chloroplast DNA markers (trnL intron, trnT-trnL, and trnT-trnF intergenic spacer [IGS]) is presented, including 26 genera and 33 species. Relationships of Bromelioideae and phylogeny within this subfamily were analyzed in more detail on the basis of two of these markers (trnL intron and trnL-trnF IGS) using a set of 37 genera/74 species of Bromeliaceae, including 28 genera/60 species of Bromelioideae. Sister group relationships of Bromelioideae were not resolved with sufficient reliability, but the most likely candidates are the genera Fosterella and Puya. The basal phylogeny of Bromelioideae also was not resolved. Greigia, Ochagavia/Fascicularia/Fernseea, Deinacanthon, Bromelia, and a "core group" of the remaining Bromelioideae formed a basal polytomy. Within Bromelioideae, the AFLP technique was applied to assess relationships among selected groups of genera. In the Ochagavia/Fascicularia group (5 species and subspecies/16 accessions), AFLP data fully confirmed the systematic relationships based on morphological and anatomical characters. Investigation of 30 Aechmea species (33 accessions), including all subgenera and one species each from the related genera Ursulaea, Portea, Chevaliera, and Streptocalyx produced no resolution for several of the species. Clades that received good bootstrap support generally did not correspond with the delimitation of subgenera of Aechmea. Additionally, leaf blade anatomy of these species was investigated. The results corresponded partly with those of the AFLP analysis. Generic rank for Ursulaea and Portea was not supported.
Leonardo R Andrade - One of the best experts on this subject based on the ideXlab platform.
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assessment of heavy metals in the particulate matter of two brazilian metropolitan areas by using tillandsia usneoides as atmospheric biomonitor
Environmental Science and Pollution Research, 2011Co-Authors: Nelzair Vianna, Daniel Neves Schmitz Goncalves, Flavia R Brandao, Roberta P De Barros, Gilberto Amado M Filho, Rodrigo Ornellas Meire, Joao Paulo Machado Torres, Olaf Malm, Argemiro Doliveira, Leonardo R AndradeAbstract:Purpose The aims of this paper were to quantify the heavy metals (HM) in the air of different sites in Rio de Janeiro (RJ) and Salvador (SA) using Tillandsia usneoides (Bromeliaceae) as a biomonitor, and to study the morphology and elemental composition of the air particulate matter (PM) retained on the Tillandsia surface.
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hg localisation in tillandsia usneoides l Bromeliaceae an atmospheric biomonitor
Atmospheric Environment, 2002Co-Authors: G Amado M Filho, Leonardo R Andrade, Marcos Farina, Olaf MalmAbstract:Abstract The Spanish moss, Tillandsia usneoides , has been applied as an atmospheric biomonitor of Hg contamination, although the mechanism of metal plant accumulation has not been understood until now. In the present work, analytical scanning electron microscopy (SEM) was used to localize Hg in T. usneoides exposed to a Hg–air-contaminated area during 15 days. After this period, Hg was determined by the flow injection mercury system, and plants were prepared for SEM observation and energy-dispersive X-ray analysis. A concentration of 2702±318 μg Hg g −1 was determined in exposed plants. The presented microanalytical results demonstrated that Hg was partly associated with atmospheric particles deposited upon the plant surface, but it was highly absorbed by the scales, stem and leaves surfaces and less absorbed by epidermal cells of T. usneoides . No Hg was detected in mesophyll parenchyma or in vascular system cells. The great surface adsorption area provided by the scales, in addition to the characteristics of T. usneoides morphology, especially of the node region, are suggested to confer the great capability of T. usneoides in Hg holding.
Jamie Males - One of the best experts on this subject based on the ideXlab platform.
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concerted anatomical change associated with crassulacean acid metabolism in the Bromeliaceae
Functional Plant Biology, 2018Co-Authors: Jamie MalesAbstract:Crassulacean acid metabolism (CAM) is a celebrated example of convergent evolution in plant ecophysiology. However, many unanswered questions surround the relationships among CAM, anatomy and morphology during evolutionary transitions in photosynthetic pathway. An excellent group in which to explore these issues is the Bromeliaceae, a diverse monocot family from the Neotropics in which CAM has evolved multiple times. Progress in the resolution of phylogenetic relationships among the bromeliads is opening new and exciting opportunities to investigate how evolutionary changes in leaf structure has tracked, or perhaps preceded, photosynthetic innovation. This paper presents an analysis of variation in leaf anatomical parameters across 163 C3 and CAM bromeliad species, demonstrating a clear divergence in the fundamental aspects of leaf structure in association with the photosynthetic pathway. Most strikingly, the mean volume of chlorenchyma cells of CAM species is 22 times higher than that of C3 species. In two bromeliad subfamilies (Pitcairnioideae and Tillandsioideae), independent transitions from C3 to CAM are associated with increased cell succulence, whereas evolutionary trends in tissue thickness and leaf air space content differ between CAM origins. Overall, leaf anatomy is clearly and strongly coupled with the photosynthetic pathway in the Bromeliaceae, where the independent origins of CAM have involved significant anatomical restructuring.
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economic and hydraulic divergences underpin ecological differentiation in the Bromeliaceae
Plant Cell and Environment, 2018Co-Authors: Jamie Males, Howard GriffithsAbstract:Leaf economic and hydraulic theories have rarely been applied to the ecological differentiation of speciose herbaceous plant radiations. The role of character trait divergences and network reorganization in the differentiation of the functional types in the megadiverse Neotropical Bromeliaceae was explored by quantifying a range of leaf economic and hydraulic traits in 50 diverse species. Functional types, which are defined by combinations of C3 or Crassulacean acid metabolism (CAM) photosynthesis, terrestrial or epiphytic habits, and non-specialized, tank-forming or atmospheric morphologies, segregated clearly in trait space. Most classical leaf economic relationships were supported, but they were weakened by the presence of succulence. Functional types differed in trait-network architecture, suggesting that rewiring of trait-networks caused by innovations in habit and photosynthetic pathway is an important aspect of ecological differentiation. The hydraulic data supported the coupling of leaf hydraulics and gas exchange, but not the hydraulic safety versus efficiency hypothesis, and hinted at an important role for the extra-xylary compartment in the control of bromeliad leaf hydraulics. Overall, our findings highlight the fundamental importance of structure-function relationships in the generation and maintenance of ecological diversity.
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think tank water relations of Bromeliaceae in their evolutionary context
Botanical Journal of the Linnean Society, 2016Co-Authors: Jamie MalesAbstract:Water relations represent a pivotal nexus in plant biology due to the multiplicity of functions affected by water status. Hydraulic properties of plant parts are therefore likely to be relevant to evolutionary trends in many taxa. Bromeliaceae encompass a wealth of morphological, physiological and ecological variations and the geographical and bioclimatic range of the family is also extensive. The diversification of bromeliad lineages is known to be correlated with the origins of a suite of key innovations, many of which relate directly or indirectly to water relations. However, little information is known regarding the role of change in morphoanatomical and hydraulic traits in the evolutionary origins of the classical ecophysiological functional types in Bromeliaceae or how this role relates to the diversification of specific lineages. In this paper, I present a synthesis of the current knowledge on bromeliad water relations and a qualitative model of the evolution of relevant traits in the context of the functional types. I use this model to introduce a manifesto for a new research programme on the integrative biology and evolution of bromeliad water-use strategies. The need for a wide-ranging survey of morphoanatomical and hydraulic traits across Bromeliaceae is stressed, as this would provide extensive insight into structure–function relationships of relevance to the evolutionary history of bromeliads and, more generally, to the evolutionary physiology of flowering plants.
