Fossil Angiosperm Leaves: Paleobotany's Difficult Children Prove Themselves

The great bulk of the angiosperm fossil record consists of isolated fossil leaves that preserve abundant shape and venation (leaf architectural) information but are difficult to identify because they are not attached to other plant organs. Thus, poor taxonomic knowledge has tempered the tremendous potential of fossil leaves for constructing finely resolved records of biodiversity through time, extinction and recovery, past climate change and biotic response, paleoecology, and plant-animal associations. Moreover, paleoecological and paleoclimatic interpretations of fossil leaves are in great need of new approaches. Recent work is rapidly increasing the scientific value of fossil angiosperm leaves through advances in traditional paleobotanical reconstruction, phylogenetic understanding of both leaf architecture and the response of leaf shape to climate, quantitative plant ecology using measurable, correlatable leaf traits, and improved understanding of insect leaf-feeding damage. These emerging areas offer many novel opportunities to link paleoecology and neoecology. Increased collaboration across traditionally separate research areas is critical to continued success.

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Reconstructing paleoclimate and paleoecology using fossil leaves

10.31233/osf.io/stzuc ◽

2017 ◽

Cited By ~ 1

Author(s):

Daniel J. Peppe ◽

Aly Baumgartner ◽

Andrew G. Flynn ◽

Benjamin Blonder

Keyword(s):

Plant Traits ◽

Terrestrial Ecosystems ◽

Leaf Traits ◽

Leaf Life Span ◽

Computer Algorithms ◽

Leaf Trait ◽

Research Areas ◽

Fossil Leaves ◽

Leaf Economic Spectrum ◽

The Relationship

Plants are strongly influenced by their surrounding environment, which makes them reliable indicators of climate and ecology. The relationship between climate, ecology, plant traits and the geographic distribution of plants based on their climatic tolerances have been used to develop plant-based proxies for reconstructing paleoclimate and paleoecology. These proxies are some of the most accurate and precise methods for reconstructing the climate and ecology of ancient terrestrial ecosystems and have been applied from the Cretaceous to the Quaternary. Despite their utility, the relationships between plant traits and climate that underlie these methods are confounded by other factors such as leaf life-span and phylogenetic history. Work focused on better understanding these confounding factors, incorporating the influence of phylogeny and leaf economic spectrum traits into proxies, expanding modern leaf trait-climate and ecology calibration datasets to additional biogeographic areas and climate regimes, and developing automated computer algorithms for measuring leaf traits are important growing research areas that will help considerably improve plant-based paleoclimate and paleoecological proxies.

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Genes, cognition, and social behavior: Next steps for foundations and researchers

Politics and the Life Sciences ◽

10.2990/30_2_65 ◽

2011 ◽

Vol 30 (2) ◽

pp. 65-87 ◽

Cited By ~ 4

Author(s):

Arthur Lupia

Keyword(s):

Social Behavior ◽

Political Science ◽

National Science Foundation ◽

Scientific Practices ◽

Social Scientists ◽

Research Areas ◽

Unpublished Report ◽

Summary Statement ◽

The One ◽

Scientific Value

Editor's note This well circulated but heretofore unpublished report is the summary statement of an interdisciplinary meeting of scholars convened by the National Science Foundation in Arlington, Virginia on June 28, 2010. The workshop, which was funded by the NSF's Political Science Program (Social, Behavioral & Economic Sciences Grant #1037831), was convened to answer two compelling questions: Are studies of social behavior that build from discoveries about genes and/or cognition of greater social and scientific value than studies of the same topics that ignore such factors? And, how can fundable research on genes, cognition, and politics generate transformative scientific practices, infrastructure, and findings of high social value? Assembled for the workshop were a group of scholars representing diverse yet increasingly connected research areas, including genetics, cognitive science and neuroscience, decision making and risk analysis, economics, political science, and sociology. The resulting report outlines the substantial challenges facing interdisciplinary research but also describes the considerable contributions to knowledge that could result from sustained collaborations between biologists, geneticists, and brain scientists on the one hand and social scientists on the other. Following this main report are three white papers by Jeremy Freese. Elizabeth Hammock, and Rose McDermott, which address importmant considerations related to the discussion. For a download of the full report, see http://www.isr.umich.edu.cps/workshop.Welcome.html.

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Trait-based plant ecology a flawed tool in climate studies? The leaf traits of wild olive that pattern with climate are not those routinely measured

PLoS ONE ◽

10.1371/journal.pone.0219908 ◽

2019 ◽

Vol 14 (7) ◽

pp. e0219908

Author(s):

Jalal Kassout ◽

Jean-Frederic Terral ◽

John G. Hodgson ◽

Mohammed Ater

Keyword(s):

Leaf Traits ◽

Plant Ecology ◽

Wild Olive ◽

Climate Studies

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Multivariate genome-wide association study of leaf shape in a Populus deltoides and P. simonii F1 pedigree

PLoS ONE ◽

10.1371/journal.pone.0259278 ◽

2021 ◽

Vol 16 (10) ◽

pp. e0259278

Author(s):

Wenguo Yang ◽

Dan Yao ◽

Hainan Wu ◽

Wei Zhao ◽

Yuhua Chen ◽

...

Keyword(s):

Leaf Morphology ◽

Mixed Model ◽

Linear Mixed Model ◽

Populus Deltoides ◽

Leaf Shape ◽

Leaf Traits ◽

Leaf Length ◽

Moderate Number ◽

Genome Wide ◽

Poplar Leaf

Leaf morphology exhibits tremendous diversity between and within species, and is likely related to adaptation to environmental factors. Most poplar species are of great economic and ecological values and their leaf morphology can be a good predictor for wood productivity and environment adaptation. It is important to understand the genetic mechanism behind variation in leaf shape. Although some initial efforts have been made to identify quantitative trait loci (QTLs) for poplar leaf traits, more effort needs to be expended to unravel the polygenic architecture of the complex traits of leaf shape. Here, we performed a genome-wide association analysis (GWAS) of poplar leaf shape traits in a randomized complete block design with clones from F1 hybrids of Populus deltoides and Populus simonii. A total of 35 SNPs were identified as significantly associated with the multiple traits of a moderate number of regular polar radii between the leaf centroid and its edge points, which could represent the leaf shape, based on a multivariate linear mixed model. In contrast, the univariate linear mixed model was applied as single leaf traits for GWAS, leading to genomic inflation; thus, no significant SNPs were detected for leaf length, measures of leaf width, leaf area, or the ratio of leaf length to leaf width under genomic control. Investigation of the candidate genes showed that most flanking regions of the significant leaf shape-associated SNPs harbored genes that were related to leaf growth and development and to the regulation of leaf morphology. The combined use of the traditional experimental design and the multivariate linear mixed model could greatly improve the power in GWAS because the multiple trait data from a large number of individuals with replicates of clones were incorporated into the statistical model. The results of this study will enhance the understanding of the genetic mechanism of leaf shape variation in Populus. In addition, a moderate number of regular leaf polar radii can largely represent the leaf shape and can be used for GWAS of such a complicated trait in Populus, instead of the higher-dimensional regular radius data that were previously considered to well represent leaf shape.

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Geometric and topological approaches to shape variation in Ginkgo leaves

Royal Society Open Science ◽

10.1098/rsos.210978 ◽

2021 ◽

Vol 8 (11) ◽

Author(s):

Haibin Hang ◽

Martin Bauer ◽

Washington Mio ◽

Luke Mander

Keyword(s):

Leaf Shape ◽

Persistent Homology ◽

Leaf Size ◽

Geometric Method ◽

Topological Method ◽

Shape Variation ◽

Short Shoot ◽

Plant Trait ◽

Elastic Curves ◽

Fossil Leaves

Leaf shape is a key plant trait that varies enormously. The range of applications for data on this trait requires frequent methodological development so that researchers have an up-to-date toolkit with which to quantify leaf shape. We generated a dataset of 468 leaves produced by Ginkgo biloba , and 24 fossil leaves produced by evolutionary relatives of extant Ginkgo . We quantified the shape of each leaf by developing a geometric method based on elastic curves and a topological method based on persistent homology. Our geometric method indicates that shape variation in modern leaves is dominated by leaf size, furrow depth and the angle of the two lobes at the leaf base that is also related to leaf width. Our topological method indicates that shape variation in modern leaves is dominated by leaf size and furrow depth. We have applied both methods to modern and fossil material: the methods are complementary, identifying similar primary patterns of variation, but also revealing different aspects of morphological variation. Our topological approach distinguishes long-shoot leaves from short-shoot leaves, both methods indicate that leaf shape influences or is at least related to leaf area, and both could be applied in palaeoclimatic and evolutionary studies of leaf shape.

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Assessing the leaf shape dynamic through marker–trait association under drought stress in a rice germplasm panel

Plant Genetic Resources ◽

10.1017/s1479262121000587 ◽

2022 ◽

pp. 1-7

Author(s):

Mayuri D. Mahalle ◽

S. K. Chetia ◽

P. C. Dey ◽

R. N. Sarma ◽

A. R. Baruah ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Flag Leaf ◽

Leaf Shape ◽

Leaf Traits ◽

Northeast India ◽

Phenotypic Variance ◽

Trait Association ◽

Rice Germplasm ◽

Leaf Physiology

Abstract The flag leaf acts as a functional leaf in rice, Oryza sativa L., primarily supplying photosynthate to the developing grains and influencing yields to a certain extent. Drought stress damages the leaf physiology, severely affecting grain fertility. Autumn rice of northeast India is called locally as ‘ahu’ rice, and is known for its drought tolerance. Exploring diverse germplasm resources at the morphological level using an association mapping approach can aid in identifying the genomic regions influencing leaf shape dynamics. A marker–trait association (MTA) study was carried out using 95 polymorphic SSR markers and a panel of 273 ahu rice germplasm accessions in drought stress and irrigated conditions. The trials suggest that at the vegetative stage, drought stress significantly affects leaf morphology. The leaf physiology of some tolerant accessions was relatively little affected by stress and these can be considered as ideal varieties for drought conditions. The phenotypic coefficient of variance and genotypic coefficient of variance values implied moderate to high variability for the leaf traits studied. Analysis of molecular variance inferred that 11% of variation in the germplasm panel was due to differences between populations, while the remaining 89% may be attributed to a difference within subgroups formed through STRUCTURE analysis. Using the mixed linear model approach revealed 11 MTAs explaining between 4.5 and 20.0% of phenotypic variance at P > 0.001 for all the leaf traits. The study concludes that ahu rice germplasm is extremely diverse and can serve as a valuable resource for mining desirable alleles for drought tolerance.

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Lower Cretaceous conifers from Apple Bay, Vancouver Island: Picea-like leaves, Midoriphyllum piceoides gen. et sp. nov. (Pinaceae)This paper is one of a selction of papers published on the Special Issue on Systematics Research.

Botany ◽

10.1139/b08-061 ◽

2008 ◽

Vol 86 (7) ◽

pp. 649-657 ◽

Cited By ~ 12

Author(s):

Ruth A. Stockey ◽

Nicholas J.P. Wiebe

Keyword(s):

Cross Section ◽

Lower Cretaceous ◽

Leaf Shape ◽

Guard Cells ◽

Vancouver Island ◽

Vascular Bundles ◽

Special Issue ◽

Fossil Leaves ◽

Transfusion Tissue ◽

Resin Canals

A diverse assemblage of fossil conifer leaves was identified in calcareous marine concretions from the Lower Cretaceous (Valanginian–Hauterivian) Apple Bay locality, Vancouver Island. Of the hundreds of isolated leaf fragments, most show affinities to Pinaceae. Leaves with closest similarities to Picea (spruce) were studied using cellulose acetate peels. Picea-like leaves vary in cross-section from rhomboidal, pentagonal, triangular, to ovoid. One fused vascular bundle with a centrally located ray and abaxial sclerenchyma is surrounded by a circular endodermis and transfusion tissue. Mesophyll is plicate containing two lateral external resin canals surrounded by a sclerenchyma sheath. Hypodermal fibres are one to three layers thick, except in areas of stomata. Leaves are amphistomatic, with sunken guard cells. Vascular bundles are identical anatomically to Picea; however, plicate mesophyll is similar to that in leaves of Pinus. Extensive sclerenchyma in the hypodermis and surrounding resin canals differs from that in most extant Picea. The major difference between these leaves and those of Picea is leaf shape. These fossil leaves probably belong to an extinct pinaceous conifer, and are described as Midoriphyllum piceoides gen. et sp. nov. Similar evidence from Cretaceous seed cones suggests that like the angiosperms, the Pinaceae were undergoing rapid mosaic evolution during the Lower Cretaceous.

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Comparisons of stemflow and its bio-/abiotic influential factors between two xerophytic shrub species

Hydrology and Earth System Sciences ◽

10.5194/hess-21-1421-2017 ◽

2017 ◽

Vol 21 (3) ◽

pp. 1421-1438 ◽

Cited By ~ 10

Author(s):

Chuan Yuan ◽

Guangyao Gao ◽

Bojie Fu

Keyword(s):

Plant Traits ◽

Leaf Shape ◽

Precipitation Amount ◽

Great Influence ◽

Leaf Traits ◽

Influential Factors ◽

Leaf Biomass ◽

Shrub Species ◽

Allocation Pattern ◽

Plant Trait

Abstract. Stemflow transports nutrient-enriched precipitation to the rhizosphere and functions as an efficient terrestrial flux in water-stressed ecosystems. However, its ecological significance has generally been underestimated because it is relatively limited in amount, and the biotic mechanisms that affect it have not been thoroughly studied at the leaf scale. This study was conducted during the 2014 and 2015 rainy seasons at the northern Loess Plateau of China. We measured the branch stemflow volume (SFb), shrub stemflow equivalent water depth (SFd), stemflow percentage of incident precipitation (SF %), stemflow productivity (SFP), funnelling ratio (FR), the meteorological characteristics and the plant traits of branches and leaves of C. korshinskii and S. psammophila. This study evaluated stemflow efficiency for the first time with the combined results of SFP and FR, and sought to determine the inter- and intra-specific differences of stemflow yield and efficiency between the two species, as well as the specific bio-/abiotic mechanisms that affected stemflow. The results indicated that C. korshinskii had a greater stemflow yield and efficiency at all precipitation levels than that of S. psammophila. The largest inter-specific difference generally occurred at the 5–10 mm branches during rains of ≤  2 mm. Precipitation amount was the most influential meteorological characteristic that affected stemflow yield and efficiency in these two endemic shrub species. Branch angle was the most influential plant trait on FR. For SFb, stem biomass and leaf biomass were the most influential plant traits for C. korshinskii and S. psammophila, respectively. For SFP of these two shrub species, leaf traits (the individual leaf area) and branch traits (branch size and biomass allocation pattern) had a great influence during lighter rains  ≤  10 mm and heavier rains  >  15 mm, respectively. The lower precipitation threshold to start stemflow allowed C. korshinskii (0.9 mm vs. 2.1 mm for S. psammophila) to employ more rains to harvest water via stemflow. The beneficial leaf traits (e.g., leaf shape, arrangement, area, amount) might partly explain the greater stemflow production of C. korshinskii. Comparison of SFb between the foliated and manually defoliated shrubs during the 2015 rainy season indicated that the newly exposed branch surface at the defoliated period and the resulting rainfall intercepting effects might be an important mechanism affecting stemflow in the dormant season.

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Population structure of Erythronium dens-canis L. (Liliaceae) in the northern Apennines (Italy)

Italian Botanist ◽

10.3897/italianbotanist.4.12439 ◽

2017 ◽

Vol 4 ◽

pp. 1-14

Author(s):

Paolo Pupillo ◽

Giovanni Astuti

Keyword(s):

Functional Role ◽

Time Course ◽

Genetic Basis ◽

Leaf Shape ◽

Leaf Traits ◽

Juvenile Stage ◽

Pollinator Attraction ◽

Leaf Type ◽

The Mean

Relationships between age, time of emergence, and leaf traits of individuals were investigated in a population of Erythroniumdens-canis L. in a hilly woodland area named Farneto-C, near Bologna, Italy. In 2015, 591 individuals were counted, 19 of which were flowering (FLO), 442 were mature non-flowering (MNF) and 130 were juveniles (JUV). FLO emerged at the end of February, whereas most MNF and JUV appeared at the middle and end of March, respectively. The mean aboveground survivorship of MNF was 24 days. Most MNF had large, oval to shield-shaped leaves with red-brown mottling, whereas most JUV leaves were smaller, usually oblong or lanceolate with a rough maculation or none. These results suggest that both timing of emergence and leaf shape are related to the age of the bulb. Based on leaf background, plants were classified into three major types with a likely genetic basis in the 2015 and 2016 surveys (the latter limited to FLO): a dominant silvery type (SLV, 62–74%), silvery-and-green type (S&G, 23–32%), and a less frequent vivid-green type (GRN, 3–5%). Several subtypes were also identified, but only one was dominant within each type. The three basic patterns appear to be phenotypically stable and no differences between MNF and FLO were found; once the juvenile stage has passed, each plant produces the same leaf type year after year. In addition, our results on the discoloration time-course of red-brown spots suggest that the functional role of leaf mottling is not related to pollinator attraction. Instead, leaf mottling could play a role in camouflage against herbivores.The observed massive grazing on flowers, more than leaves, could explain why the frequency of mature individuals was biased towards the non-flowering ones.

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Biovera-Epi: A new database on species diversity, community composition, and leaf functional traits of vascular epiphytes along an elevational gradient in Mexico

10.3897/arphapreprints.e72184 ◽

2021 ◽

Author(s):

Valeria Guzmán-Jacob ◽

Patrick Weigelt ◽

Dylan Craven ◽

Gerhard Zotz ◽

Thorsten Krömer ◽

...

Keyword(s):

Community Composition ◽

Functional Traits ◽

Leaf Traits ◽

Elevational Gradient ◽

Plant Ecology ◽

Distribution Data ◽

Leaf Functional Traits ◽

Vascular Epiphytes ◽

Forest Use ◽

Study Sites

This data paper describes a new, comprehensive database (BIOVERA-Epi) on species distributions and leaf functional traits of vascular epiphytes, a poorly studied plant group, along gradients of elevation and forest-use intensity in the central part of Veracruz State, Mexico. The distribution data includes frequencies of 271 vascular epiphyte species belonging to 92 genera and 23 families across 120 20 m × 20 m forest plots at eight study sites along an elevational gradient from sea level to 3500 m a.s.l. In addition, BIOVERA-Epi provides information on 1595 measurements of nine morphological and chemical leaf traits from 474 individuals and 102 species. For morphological leaf traits, we provide data on each sampled leaf. For chemical leaf traits, we provide data at the species level per site and land-use type. We also provide complementary information for each of the sampled plots and host trees. BIOVERA-Epi contributes to an emerging body of synthetic epiphytes studies combining functional traits and community composition. BIOVERA-Epi includes data on species frequency and leaf traits from 120 forest plots distributed along an elevational gradient including six different forest types and three levels of forest-use intensity. It will expand the breadth of studies on epiphyte diversity, conservation, and functional plant ecology in the Neotropics and will contribute to future synthetic studies on the ecology and diversity of tropical epiphyte assemblages.

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