Abstract:
:In volume 97(2) of the American Journal of Botany (pp. 268-275), we published an article entitled "Structural, physiological, and stable carbon isotopic evidence that the enigmatic Paleozoic fossil Prototaxites formed from rolled liverwort mats". Here, we respond to a letter and a commentary on our article in the present issue, welcoming this opportunity to continue the scientific dialogue about an issue that has long been stimulating and controversial. For the reader's benefit, we first briefly describe the recent scholarly context of our article.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Graham LE,Cook ME,Hanson DT,Pigg KB,Graham JMdoi
10.3732/ajb.1000172subject
Has Abstractpub_date
2010-07-01 00:00:00pages
1079-86issue
7eissn
0002-9122issn
1537-2197pii
97/7/1079journal_volume
97pub_type
杂志文章abstract:PREMISE:Most plants interact with mycorrhizal fungi and animal pollinators simultaneously. Yet, whether mycorrhizae affect traits important to pollination remains poorly understood and may depend on the match between host and fungal genotypes. Here, we examined how ericoid mycorrhizal fungi affected flowering phenology...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1372
更新日期:2019-11-01 00:00:00
abstract::We assessed the effects of local environment on survival, growth, and development in six clones (genotypes) of Vallisneria americana grown at five sites in the Huron-Erie Corridor. Detrimental effects of local environment on plant performance (rate of clonal growth, leaf and root production, surface area of leaves and...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-12-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:The Malpighiaceae include ∼1300 tropical flowering plant species in which generic definitions and intergeneric relationships have long been problematic. The goals of our study were to resolve relationships among the 11 generic segregates from the New World genus Mascagnia, test the mon...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000146
更新日期:2010-12-01 00:00:00
abstract::Patterns of biodiversity are ultimately the product of speciation and extinction. Speciation serves as the biodiversity pump while extinction serves as the agent that culls global to local levels of biodiversity. Linking these central processes to global and local patterns of biodiversity is a key challenge in both ec...
journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1000289
更新日期:2011-03-01 00:00:00
abstract:PREMISE:Despite the fast pace of exploration of the patterns and processes influencing Neotropical plant hyperdiversity, the taxa explored are mostly from large groups that are widely distributed, morphologically diverse, or economically important. Vochysiaceae is an example of an undersampled taxon, providing an excel...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1502
更新日期:2020-07-01 00:00:00
abstract::The utility of the PCR-based AFLP technique (polymerase chain reaction; amplified fragment length polymorphisms) was explored in elucidating details of polyploid evolution in the Eurasian orchid genus Dactylorhiza. We emphasized Swedish taxa but also included some material from the British Isles and elsewhere in Europ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-10-01 00:00:00
abstract::Seedling establishment has long been believed to be rare on alpine tundra because of predicted life history trade-offs, the clonality of alpine species, and the harshness of the alpine climate. Contrary to the idea that seedlings are rare on alpine tundra, a 4-yr demographic study of seedlings at Niwot Ridge, Colorado...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.8.1197
更新日期:2003-08-01 00:00:00
abstract:PREMISE:Adaptation to harsh edaphic substrates has repeatedly led to the evolution of edaphic specialists and generalists. Yet, it is unclear what factors promote specialization versus generalization. Here, we search for habitat use patterns associated with serpentine endemics (specialists) and serpentine tolerators (g...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1285
更新日期:2019-05-01 00:00:00
abstract::Multiply sired fruits provide unambiguous evidence that pollen from two or more donors was deposited on a stigma and successfully fertilized ovules. Such multiple paternity within fruits can have important consequences for both parental and offspring fitness, but little is known about the frequency of multiple paterni...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.5.885
更新日期:2005-05-01 00:00:00
abstract::Floral morphology of the 13 species of Moringa ranges from actinomorphic flowers with little hypanthium to highly zygomorphic flowers with well-developed hypanthia. Scanning electron and light microscopy were used to identify ontogenetic differences among two actinomorphic and eight zygomorphic species. All species sh...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.1.49
更新日期:2003-01-01 00:00:00
abstract::Ontogenetic trends in the wood structure of Nepalese Rhododendron were studied in 15 specimens of two tree and four subtree species. Average growth ring width was constant from pith to bark in spite of occurrences of extremely narrow, false, or discontinuous rings. Vessel density, vessel area, vessel element length, a...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-04-01 00:00:00
abstract:UNLABELLED:• PREMISE OF THE STUDY:Floral traits play important roles in pollinator attraction and defense against floral herbivory. However, plants may experience trade-offs between conspicuousness to pollinators and herbivore attraction. Comparative studies provide an excellent framework to examine the role of multip...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400171
更新日期:2014-08-01 00:00:00
abstract::Seed mass is considered to be the least plastic component of reproductive yield. Yet, in invasive populations of garlic mustard, Alliaria petiolata, seed mass was highly variable (eightfold among populations, 2.5-7.5 fold within populations, two-threefold within individuals, and 1.4-1.8 fold within fruits). Variation ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-01-01 00:00:00
abstract:PREMISE OF THE STUDY:Uplift of the tropical Andes had a significant impact on the diversification of South American flora and fauna. Recent biogeographic inquiries have established patterns of Andean divergence, but investigations on ferns are scant. The fern genus Polystichum Roth (Dryopteridaceae) combines widespread...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300191
更新日期:2014-02-01 00:00:00
abstract:UNLABELLED:• PREMISE OF THE STUDY:The question why leaf dimensions vary so much between species has long puzzled ecologists. Presumably, variation arises from selective forces acting on leaf function but which selective forces and which leaf functions? This investigation assesses the consistency of divergence in plant...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400379
更新日期:2015-03-01 00:00:00
abstract::Atriplex prostrata Boucher, a facultative halophyte, exhibits significant reduction in height and biomass and in the width of the cortex and vascular tissue under saline conditions. Therefore, the goal of this investigation was to determine the effect of salinity on plant growth as well as on the patterns of lignifica...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-09-01 00:00:00
abstract::Although theory has demonstrated rather low levels of gene flow are sufficient to counteract opposing mutation, drift, and selection, widespread recognition of the evolutionary importance of gene flow has come slowly. The perceived role of gene flow as an evolutionary force has vacillated over the last century. In the...
journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1400024
更新日期:2014-05-01 00:00:00
abstract:PREMISE OF THE STUDY:Koelreuteria (Sapindaceae) has four extant deciduous tree species, disjunctly distributed in eastern Asia and the Fiji Islands. While K. paniculata is widely cultivated, the biogeographic origin and evolutionary history of Koelreuteria remain unclear. METHODS:Fruits, pollen, wood, and leaves of cl...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200415
更新日期:2013-02-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Taxonomic groups have often been recognized on the basis of geographic distinctions rather than accurately representing evolutionary relationships. This has been particularly true for temperate and tropical members from the same family. Polygonaceae exemplifies this problem, wherein th...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000022
更新日期:2010-08-01 00:00:00
abstract::Terrestrial plant leaves are complex structures of composite materials. Resistance to fracture is achieved by a number of mechanisms, which operate at the molecular, cell, tissue, and structural levels. Leaves of dicots have different venation patterns and cell wall volume fractions from those of grasses, and conseque...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.10.1531
更新日期:2006-10-01 00:00:00
abstract:PREMISE:Inbreeding depression is traditionally considered a major factor favoring outcrossing in hermaphrodites. Recent experiments have shown that environmental conditions can influence the magnitude of inbreeding depression, but their relevance in natural populations is unclear. To investigate this, we studied the cl...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1410
更新日期:2020-01-01 00:00:00
abstract::Gelatinous fibers (G-fibers) are the active component of tension wood. G-fibers are unlike traditional fiber cells in that they possess a thick, nonlignified gelatinous layer (G-layer) internal to the normal secondary cell wall layers. For the past several decades, the G-layer has generally been presumed to be compose...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.2007368
更新日期:2008-06-01 00:00:00
abstract::We investigated patterns of fruit and seed production on inflorescences of a population of Pancratium maritimum in northwest Spain over a 2-yr period. Initial findings showed that the earliest opening flowers on an inflorescence are more likely to set fruit and produce more seeds than later opening flowers and that th...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-04-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Microsatellite loci were developed to characterize genetic variation and population subdivision in Khaya senegalensis (Desr.) A. Juss. (Meliaceae). • METHODS AND RESULTS:Microsatellite loci were identified from genomic DNA sequences generated using the 454 GS-FLX titanium platform. Pr...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000300
更新日期:2010-11-01 00:00:00
abstract::We examined the function of floral traits associated with buzz pollination through studies of Rhexia virginica (Melastomataceae) in the Muskoka region of Ontario, Canada. Controlled pollinations demonstrated that the species is self-compatible, but dependent on insects for pollen transfer. Bumble bees made 82 and 90% ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-04-01 00:00:00
abstract::Correlations were examined between habitat characters and clonal structures determined by the RAPD (random amplified polymorphic DNA) assay in five populations of Oryza rufipogon in China. Nine of 175 decameric primers were used in the study because they reproducibly amplified polymorphisms. The extent of clonality to...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-06-01 00:00:00
abstract:PREMISE OF THE STUDY:Despite being highly fertile and occupying a large geographic region, the North American heartleaf bittercress (Cardamine cordifolia; Brassicaceae) has a puzzling triploid-like chromosome number (2n = 3x = 24). As most triploids are sterile, we embarked on a detailed analysis of the C. cordifolia g...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500452
更新日期:2016-07-01 00:00:00
abstract:PREMISE OF THE STUDY:A key question in evolutionary biology is why some clades are more successful by being widespread geographically, biome diverse, or species-rich. To extend understanding of how shifts in area, biomes, and pollinators impact diversification in plants, we examined the relationships of these shifts to...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1268
更新日期:2019-04-01 00:00:00
abstract::The micromorphology of pits in tracheary elements was examined in 35 species representing 29 genera of Rosaceae and related families to evaluate the assumption that angiosperm pits are largely invariant. In most Rosaceae, pit membranes between fibers and tracheids frequently appear to have amorphous thickenings with a...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.4.503
更新日期:2007-04-01 00:00:00
abstract::Clarkia (Onagraceae) is a genus of 42 annual species, mostly native to California, that has served as a model for many studies of plant evolutionary biology, particularly morphological, cytological, and genetic divergence; reproductive isolation; and speciation. Section Sympherica is the largest section with eight dip...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.2.284
更新日期:2003-02-01 00:00:00