scholarly journals How (much) do flowers vary? Unbalanced disparity among flower functional modules and a mosaic pattern of morphospace occupation in the order Ericales

2017 ◽  
Vol 284 (1852) ◽  
pp. 20170066 ◽  
Author(s):  
Marion Chartier ◽  
Stefan Löfstrand ◽  
Maria von Balthazar ◽  
Sylvain Gerber ◽  
Florian Jabbour ◽  
...  
Keyword(s):  
Morphological Diversity ◽  
Floral Traits ◽  
Functional Modules ◽  
Functional Constraints ◽  
Mosaic Pattern ◽  
Quantitative Distribution ◽  
Relative Contribution ◽  
Extant Species ◽  
Functional Patterns ◽  
Quantitative Analyses

The staggering diversity of angiosperms and their flowers has fascinated scientists for centuries. However, the quantitative distribution of floral morphological diversity (disparity) among lineages and the relative contribution of functional modules (perianth, androecium and gynoecium) to total floral disparity have rarely been addressed. Focusing on a major angiosperm order (Ericales), we compiled a dataset of 37 floral traits scored for 381 extant species and nine fossils. We conducted morphospace analyses to explore phylogenetic, temporal and functional patterns of disparity. We found that the floral morphospace is organized as a continuous cloud in which most clades occupy distinct regions in a mosaic pattern, that disparity increases with clade size rather than age, and that fossils fall in a narrow portion of the space. Surprisingly, our study also revealed that among functional modules, it is the androecium that contributes most to total floral disparity in Ericales. We discuss our findings in the light of clade history, selective regimes as well as developmental and functional constraints acting on the evolution of the flower and thereby demonstrate that quantitative analyses such as the ones used here are a powerful tool to gain novel insights into the evolution and diversity of flowers.

scholarly journals Changes in the Morphological Diversity of Larvae of Lance Lacewings, Mantis Lacewings and Their Closer Relatives over 100 Million Years

Insects ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 860
Author(s):  
Joachim T. Haug ◽  
Gideon T. Haug ◽  
Ana Zippel ◽  
Serita van der van der Wal ◽  
Patrick Müller ◽  
...  
Keyword(s):  
Shape Analysis ◽  
Morphological Diversity ◽  
Head Capsule ◽  
High Availability ◽  
Body Region ◽  
Ecological Diversity ◽  
The Past ◽  
Drastic Increase ◽  
Quantitative Analyses ◽  
Ecological Importance

Neuroptera, the group of lacewings, comprises only about 6000 species in the modern fauna, but is generally assumed to have been more diverse and important in the past. A major factor of the modern-day ecological diversity of the group, and supposedly in the past as well, is represented by the highly specialised larval forms of lacewings. Quantitative analyses of the morphology of larvae revealed a loss of morphological diversity in several lineages. Here we explored the diversity of the larvae of mantis lacewings (Mantispidae), lance lacewings (Osmylidae), beaded lacewings (Berothidae and Rhachiberothidae, the latter potentially an ingroup of Berothidae), and pleasing lacewings (Dilaridae), as well as fossil larvae, preserved in amber, resembling these. We used shape analysis of the head capsule and stylets (pair of conjoined jaws) as a basis due to the high availability of this body region in extant and fossil specimens and the ecological importance of this region. The analysis revealed a rather constant morphological diversity in Berothidae. Mantispidae appears to have lost certain forms of larvae, but has seen a drastic increase of larval diversity after the Cretaceous; this is in contrast to a significant decrease in diversity in adult forms.

Genetic differentiation within the Paralia longispina (Bacillariophyta) species complex

Botany ◽  
2012 ◽  
Vol 90 (3) ◽  
pp. 205-222 ◽  
Author(s):  
Michael L. MacGillivary ◽  
Irena Kaczmarska
Keyword(s):  
Large Subunit ◽  
Morphological Diversity ◽  
Its Region ◽  
Small Subunit ◽  
18S Rrna Gene ◽  
Tropical Species ◽  
Rrna Gene ◽  
Rbcl Gene ◽  
Extant Species ◽  
Practical Implications

We report on undiscovered genetic and morphological diversity within a diatom taxon known as Paralia longispina and propose three new, extant species of Paralia — Paralia allisonii sp. nov., Paralia crawfordii sp. nov., and Paralia ehrmanii sp. nov. — obtained from subtropical and tropical coasts of the Atlantic and Pacific oceans. Comprehensive examination and hierarchical clustering of frustule characters separated these three species from each other and from P. longispina. Each species possessed one or two unique morphological diagnostic characters. The internal transcribed spacer (ITS) region and a fragment of the small subunit (18S rRNA gene) of nuclear encoded rRNA and a portion of the 5′ end of the large subunit of the ribulose bisophosphate carboxylase (rbcL) gene of the chloroplast genome were related to the morphological groupings of monoclonal isolates of P. allisonii and P. crawfordii. The ITS2 secondary structure of the cultured clones of these two species had four helices. They differed by five hemicompensatory base changes (HCBCs) and substantial changes to the distal end of helix I, the region between helix II and helix III, and nearly all of helix IV. Our results better our understanding of the distribution of subtropical and tropical species of Paralia and have practical implications for the conservation of native microbial florae and for the possibility of ship ballast in human-mediated dispersal of these diatoms.

scholarly journals Comparative anatomy and phylogeny of the Forcipulatacea (Echinodermata: Asteroidea): insights from ossicle morphology

2019 ◽  
Vol 189 (3) ◽  
pp. 921-952 ◽  
Author(s):  
Marine Fau ◽  
Loïc Villier
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Analysis ◽  
Comparative Anatomy ◽  
Morphological Diversity ◽  
Consensus Tree ◽  
Sea Stars ◽  
Extant Species ◽  
Tree Resolution ◽  
Scanning Electron

Abstract A new phylogenetic analysis of the superorder Forcipulatacea is presented. Forcipulatacea is one of the three major groups of sea stars (Asteroidea: Echinodermata), composed of 400 extant species. The sampled taxa are thought to represent the morphological diversity of the group. Twenty-nine forcipulate taxa were sampled belonging to Asteriidae, Stichasteridae, Heliasteridae, Pedicellasteridae, Zoroasteridae and Brisingida. Specimens were dissected with bleach. Detailed description of the skeleton and the anatomy of the ossicles were investigated using scanning electron microscopy. Comparative anatomy allowed the scoring of 115 phylogenetically informative characters. The consensus tree resulting from the analysis recovers Asteriidae, Stichasteridae, Zoroasteridae and Brisingida as monophyletic. All types of morphological features contribute to tree resolution and may be appropriate for taxon diagnosis. The synapomorphies supporting different clades are described and discussed. Brisingida and Zoroasteridae are the best-supported clades. The potentially challenging position of Brisingida in the tree may be explained by homoplastic changes, but also by the presence of numerous non-applicable characters.

Form and function: structural analysis in evolutionary morphology

Paleobiology ◽  
1981 ◽  
Vol 7 (4) ◽  
pp. 430-442 ◽  
Author(s):  
George V. Lauder
Keyword(s):  
Structural Complexity ◽  
Morphological Diversity ◽  
Structural Features ◽  
Constrained Systems ◽  
Hierarchical Organization ◽  
Evolutionary Morphology ◽  
Form And Function ◽  
Historical Factors ◽  
Functional Patterns ◽  
And Function

A theoretical approach to the analysis of historical factors (Raup 1972) in evolutionary morphology is presented which addresses transformational hypotheses about structural systems. This (structural) approach to testing historical hypotheses about phylogenetic constraints on form and function and structural and functional versatility involves (1) the reconstruction of nested sets of structural features in monophyletic taxa, (2) the use of general or emergent organizational properties of structural and functional systems (as opposed to uniquely derived morphological features), and (3) the comparative examination of the consequences for structural and functional diversity of these general features in related monophyletic taxa.Three examples of emergent organizational properties are considered: structural complexity, repetition of parts, and the decoupling of primitively constrained systems. Two classes of hypotheses about the evolution of design are proposed. Transformational hypotheses concern historical pathways of change in form as a consequence of general organizational features which are primitive for a lineage. Relational hypotheses involve correlations between structure-function networks primitive for a clade and morphological diversity both between and within terminal taxa. To the extent that transformational and relational hypotheses about form are corroborated, they provide evidence of underlying regularity in the transformation of organic design that may be a consequence of the hierarchical organization of structural and functional patterns in organisms.

scholarly journals Accelerated body size evolution during cold climatic periods in the Cenozoic

2017 ◽  
Vol 114 (16) ◽  
pp. 4183-4188 ◽  
Author(s):  
Julien Clavel ◽  
Hélène Morlon
Keyword(s):  
Body Size ◽  
Biotic Interactions ◽  
Morphological Diversity ◽  
Evolutionary Rates ◽  
Phenotypic Evolution ◽  
Geological Time ◽  
Radiation Theory ◽  
Extant Species ◽  
Size Evolution ◽  
Body Size Evolution

How ecological and morphological diversity accumulates over geological time is much debated. Adaptive radiation theory has been successful in testing the effects of biotic interactions on the rapid divergence of phenotypes within a clade, but this theory ignores abiotic effects. The role of abiotic drivers on the tempo of phenotypic evolution has been tested only in a few lineages or small clades from the fossil record. Here, we develop a phylogenetic comparative framework for testing if and how clade-wide rates of phenotypic evolution vary with abiotic drivers. We apply this approach to comprehensive bird and mammal phylogenies, body size data for 9,465 extant species, and global average temperature trends over the Cenozoic. Across birds and mammals, we find that the rate of body size evolution is primarily driven by past climate. Unexpectedly, evolutionary rates are inferred to be higher during periods of cold rather than warm climates in most groups, suggesting that temperature influences evolutionary rates by modifying selective pressures rather than through its effect on energy availability and metabolism. The effect of climate on the rate of body size evolution seems to be a general feature of endotherm evolution, regardless of wide differences in species’ ecology and evolutionary history. These results suggest that climatic changes played a major role in shaping species’ evolution in the past and could also play a major role in shaping their evolution in the future.

scholarly journals Morphologic diversity of cutaneous sensory afferents revealed by genetically directed sparse labeling

eLife ◽  
2012 ◽  
Vol 1 ◽  
Author(s):  
Hao Wu ◽  
John Williams ◽  
Jeremy Nathans
Keyword(s):  
Sensory Neurons ◽  
Morphological Diversity ◽  
Hair Follicles ◽  
Field Size ◽  
Sensory Afferents ◽  
Specific Alkaline Phosphatase ◽  
Developmental Mechanisms ◽  
Sparse Labeling ◽  
Quantitative Analyses ◽  
Size And Structure

The diversity of cutaneous sensory afferents has been studied by many investigators using behavioral, physiologic, molecular, and genetic approaches. Largely missing, thus far, is an analysis of the complete morphologies of individual afferent arbors. Here we present a survey of cutaneous sensory arbor morphologies in hairy skin of the mouse using genetically-directed sparse labeling with a sensory neuron-specific alkaline phosphatase reporter. Quantitative analyses of 719 arbors, among which 77 were fully reconstructed, reveal 10 morphologically distinct types. Among the two types with the largest arbors, one contacts ∼200 hair follicles with circumferential endings and a second is characterized by a densely ramifying arbor with one to several thousand branches and a total axon length between one-half and one meter. These observations constrain models of receptive field size and structure among cutaneous sensory neurons, and they raise intriguing questions regarding the cellular and developmental mechanisms responsible for this morphological diversity.

Assessment of morphological diversity in acid lime (Citrus aurantifolia) genotypes based on floral traits in Jammu region

2021 ◽  
Vol 9 (2) ◽  
pp. 31-35
Author(s):  
Shilpy Kumari ◽  
Akash Sharma ◽  
Parshant Bakshi ◽  
Romesh Salgotra ◽  
Manish Sharma ◽  
...  
Keyword(s):  
Morphological Diversity ◽  
Floral Traits ◽  
Citrus Aurantifolia ◽  
Acid Lime

LANGUAGE DYNAMICS IN STRUCTURED FORM AND MEANING SPACES

2012 ◽  
Vol 15 (03n04) ◽  
pp. 1150021 ◽  
Author(s):  
BART DE BOER ◽  
TESSA VERHOEF
Keyword(s):  
Complex Form ◽  
Combinatorial Structure ◽  
Human Language ◽  
Functional Constraints ◽  
Cognitive Constraints ◽  
Learning Experiment ◽  
Fundamental Properties ◽  
Previous Generation ◽  
Relative Contribution ◽  
Iterated Learning

This paper reviews how the structure of form and meaning spaces influences the nature and the dynamics of the form-meaning mappings in language. In general, in a structured form or meaning space, not all forms and meanings are equivalent: some forms and some meanings are more easily confused with each other than with other forms or meanings. We first give a formalization of this idea, and explore how it influences robust form-meaning mappings. It is shown that some fundamental properties of human language, such as discreteness and combinatorial structure as well as universals of sound systems of human languages follow from optimal communication in structured form and meaning spaces. We also argue that some properties of human language follow less from these fundamental issues, and more from cognitive constraints. We then show that it is possible to experimentally investigate the relative contribution of functional constraints and of cognitive constraints. We illustrate this with an example of one of our own experiments, in which experimental participants have to learn a set of complex form-meaning mappings that have been produced by a previous generation of participants. Theoretically predicted properties appear in the sets of signals that emerge in this iterated learning experiment.

scholarly journals Using a biologically mimicking climbing robot to explore the performance landscape of climbing in lizards

2021 ◽  
Vol 288 (1947) ◽  
Author(s):  
Johanna T. Schultz ◽  
Hendrik K. Beck ◽  
Tina Haagensen ◽  
Tasmin Proost ◽  
Christofer J. Clemente
Keyword(s):  
Functional Constraints ◽  
Climbing Robot ◽  
Cost Of Transport ◽  
Performance Tasks ◽  
Natural Systems ◽  
High Speeds ◽  
Extant Species ◽  
Climbing Ability ◽  
The Cost ◽  
Relative Weighting

Locomotion is a key aspect associated with ecologically relevant tasks for many organisms, therefore, survival often depends on their ability to perform well at these tasks. Despite this significance, we have little idea how different performance tasks are weighted when increased performance in one task comes at the cost of decreased performance in another. Additionally, the ability for natural systems to become optimized to perform a specific task can be limited by structural, historic or functional constraints. Climbing lizards provide a good example of these constraints as climbing ability likely requires the optimization of tasks which may conflict with one another such as increasing speed, avoiding falls and reducing the cost of transport (COT). Understanding how modifications to the lizard bauplan can influence these tasks may allow us to understand the relative weighting of different performance objectives among species. Here, we reconstruct multiple performance landscapes of climbing locomotion using a 10 d.f. robot based upon the lizard bauplan, including an actuated spine, shoulders and feet, the latter which interlock with the surface via claws. This design allows us to independently vary speed, foot angles and range of motion (ROM), while simultaneously collecting data on climbed distance, stability and efficiency. We first demonstrate a trade-off between speed and stability, with high speeds resulting in decreased stability and low speeds an increased COT. By varying foot orientation of fore- and hindfeet independently, we found geckos converge on a narrow optimum of foot angles (fore 20°, hind 100°) for both speed and stability, but avoid a secondary wider optimum (fore −20°, hind −50°) highlighting a possible constraint. Modifying the spine and limb ROM revealed a gradient in performance. Evolutionary modifications in movement among extant species over time appear to follow this gradient towards areas which promote speed and efficiency.

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