Augmented laminography, a correlative 3D imaging method for revealing the inner structure of compressed fossils

Zubér, M. S.; Laaß, Michael; Hamann, Elias; Kretschmer, Sophie; Hauschke, Norbert; Kamp, Thomas van de; Baumbach, Tilo; Koenig, Thomas

doi:10.1038/srep41413

Cited by 23 publications

(19 citation statements)

References 46 publications

(49 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In spite of this, improved imaging tools are allowing palaeontologists to extract more information from fossils. Arthropod compression fossils have for some years been productively investigated using polarized light and/or immersion in liquid [113], but have more recently provided additional data using such approaches as fluorescence microscopy [114], laminography [115] and computed micro-tomography [116]. These techniques may resolve some of the current controversies about homologies in fossil taxa that complicate character coding.…”

Section: Discussionmentioning

confidence: 99%

Developing an integrated understanding of the evolution of arthropod segmentation using fossils and evo-devo

Chipman

Edgecombe

2019

Proc. R. Soc. B.

View full text Add to dashboard Cite

Segmentation is fundamental to the arthropod body plan. Understanding the evolutionary steps by which arthropods became segmented is being transformed by the integration of data from evolutionary developmental biology (evo-devo), Cambrian fossils that allow the stepwise acquisition of segmental characters to be traced in the arthropod stem-group, and the incorporation of fossils into an increasingly well-supported phylogenetic framework for extant arthropods based on genomic-scale datasets. Both evo-devo and palaeontology make novel predictions about the evolution of segmentation that serve as testable hypotheses for the other, complementary data source. Fossils underpin such hypotheses as arthropodization originating in a frontal appendage and then being co-opted into other segments, and segmentation of the endodermal midgut in the arthropod stem-group. Insights from development, such as tagmatization being associated with different modes of segment generation in different body regions, and a distinct patterning of the anterior head segments, are complemented by palaeontological evidence for the pattern of tagmatization during ontogeny of exceptionally preserved fossils. Fossil and developmental data together provide evidence for a short head in stem-group arthropods and the mechanism of its formation and retention. Future breakthroughs are expected from identification of molecular signatures of developmental innovations within a phylogenetic framework, and from a focus on later developmental stages to identify the differentiation of repeated units of different systems within segmental precursors.

show abstract

Section: Discussionmentioning

confidence: 99%

Developing an integrated understanding of the evolution of arthropod segmentation using fossils and evo-devo

Chipman

Edgecombe

2019

Proc. R. Soc. B.

View full text Add to dashboard Cite

show abstract

“…Each measurement consists of a 360° rotation of the samples in the X-ray beam between the radiation source and detector with a projection of 0.176° each, resulting in 2048 projections over the entire measurement. The scanner is described in more detail elsewhere [ 69 , 70 ]. The image processing (noise filtering and segmentation) was performed with ImageJ2 over the distribution Fiji.…”

Section: Methodsmentioning

confidence: 99%

High Moisture Extrusion of Soy Protein: Investigations on the Formation of Anisotropic Product Structure

Wittek

Zeiler

Karbstein

et al. 2021

Foods

View full text Add to dashboard Cite

The high moisture extrusion of plant proteins is well suited for the production of protein-rich products that imitate meat in their structure and texture. The desired anisotropic product structure of these meat analogues is achieved by extrusion at high moisture content (>40%) and elevated temperatures (>100 °C); a cooling die prevents expansion of the matrix and facilitates the formation of the anisotropic structure. Although there are many studies focusing on this process, the mechanisms behind the structure formation still remain largely unknown. Ongoing discussions are based on two very different hypotheses: structure formation due to alignment and stabilization of proteins at the molecular level vs. structure formation due to morphology development in multiphase systems. The aim of this paper is, therefore, to investigate the mechanism responsible for the formation of anisotropic structures during the high moisture extrusion of plant proteins. A model protein, soy protein isolate, is extruded at high moisture content and the changes in protein–protein interactions and microstructure are investigated. Anisotropic structures are achieved under the given conditions and are influenced by the material temperature (between 124 and 135 °C). Extrusion processing has a negligible effect on protein–protein interactions, suggesting that an alignment of protein molecules is not required for the structure formation. Instead, the extrudates show a distinct multiphase system. This system consists of a water-rich, dispersed phase surrounded by a water-poor, i.e., protein-rich, continuous phase. These findings could be helpful in the future process and product design of novel plant-based meat analogues.

show abstract

“…Alternatively, technological advances may allow for 3D reconstruction from 2D sources. 3D images of specimens can be taken using computed tomography (CT) (Abel, Laurini & Richter, 2012) or augmented laminography (AL) (Zuber et al ., 2017). Subsequently, broken parts can be segmented and reconstructed according to techniques described by Lautenschlager (2016).…”

Section: Physical Approachesmentioning

confidence: 99%

The diet of early birds based on modern and fossil evidence and a new framework for its reconstruction

Miller

Pittman

2021

Biological Reviews

View full text Add to dashboard Cite

Birds are some of the most diverse organisms on Earth, with species inhabiting a wide variety of niches across every major biome. As such, birds are vital to our understanding of modern ecosystems. Unfortunately, our understanding of the evolutionary history of modern ecosystems is hampered by knowledge gaps in the origin of modern bird diversity and ecosystem ecology. A crucial part of addressing these shortcomings is improving our understanding of the earliest birds, the non-avian avialans (i.e. non-crown birds), particularly of their diet. The diet of non-avian avialans has been a matter of debate, in large part because of the ambiguous qualitative approaches that have been used to reconstruct it. Here we review methods for determining diet in modern and fossil avians (i.e. crown birds) as well as non-avian theropods, and comment on their usefulness when applied to non-avian avialans. We use this to propose a set of comparable, quantitative approaches to ascertain fossil bird diet and on this basis provide a consensus of what we currently know about fossil bird diet. While no single approach can precisely predict diet in birds, each can exclude some diets and narrow the dietary possibilities. We recommend combining (i) dental microwear, (ii) landmark-based muscular reconstruction, (iii) stable isotope geochemistry, (iv) body mass estimations, (v) traditional and/or geometric morphometric analysis, (vi) lever modelling, and (vii) finite element analysis to reconstruct fossil bird diet accurately. Our review provides specific methodologies to implement each approach and discusses complications future researchers should keep in mind. We note that current forms of assessment of dental mesowear, skull traditional morphometrics, geometric morphometrics, and certain stable isotope systems have yet to be proven effective at discerning fossil bird diet. On this basis we report the current state of knowledge of non-avian avialan diet which remains very incomplete. The ancestral dietary condition in non-avian avialans remains unclear due to scarce data and contradictory evidence in Archaeopteryx. Among early non-avian pygostylians, Confuciusornis has finite element analysis and mechanical advantage evidence pointing to herbivory, whilst Sapeornis only has mechanical advantage evidence indicating granivory, agreeing with fossilised ingested material known for this taxon. The enantiornithine ornithothoracine Shenqiornis has mechanical advantage and pedal morphometric evidence pointing to carnivory. In the hongshanornithid ornithuromorph Hongshanornis only mechanical advantage evidence indicates granivory, but this agrees with evidence of gastrolith ingestion in this taxon. Mechanical advantage and ingested fish support carnivory in the songlingornithid ornithuromorph Yanornis. Due to the sparsity of robust dietary assignments, no clear trends in non-avian avialan dietary evolution have yet emerged. Dietary diversity seems to increase through time, but this is a preservational bias associated with a predominance of data fro...

show abstract

Augmented laminography, a correlative 3D imaging method for revealing the inner structure of compressed fossils

Cited by 23 publications

References 46 publications

Developing an integrated understanding of the evolution of arthropod segmentation using fossils and evo-devo

Developing an integrated understanding of the evolution of arthropod segmentation using fossils and evo-devo

High Moisture Extrusion of Soy Protein: Investigations on the Formation of Anisotropic Product Structure

The diet of early birds based on modern and fossil evidence and a new framework for its reconstruction

Contact Info

Product

Resources

About