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Taxonomy, evolutionary history, and ecological dominance of Themeda and Heteropogon.
No full textHeteropogon and Themeda grasses are common and significant components of the C4 savannas which have recently gained more attention for conservation and biodiversity research. The two genera have been the subject of ecological research due to their widespread and dominant species H. contortus and T. themeda. Like many tropical plant lineages, however, in-depth knowledge necessary for the management of these ecosystems is still lacking. This thesis focuses on the diversity of Heteropogon and Themeda in respect to evolution, ecology, and systematics. In this thesis, phylogenetic analyses indicated that the evolutionary history of Heteropogon and Themeda is being driven by complex evolutionary processes and their origin is dated back to the Miocene grassland expansion. I interpreted those discordant phylogenetic placements between plastid and nuclear trees as underlying polyploidization or hybridization within the groups. Dating analyses indicated that most species originated in the Miocene grassland expansion. Widespread species, H. contortus and T. triandra did not originate until the Late Miocene and quickly spread throughout the Tropics in the Pleistocene. Climatic niche characteristics and geographic distributions of Heteropogon and Themeda shed light on macroecological patterns, adaptation by functional traits, and the evolution of climatic niche and functional traits. I found that Heteropogon and Themeda species are separated into savanna and wetland groups. This is supported by differences in precipitation regimes of the two habitats and functional traits (e.g., plant height, leaf area, and awns). In an evolutionary context, biomes were shifted from savannas to wetlands, and niche divergence occurred. Functional traits changed by habitat preferences and show lability in the lineage. Integration of morphology and new ecological and phylogenetic evidence derived from this thesis were used in new generic and species reclassifications of Heteropogon and Themeda. I conclude that the generic description of Heteropogon should be narrowed, and I accept three species, while that of Themeda expanded to accept 26 Themeda species and 2 varieties. Phylogenetic relationships determine diagnostic morphological characters in generic and species delimitations. This new systematics of Heteropogon and Themeda demonstrates how to apply various biological data in taxonomic revision, and to summarize biodiversity information of Heteropogon and Themeda
On the reliability of historic books as sources of reference samples of early synthetic dyes – The case of “The Coal Tar Colours of the Farbwerke vorm. Meister, Lucius & Brüning, Höchst on the Main, Germany – A General Part” (1896)
No full textThe swatches present in the popular book “The Coal Tar Colours of the Farbwerke vorm. Meister Lucius & Brüning, Höchst on the Main, Germany – A General Part”, published in 1896, were analysed by high performance liquid chromatography coupled to diode array detector and high-resolution tandem mass spectrometry (HPLC-DAD-MS/MS) with the aim to identify the synthetic dyes and reveal the correspondences and discrepancies between the information reported in the labels and the actual chemical composition of the samples.
The research resulted in guidelines to be followed to connect commercial dye names with Colour Index (C.I.) constitution numbers and produced a molecular database of more than 250 molecules, whose high-resolution mass spectrometric details are reported here for the first time in some cases. Out of 120 samples analysed, ca. 40% did not exactly correspond to the expected dye(s) according to the labels, thus raising awareness of the challenges related to the reliability of historic sources of reference materials and the need to study the composition of these historic samples before using them for chemical research purposes. Furthermore, molecular databases of synthetic dyes are fundamental for the correct identification of these materials in historic textiles, objects and works of art. Thus, the results of this research are extremely useful to all researchers studying dyed objects produced from the second half of the 19th century onwards
Telipogon leisberthvelezii (Orchidaceae: Oncidiinae), a new orchid species from the Cordillera del Cóndor in Ecuador.
No full textA Computed Tomographic Study of the Premolar Teeth of Babyrousa spp.
No full textA photographic and computed tomography (CT) scanning study was carried out on the premolar teeth of 18 adult male Babyrousa babyrussa skulls, 10 skulls of Babyrousa celebensis, including 6 adult males, 1 adult female, 1 subadult male, 1 subadult female, and 1 juvenile male. The occlusal morphology of the permanent maxillary premolar teeth of B. babyrussa was very similar to that of B. celebensis. Almost all the maxillary third premolar teeth (107/207) had 2 roots, whereas maxillary fourth premolar teeth (108/208) had 3 or 4 roots. All of the mesial tooth roots of 107/207 and 108/208 were tapering rod-like structures; each contained a single pulp canal. Almost all distal roots of 107/207 were “C” shaped and contained 2 pulp canals. The 108/208 palatal roots were “C” shaped and contained 2 pulp canals. The mesial and distal roots of the mandibular third premolar teeth (307/407) teeth were uniformly rod-like, as were the mesial roots of the mandibular fourth premolar teeth (308/408) teeth. The distal roots of the 308/408 teeth were “C” shaped. All B. babyrussa 307/407 teeth have a single pulp canal located in each of the mesial and distal roots. The 308/408 mesial tooth root contained 1 pulp canal. In all but 3 of the 36 distal 308/408 roots of B. babyrussa teeth and in 7 of the 14 distal roots of B. celebensis teeth there was a single pulp canal; in the other 7 teeth there were 2 pulp canals. Each of the 3 medial roots contained 1 pulp canal
Collecting Revolution: George Thomason and the ‘Thomason Tracts’
No full textThe approximately 24,000 pamphlets, manuscripts and newspapers collected by the London bookseller George Thomason are an invaluable source for the study of the political events of 1640 to 1663. This introduction surveys the articles, based on a conference held at the British Library, which are brought together in eBLJ 2023
Light-sensitive short hypocotyl genes confer symbiotic nodule identity in the legume Medicago truncatula.
No full textNew and poorly known taxa of Indigofera (Fabaceae, Papilionoideae, Indigofereae) from the Pondoland Centre of Endemism, South Africa: Part 2.
No full textAn ancient Mesopotamian herbal.
No full textThroughout the world, traditional medical systems continue to be important to healthcare. They vary greatly in their underlying beliefs, but almost all share the use of herbal medicines as a central practice. Ancient Mesopotamia – the area of modern-day Iraq and adjoining regions – offers a special opportunity to study such medical practice in antiquity. Many thousands of clay tablets survive, some over 5,000 years old, bearing texts relating to life in the past. Drawing on the expertise of Assyriologists, botanists and archaeologists, An Ancient Mesopotamian Herbal explores the deep history of plants in traditional medicine and offers a groundbreaking reassessment of existing research. Combining methods from the humanities and science, the authors provide a concise overview of ancient Mesopotamian culture and herbal lore, along with new identifications of Assyrian and Babylonian herbal medicines, focusing on 25 case studies
