scholarly journals Earwig fan designing: Biomimetic and evolutionary biology applications

2020 ◽  
Vol 117 (30) ◽  
pp. 17622-17626 ◽  
Author(s):  
Kazuya Saito ◽  
Ricardo Pérez-de la Fuente ◽  
Kôichi Arimoto ◽  
Young ah Seong ◽  
Hitoshi Aonuma ◽  
...  

Technologies to fold structures into compact shapes are required in multiple engineering applications. Earwigs (Dermaptera) fold their fanlike hind wings in a unique, highly sophisticated manner, granting them the most compact wing storage among all insects. The structural and material composition, in-flight reinforcement mechanisms, and bistable property of earwig wings have been previously studied. However, the geometrical rules required to reproduce their complex crease patterns have remained uncertain. Here we show the method to design an earwig-inspired fan by considering the flat foldability in the origami model, as informed by X-ray microcomputed tomography imaging. As our dedicated designing software shows, the earwig fan can be customized into artificial deployable structures of different sizes and configurations for use in architecture, aerospace, mechanical engineering, and daily use items. Moreover, the proposed method is able to reconstruct the wing-folding mechanism of an ancient earwig relative, the 280-million-year-oldProtelytron permianum. This allows us to propose evolutionary patterns that explain how extant earwigs acquired their wing-folding mechanism and to project hypothetical, extinct transitional forms. Our findings can be used as the basic design guidelines in biomimetic research for harnessing the excellent engineering properties of earwig wings, and demonstrate how a geometrical designing method can reveal morphofunctional evolutionary constraints and predict plausible biological disparity in deep time.

Studies of animal behavior often assume that all members of a species exhibit the same behavior. Geographic Variation in Behavior shows that, on the contrary, there is substantional variation within species across a wide range of taxa. Including work from pioneers in the field, this volume provides a balanced overview of research on behavioral characteristics that vary geographically. The authors explore the mechanisms by which behavioral differences evolve and examine related methodological issues. Taken together, the work collected here demonstrates that genetically based geographic variation may be far more widespread than previously suspected. The book also shows how variation in behavior can illuminate both behavioral evolution and general evolutionary patterns. Unique among books on behavior in its emphasis on geographic variation, this volume is a valuable new resource for students and researchers in animal behavior and evolutionary biology.


2018 ◽  
Author(s):  
Russell A. Ligon ◽  
Christopher D. Diaz ◽  
Janelle L. Morano ◽  
Jolyon Troscianko ◽  
Martin Stevens ◽  
...  

Ornaments used in courtship often vary wildly among species, reflecting the evolutionary interplay between mate preference functions and the constraints imposed by natural selection. Consequently, understanding the evolutionary dynamics responsible for ornament diversification has been a longstanding challenge in evolutionary biology. However, comparing radically different ornaments across species, as well as different classes of ornaments within species, is a profound challenge to understanding diversification of sexual signals. Using novel methods and a unique natural history dataset, we explore evolutionary patterns of ornament evolution in a group - the birds-of-paradise - exhibiting dramatic phenotypic diversification widely assumed to be driven by sexual selection. Rather than the tradeoff between ornament types originally envisioned by Darwin and Wallace, we found positive correlations among cross-modal (visual/acoustic) signals indicating functional integration of ornamental traits into a composite unit - the courtship phenotype. Furthermore, given the broad theoretical and empirical support for the idea that systemic robustness - functional overlap and interdependency - promotes evolutionary innovation, we posit that birds-of-paradise have radiated extensively through ornamental phenotype space as a consequence of the robustness in the courtship phenotype that we document at a phylogenetic scale. We suggest that the degree of robustness in courtship phenotypes among taxa can provide new insights into the relative influence of sexual and natural selection on phenotypic radiations.Author SummaryAnimals frequently vary widely in ornamentation, even among closely related species. Understanding the patterns that underlie this variation is a significant challenge, requiring comparisons among drastically different traits - like comparing apples to oranges. Here, we use novel analytical approaches to quantify variation in ornamental diversity and richness across the wildly divergent birds-of-paradise, a textbook example of how sexual selection can profoundly shape organismal phenotypes. We find that color and acoustic complexity, along with behavior and acoustic complexity, are positively correlated across evolutionary time-scales. Positive covariation among ornament classes suggests that selection is acting on correlated suites of traits - a composite courtship phenotype - and that this integration may be partially responsible for the extreme variation we see in birds-of-paradise.


2021 ◽  
Vol 13 (16) ◽  
pp. 9269
Author(s):  
Saddam Hussein Abo Sabah ◽  
Luis Hii Anneza ◽  
Mohd Irwan Juki ◽  
Hisham Alabduljabbar ◽  
Norzila Othman ◽  
...  

This study investigated the optimization of the bioconcrete engineering properties and durability as a response of the calcium lactate (CL) content (0.22–2.18 g/L) and curing duration (7–28 days) using the response surface methodology (RSM). Scanning electronic microscopy (SEM) was conducted to evaluate the microstructure of calcium precipitated inside the bioconcrete. The results indicated that the optimal conditions for the engineering properties of concrete and durability were determined at 2.18 g/L of CL content after 23.4 days. The actual and predicted values of the compressive strength, splitting tensile strength, flexural strength, and water absorption were 43.51 vs. 43.43, 3.19 vs. 3.19, 6.93 vs. 5.50, and 7.55 vs. 7.55, respectively, with a level of confidence exceeding 95%. The scanning electron microscope (SEM) images and energy-dispersive X-ray spectroscopy (EDX) proved that the amount of calcium increased with the increase in CL content up to 2.81 g/L at 23.4 days, reducing the pores inside the concrete and making it a great potential option for healing of concrete structures.


Diversity ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 164 ◽  
Author(s):  
Peter Houde ◽  
Edward L. Braun ◽  
Lawrence Zhou

Assessing the applicability of theory to major adaptive radiations in deep time represents an extremely difficult problem in evolutionary biology. Neoaves, which includes 95% of living birds, is believed to have undergone a period of rapid diversification roughly coincident with the Cretaceous–Paleogene (K-Pg) boundary. We investigate whether basal neoavian lineages experienced an ecological release in response to ecological opportunity, as evidenced by density compensation. We estimated effective population sizes (Ne) of basal neoavian lineages by combining coalescent branch lengths (CBLs) and the numbers of generations between successive divergences. We used a modified version of Accurate Species TRee Algorithm (ASTRAL) to estimate CBLs directly from insertion–deletion (indel) data, as well as from gene trees using DNA sequence and/or indel data. We found that some divergences near the K-Pg boundary involved unexpectedly high gene tree discordance relative to the estimated number of generations between speciation events. The simplest explanation for this result is an increase in Ne, despite the caveats discussed herein. It appears that at least some early neoavian lineages, similar to the ancestor of the clade comprising doves, mesites, and sandgrouse, experienced ecological release near the time of the K-Pg mass extinction.


2019 ◽  
Vol 36 (8) ◽  
pp. 1686-1700 ◽  
Author(s):  
Covadonga Vara ◽  
Laia Capilla ◽  
Luca Ferretti ◽  
Alice Ledda ◽  
Rosa A Sánchez-Guillén ◽  
...  

Abstract One of the major challenges in evolutionary biology is the identification of the genetic basis of postzygotic reproductive isolation. Given its pivotal role in this process, here we explore the drivers that may account for the evolutionary dynamics of the PRDM9 gene between continental and island systems of chromosomal variation in house mice. Using a data set of nearly 400 wild-caught mice of Robertsonian systems, we identify the extent of PRDM9 diversity in natural house mouse populations, determine the phylogeography of PRDM9 at a local and global scale based on a new measure of pairwise genetic divergence, and analyze selective constraints. We find 57 newly described PRDM9 variants, this diversity being especially high on Madeira Island, a result that is contrary to the expectations of reduced variation for island populations. Our analysis suggest that the PRDM9 allelic variability observed in Madeira mice might be influenced by the presence of distinct chromosomal fusions resulting from a complex pattern of introgression or multiple colonization events onto the island. Importantly, we detect a significant reduction in the proportion of PRDM9 heterozygotes in Robertsonian mice, which showed a high degree of similarity in the amino acids responsible for protein–DNA binding. Our results suggest that despite the rapid evolution of PRDM9 and the variability detected in natural populations, functional constraints could facilitate the accumulation of allelic combinations that maintain recombination hotspot symmetry. We anticipate that our study will provide the basis for examining the role of different PRDM9 genetic backgrounds in reproductive isolation in natural populations.


Plants ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 358
Author(s):  
Joan Pedrola-Monfort ◽  
David Lázaro-Gimeno ◽  
Carlos G. Boluda ◽  
Laia Pedrola ◽  
Alfonso Garmendia ◽  
...  

Among the most intriguing mysteries in the evolutionary biology of photosynthetic organisms are the genesis and consequences of the dramatic increase in the mitochondrial and nuclear genome sizes, together with the concomitant evolution of the three genetic compartments, particularly during the transition from water to land. To clarify the evolutionary trends in the mitochondrial genome of Archaeplastida, we analyzed the sequences from 37 complete genomes. Therefore, we utilized mitochondrial, plastidial and nuclear ribosomal DNA molecular markers on 100 species of Streptophyta for each subunit. Hierarchical models of sequence evolution were fitted to test the heterogeneity in the base composition. The best resulting phylogenies were used for reconstructing the ancestral Guanine-Cytosine (GC) content and equilibrium GC frequency (GC*) using non-homogeneous and non-stationary models fitted with a maximum likelihood approach. The mitochondrial genome length was strongly related to repetitive sequences across Archaeplastida evolution; however, the length seemed not to be linked to the other studied variables, as different lineages showed diverse evolutionary patterns. In contrast, Streptophyta exhibited a powerful positive relationship between the GC content, non-coding DNA, and repetitive sequences, while the evolution of Chlorophyta reflected a strong positive linear relationship between the genome length and the number of genes.


2014 ◽  
Vol 587-589 ◽  
pp. 1328-1331
Author(s):  
Achmad Fauzi ◽  
Zuraidah Djauhari ◽  
Usama Juniansyah Fauzi

In general, clayey soil was used as material embankment for increasing road way level before road structure being constructed. Some types of clay are expansive soil, its have been contributing to pavement failures and subsequently causing increased annual maintenance expenditure of the road. The pavements design/redesign methods are found to be the primary cause of these failures. Thus, it is quite important to propose the Kuantan clay engineering properties chart for design criteria that can improve the embankment performance. Thus, it is quite important to investigate the Kuantan clay properties so that can improve the embankment performance. This paper was evaluated and utilized of the engineering properties of Kuantan Clayey as material embankment for roadway. The research were conducted soil engineering properties, standard compaction, four days soaked California Bearing Ratio (CBR) test to ten clayey samples from various sites in Kuantan. The 4 days soaked CBR of clayey samples were prepared at optimum water content. The chemical element was investigated by Integrated Electron Microscope and Energy-Dispersive X-Ray Spectroscopy (SEM-EDS) and linear regression analysis were used to anlyzing relation among engineering properties variables.


1993 ◽  
Vol 125 (2) ◽  
pp. 181-258 ◽  
Author(s):  
Jarmila Kukalová-Peck ◽  
John F. Lawrence

AbstractA survey is made of the major features of the venation, articulation, and folding in the hind wings of Coleoptera. The documentation is based upon examination of 108 Coleoptera families and 200 specimens, and shown in 101 published figures. Wing veins and articular sclerites are homologized with elements of the neopteran wing groundplan, resulting in wing vein terminology that differs substantially from that generally used by coleopterists. We tabulate the differences between currently used venational nomenclature and the all-pterygote homologous symbols. The use of the neopteran groundplan, combined with the knowledge of the way in which veins evolved, provides many strong characters linked to the early evolutionary radiation of Coleoptera. The order originated with the development of the apical folding of the hind wings under the elytra executed by the radial and medial loop. The loops, which are very complex venational structures, further diversified in four distinctly different ways which mark the highest (suborder) taxa. The remaining venation and the wing articulation have changed with the loops, which formed additional synapomorphies and autapomorphies at the suborder, superfamily, and sometimes even family and tribe levels. Relationships among the four currently recognized suborders of Coleoptera are reexamined using hind wing characters. The number of wing-related apomorphies are 16 in Coleoptera, seven in Archostemata + Adephaga–Myxophaga, four in Adephaga–Myxophaga, seven in Myxophaga, nine in Archostemata, and five in Polyphaga. The following phylogenetic scheme is suggested: Polyphaga [Archostemata (Adephaga + Myxophaga)]. Venational evidence is given to define two major lineages (the hydrophiloid and the eucinetoid) within the suborder Polyphaga. The unique apical wing folding mechanism of beetles is described. Derived types of wing folding are discussed, based mainly on a survey of recent literature. A sister group relationship between Coleoptera and Strepsiptera is supported by hind wing evidence.


2009 ◽  
Vol 2009 ◽  
pp. 1-6 ◽  
Author(s):  
Tevye Kuykendall ◽  
Shaul Aloni ◽  
Ilan Jen-La Plante ◽  
Taleb Mokari

We demonstrated a method to control the bandgap energy of GaN nanowires by forming GaN@InGaN core-shell hybrid structures using metal organic chemical vapor deposition (MOCVD). Furthermore, we show the growth of Au nanoparticles on the surface of GaN nanowires in solution at room temperature. The work shown here is a first step toward engineering properties that are crucial for the rational design and synthesis of a new class of photocatalytic materials. The hybrid structures were characterized by various techniques, including photoluminescence (PL), energy dispersive x-ray spectroscopy (EDS), transmission and scanning electron microscopy (TEM and SEM), and x-ray diffraction (XRD).


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