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Sie werden, meine Damen und Herren, diese Bilder "2001 – A Space Odyssey" von Stanley Kubrick erinnern. Dieser Film, 1968 gedreht, also noch vor der ersten bemannten Mondlandung und noch vor dem takeoff des Computerzeitalters – dieser Film ist nicht nur eine Inkunabel eines ganzen Filmgenres, sondern er hat unsere Bilder von Weltraum und Computer maßgeblich geprägt. Er vermochte dies auch deswegen, weil Kubrick hier technische Phantasien und religiöse Motive, psychodelische Zeitreisen und metaphysische Sinnsuche, Urgeschichte und Endgeschichte, Angst vor der Technik und Sehnsüchte nach einer Entgrenzung jenseits von Zeit und Raum in maßstabsetzende Bilder brachte, verbunden mit einem niemals zuvor derart ungeheuren Einsatz von Musik und einer so noch niemals zuvor gesehenen Herabsetzung des Mediums, das seit alters her als die Sphäre des Menschlichen überhaupt angesehen wurde, nämlich die Sprache. Von 141 Minuten Film sind nur 40 Minuten von Dialogen begleitet. Kubrick erweist den Film als dasjenige Medium, in welchem die visuellen Mythen unserer Zeit kreiert werden. ...
The term cephalic sensory organ (CSO) is used for specialised structures in the head region of adult Opisthobranchia. These sensory organs show a high diversity in form and function, and the gross morphology of these organs differs considerably among taxa. They can be identified as cephalic shields, oral veils, Hancocks organs, lip organs, rhinophores or oral tentacles. Because of this extremely high diversity, the homology and the evolution of these organs have not been clarified yet. My intention was to use neuroanatomical data sets in order to find putative homologous CSOs. In this study, I will show data about immunohistochemical neurotransmitter content and cellular innervation patterns and their applicability as morphological characters for the homologisation of structures. I support earlier investigations that neurotransmitter content is often related to function. In contrast, axonal tracing patterns can be used to homologise nerves. Overall the aim of this study was to reconstruct the evolution of the CSOs of the Opisthobranchia, by projecting our neuroanatomical data sets onto a molecular phylogeny.
Baleen whales (Mysticeti) are a clade of highly adapted carnivorous marine mammals that can reach extremely large body sizes and feature characteristic keratinaceous baleen plates used for obligate filter feeding. From a conservation perspective, nearly all baleen whale species were hunted extensively over a roughly 100 years lasting time period that depleted many of the respective whale stocks with so far unknown consequences for e.g. their molecular viability. From an evolutionary perspective, the lack of fossil records together with conflicting molecular patterns resulted in a still unclear and debated phylogeny of modern baleen whales, particularly in rorquals (Balaenopteridae). In this dissertation, I will demonstrate the application of baleen whale genomes to tackle these open questions by using modern approaches of conservation and evolutionary genomics.
Conservation genomic aspects of baleen whales were addressed in two projects, both using whole genome data of either an Icelandic fin whale (Balaenoptera physalus) population or multiple blue whale (Balaenoptera musculus) populations to evaluate the impact of the industrial whaling era on their molecular viability. The results suggest a substantial drop in effective population size of both species but also a lack of manifestation in genotypes of the fin whale population when compared to the blue whale populations. Especially the rare and short runs of homozygosity (ROH), usually indicative for inbreeding, suggest frequent outcrossing in fin whales while all analyzed blue whale populations featured long and frequent ROH. In addition to these analyses, genome data of blue whale populations was further used to evaluate if northern hemisphere blue whales diverged into different subspecies. Population genetic and gene flow analyses showed clearly separated and well isolated populations in accordance with their assumed geographical distance. In contrast, the genome-wide divergence between all blue whale populations was low compared to other cetacean populations and to the next closely related sei whale species. Because this includes the morphologically different and well recognized pygmy blue whale subspecies, a proposal was made to equally categorize the two northern-hemisphere blue whale populations as subspecies.
Evolutionary aspects were addressed in a third project, by constructing the genome of the pygmy right whale (Caperea marginata) and testing its potential in phylogenetics and cancer research. Phylogenomic analyses using fragments of a whole-genome alignment featuring nearly all extant baleen whales, allowed the revision of the complex evolutionary relationships of rorquals by quantifying and characterizing the amounts of conflicts in early diverging branches. These relationships were further used to identify phylogenetically independent pairs of baleen whales with a maximum of diverging body size differences to compare rates of positive selection between their genomes. The results suggest nearly evenly distributed frequencies of alternative topologies which supports the representation of the early divergence of rorquals as a hard polytomy with high amounts of introgression and incomplete lineage sorting. Within the set of available genomic data, three independent pairs of baleen whales with diverging body sizes were found and comparisons of positive selection rates resulted in many potentially body size and cancer related genes. The lack of conserved selection patterns, however, suggest a more convergent evolution of size and cancer resistance like previously discussed in paleontology.
In conclusion, the application of whole genome data using methods of conservation genetics allowed for a comprehensive estimation about the molecular viability of blue and fin whales as well as an assessment of the taxonomic status of northern-hemisphere blue whale populations. The rather different results between blue and fin whales underlines the importance of genomic monitoring of baleen whales because different species show rather different molecular consequences of their potentially varying depletions. Furthermore, as showcased for the northern-hemisphere blue whale, many important isolated populations of baleen whales may still be unknown to conservation management and genome-wide comparisons will most likely contribute to overcome this under-classification problem. The application of whole genome data in evolutionary research allowed the characterization of the complex patterns of molecular conflicts within baleen whales and especially rorquals that will contribute to the still rather unclear understanding of their evolution. The here found molecular support for the idea of convergent evolution of gigantism in whales will further guide the search for molecular patterns responsible for Peto’s paradox.
Trotz der Annäherung der Begriffe 'Geschichte' und 'Evolution' unter dem Vorzeichen einer semantischen Verschiebung kulturellen Kapitals haben sich bis in die Gegenwart auch begriffliche Differenzen erhalten. So gibt es neben der unbekümmerten Anwendung von 'Geschichte' und 'Evolution' auf alle sich in der Zeit verändernden Dinge auch Versuche, die Begriffe terminologisch stark zu machen und in der Folge dessen 'Evolution' für den Bereich der Natur und 'Geschichte' für den der Kultur zu reservieren. Der Beitrag liefert eine historische Rekonstruktion dieser Entwicklung. Am Anfang stehen dabei einige quantitative sprachwissenschaftliche Beobachtungen zur Entwicklung der Häufigkeit der Begriffe in verschiedenen Textgattungen und zur gegenwärtigen Semantik durch einen Vergleich der häufigsten Genitivattribute. Im zweiten Abschnitt wird die Veränderung des Ausdrucks 'Geschichte' untersucht, zunächst in seiner terminologischen Bedeutung in den Geschichtswissenschaften, dann in seiner Ausweitung auf Gegenstände der Natur. Der dritte Abschnitt liefert eine analoge Untersuchung zu 'Evolution', ausgehend von den Naturwissenschaften und in der Ausweitung auf kulturelle Phänomene. Im vierten Abschnitt wird eine Verbindung der beiden Begriffe näher betrachtet, die im Sinne einer semantischen Verschränkung wirksam ist und sich unter anderem daraus ergibt, dass das Wort 'Evolution' eine teleologische Konnotation hat, die bei 'Geschichte' nicht vorliegt. Der fünfte Abschnitt schließlich beleuchtet die wissenschaftliche Stellung der Begriffe in der Gegenwart und erwägt die Aussichten ihrer terminologischen Differenzierung.
Revolution und Evolution
(2012)
Die Begriffsgeschichte der Termini Revolution und Evolution ist bereits ausführlich und vielerorts nachgezeichnet worden. Ins Blickfeld geriet jedoch selten ein Übertragungs-, Rückübertragungs- und Veränderungsprozess, der sich vor allem ab Mitte des 18. Jahrhunderts abspielte. Während dieses Zeitraumes prägte die Entdeckung der "geologischen Tiefenzeit" zunehmend den naturhistorischen Diskurs, und diese neue Zeit -Vorstellung überschnitt sich mit jener noch wirkmächtigeren politischen und geschichtsphilosophischen Zeit-Vorstellung, die durch die Französische Revolution ausgelöst wurde. Die Übertragungsprozesse von Revolution und Evolution überkreuzten sich in den Debatten der Aufklärung, und während eines bestimmten historischen Zeitraums strukturierten sie gemeinsam den Diskurs der "Geognosie" bzw. "Geogonie", wie zu dieser Zeit die Geologie avant la lettre zu meist genannt wurde. Die Herder’schen Ideen zur Philosophie der Geschichte der Menschheit können in diesem Kontext der Umbruchphase der Spätaufklärung als repräsentativ für diese semantischen Übertragungs- und Wanderungsbewegungen gelten, denn Revolution und Evolution sind entscheidende entwicklungslogische Interpretationskategorien in Herders geogonischem und geschichts-philosophischem Entwurf. Da Herder keinen Bruch zwischen Naturentwicklung (-geschichte) und Menschheitsentwicklung (-geschichte) sieht, sondern beides unter der Perspektive einer Fortschrittsidee subsumiert, gibt es bei ihm auch noch keine eindeutige Kategorisierung und Zuordnung von Evolution (zu Natur) und Revolution (zu Geschichte). Zugleich lassen sich die Mehrdeutigkeiten beider Begriffe sowie ihre sich beschleunigenden semantischen Verschiebungen besonders augenfällig am Beispiel des Herder'schen Textkorpus belegen, das aus diesem Grunde im Zentrum des vorliegenden Beitrags steht.
Retrophylogenomics in rorquals indicate large ancestral population sizes and a rapid radiation
(2019)
Background: Baleen whales (Mysticeti) are the largest animals on earth and their evolutionary history has been studied in detail, but some relationships still remain contentious. In particular, reconstructing the phylogenetic position of the gray whales (Eschrichtiidae) has been complicated by evolutionary processes such as gene flow and incomplete lineage sorting (ILS). Here, whole-genome sequencing data of the extant baleen whale radiation allowed us to identify transposable element (TE) insertions in order to perform phylogenomic analyses and measure germline insertion rates of TEs. Baleen whales exhibit the slowest nucleotide substitution rate among mammals, hence we additionally examined the evolutionary insertion rates of TE insertions across the genomes.
Results: In eleven whole-genome sequences representing the extant radiation of baleen whales, we identified 91,859 CHR-SINE insertions that were used to reconstruct the phylogeny with different approaches as well as perform evolutionary network analyses and a quantification of conflicting phylogenetic signals. Our results indicate that the radiation of rorquals and gray whales might not be bifurcating. The morphologically derived gray whales are placed inside the rorqual group, as the sister-species to humpback and fin whales. Detailed investigation of TE insertion rates confirm that a mutational slow down in the whale lineage is present but less pronounced for TEs than for nucleotide substitutions.
Conclusions: Whole genome sequencing based detection of TE insertions showed that the speciation processes in baleen whales represent a rapid radiation. Large genome-scale TE data sets in addition allow to understand retrotransposition rates in non-model organisms and show the potential for TE calling methods to study the evolutionary history of species.
Tuberaceae is one of the most diverse lineages of symbiotic truffle-forming fungi. To understand the molecular underpinning of the ectomycorrhizal truffle lifestyle, we compared the genomes of Piedmont white truffle (Tuber magnatum), Périgord black truffle (Tuber melanosporum), Burgundy truffle (Tuber aestivum), pig truffle (Choiromyces venosus) and desert truffle (Terfezia boudieri) to saprotrophic Pezizomycetes. Reconstructed gene duplication/loss histories along a time-calibrated phylogeny of Ascomycetes revealed that Tuberaceae-specific traits may be related to a higher gene diversification rate. Genomic features in Tuber species appear to be very similar, with high transposon content, few genes coding lignocellulose-degrading enzymes, a substantial set of lineage-specific fruiting-body-upregulated genes and high expression of genes involved in volatile organic compound metabolism. Developmental and metabolic pathways expressed in ectomycorrhizae and fruiting bodies of T. magnatum and T. melanosporum are unexpectedly very similar, owing to the fact that they diverged ~100 Ma. Volatile organic compounds from pungent truffle odours are not the products of Tuber-specific gene innovations, but rely on the differential expression of an existing gene repertoire. These genomic resources will help to address fundamental questions in the evolution of the truffle lifestyle and the ecology of fungi that have been praised as food delicacies for centuries.
The genus Bennelongia De Deckker & McKenzie, 1981 is most likely endemic to Australia and New Zealand and, up to now, only two described species in this genus had been reported from Western Australia. Extensive sampling in Western Australia revealed a much higher specifi c diversity. Here, we describe nine new species in three lineages, within the genus Bennelongia: B. cygnus sp. nov. and B. frumenta sp. nov. in the B. cygnus lineage, B. gwelupensis sp. nov., B. coondinerensis sp. nov., B. cuensis sp. nov., B. lata sp. nov. and B. bidgelangensis sp. nov. in the B. australis lineage, and B. strellyensis sp. nov. and B. kimberleyensis sp. nov. (from the Pilbara and Kimberley regions respectively) in the B. pinpi-lineage. For six of the nine species, we were also able to construct molecular phylogenies and to test for cryptic diversity with two different methods based on the evolutionary genetic species concept, namely Birky’s 4 x rule and the GYMC model. These analyses support the specifi c nature of at least four of the fi ve new species in the B. australis lineage and of the two new species in the B. pinpi lineage. We also describe Bennelongiinae n.subfam. to accommodate the genus. With the nine new species described here, the genus Bennelongia now comprises 15 species, but several more await formal description.
Ich kritisiere die Konzeption Amstutz’ aus einer Perspektive, die eine kulturelle Evolution im strikten Sinne als gegeben ansieht. Gemessen daran verspielt Amstutz den Nutzen evolutionären Denkens, indem er sich nur metaphorisch auf Evolution bezieht, ohne zugleich seinen Rechtsbegriff zu entwickeln. Das führt zu wissenschaftlich unbefriedigenden Aussagen, zumal saltationistische, quasi-lamarckistische und gruppenselektionistische Modelle genutzt werden, die weder für die biologische noch die kulturelle Evolution brauchbar sind.