The Winter Programme Synopses from 2016-2017
Wednesday October 5th 2016
Dr James Neenan Oxford University Museum of Natural History
The Evolution of Placodont Marine Reptiles from the Triassic of Europe and China
Placodonts were a group of durophagous sauropterygians that inhabited the eastern and western margins of the Tethys Ocean from the lower Middle to the end Triassic. The group consists of two morphotypes: the plesiomorphic, paraphyletic, and unarmored 'placodontoids', which are known only from the Middle Triassic, and the heavily armored Cyamodontoidea, which span the entire Middle and Late Triassic. However, the evolutionary relationships and origins of the Placodontia have remained unclear until now, particularly in the light of new taxa described from China. In order to resolve the systematic relationships of placodonts, computed microtomographic (µCT) scanning and virtual 3D reconstruction was used on several crania from both European and Chinese taxa. This method not only allows accurate reconstruction of external osteology, but also of obscured structures such as the braincase and inner ear. For the first time, this has allowed the reconstruction of evolutionary relationships for all placodont genera. Additionally, a new, exquisitely preserved skull of a juvenile placodontiform from Winterswijk, the Netherlands has provided a wealth of evidence concerning both the palaeogeographic and evolutionary origins of the placodonts. Characters such as a single row of teeth on the palatine place the new taxon on the stem to Placodontia, indicating an origin of the clade in the western Tethys, which then radiated eastwards. Furthermore, the dentition is not adapted for durophagy, indicating the unusual dental arrangement of palatine teeth in placodonts did not initially evolve as a result of consuming hard-shelled prey. As the most plesiomorphic clade of the most successful and diverse marine reptile radiation known, the placodonts are essential for understanding the origins and diversification of Sauropterygia. The new data are therefore of great significance, providing insight into the palaeobiogeographic and palaeoecological changes that occurred on the stem leading to the more derived sauropterygians.
Wednesday October19th 2016
Dr Juan Carlos Berrio University of Leicester
Evolution of Neotropical flora during the Neogene and Quaternary periods
Tropical mountains are regarded as the most diverse ecosystem of the world. In northern South America, the tropical Andes have a characteristic altitudinal gradient which controls the distribution of climatic conditions, thus creating distinctive vegetation patterns, and plant diversity. The fossil pollen evidence from the paleo-lake at the High Plain of Bogota, and its surroundings, reveals the evolution of Neotropical flora associated with the development of the Andean mountains. The environmental history of the northern Andes starts between 34 million and 65 million years ago (Ma), when the tectonic plate that dives under the Pacific edge of South America began an orogenesis, changing the shape of northern South America dramatically, with a consummate effect on the regional climates. The northern South American lowlands was once part of a much larger 'pan-Amazonian' region, which, before the late Miocene (until 10 Ma), included the area of the present Amazon, Orinoco, and Magdalena, drainage basins. The term 'pan-Amazonia' refers to a vast area which contains diverse faunal fossils that are now restricted to Amazonia. During the middle-to-late Miocene period, the vegetation, established on the “proto”-Andes, consisted of tropical lowland forests, with some Gondwanan families predominant (Nothofagus, Araucaria, Gunnera, and Winteraceae). However, the most intense Andean mountain building was during the late middle Miocene (~12 Ma) and early Pliocene (~4.5 Ma). Plate-tectonics ultimately resulted in the closing of the Panama Isthmus during the Pliocene (at ~3.5 Ma); and led to the Great American Biotic Interchange. During the early Pliocene, the number of tropical lowland taxa decreased; and the taxa of present-day Andean, and sub-Andean, vegetation increased, suggesting the first stage of uplift to approximately 1000±500m elevation. In middle Pliocene time, the predominance of Andean, and sub-Andean, taxa (Podocarpus, Ilex, Hedyosmum etc), constituted 50-60% of the regional vegetation. This suggests that the Andes had reached, by then, an altitude of approx. 2000±500m. Phyto-geographically, the composition of the middle Pliocene vegetation was characterised by a predominance of wide tropical- and Neotropical-taxa. During the late Pliocene, the Andes uplifted to approx. 2200±500m elevation. The wide tropical- and Neotropical-species showed a considerable decrease; whereas taxa with a wide-temperate origin, dominated the fossil assemblage. The composition of the late-Pliocene Andean forest differed from that of late-Quaternary age. The absence of certain taxa, which migrated in to South America during Pleistocene times, such as Alnus, Juglans and Quercus is apparent. The progressive uplift of the Andean mountains in northern South America promoted the development of alpine vegetation (the so-called Paramo vegetation and grass Paramo). Today, we can find this typical ecosystem occurring at altitudes between 3200 and 4000 m; with characteristic taxa such as Espeletia (Asteraceae), Hypericum, Acaena-Polylepis (as indicators of the upper Forest Line (UFL), Ericaceae (incl.Vaccinium) amongst others, and the grass Paramo, with Poaceae, Caryophyllaceae and Aragoa.
Wednesday November 2nd 2016
Prof Mike Stephenson British Geological Survey
1769 all over again? Energy resources in the developing world, how we’ll never get to a two degree world, and what we should do about it.
Before 1700, fossil fuels had already overtaken wood as the leading provider of heat in the homes of British people. Plentiful coal in the north of England enabled the natural supply of non-fossil energy to be bypassed. So began what has been called, by the historian Andreas Malm, the ‘fossil economy’ or the burning of carbon that came not from local growing sources (trees) but from wood 330 million years old. Next came the steam engine (1769). Not long after (from 1781), cotton manufacture, previously based near fast-flowing streams, became independent of water when the rotative steam engines of Boulton and Watt led to the growth of large, steam-powered mills concentrated in towns like Manchester and Salford. Steam engines for winding gear and pumps followed, and meant that even more coal could be mined. This start of the fossil economy might also be seen as the start of the latest of the geological epochs – the Anthropocene, marked geochemically by, amongst others, the rise in CO2, as recorded in ice cores. That relationship with coal is weaker in Britain today where most of our electrical power, at least, is today generated by gas. But coal continues to be used elsewhere in the world. Predictions like those of the International Energy Agency (IEA) suggest that coal will continue to be used heavily in the future, and will probably be important for global electricity generation for many years to come. According to the most recent IEA forecast, coal demand will grow to 5814 million tonnes per year through 2020, a rate of 0.8% per year on average. Half of the growth, 149 Mt, will be in India. With all this coal burning how are we going to get to the 2°C limit set at the 2015 United Nations Climate Change Conference, COP 21, concluded in Paris in December? What technologies can be used? And if we can’t get to a ‘two degree world’ what does science tell us about being able to adapt?
Wednesday November 16th 2016
Dr Carys Bennett University of Leicester
Habitats and environments of the early Carboniferous tetrapod world
The TW:eed Project Project (Tetrapod World: early evolution and diversification) examines the rebuilding of terrestrial ecosystems following a major extinction at the end of the Devonian. At this time tetrapods were undergoing a range of innovations to become the first vertebrate animal to walk on land. The project focuses on the Tournaisian Ballagan Formation that was deposited in a coastal to alluvial setting. Study sites include inland and coastal localities from the Scottish Borders region and a 500 metre deep borehole drilled in 2013. During the last four years the team have found a wealth of tetrapod, fish and invertebrate fossils that disprove the theory that there was a gap in the fossil record (Romer’s Gap) after the extinction. Instead, a diverse range of new tetrapod species and other animals became established shortly after the extinction. The fossil record gap is likely due to collections bias and people not knowing where to look. The most common lithology preserving tetrapods is sandy siltstone, deposited in seasonal flooding events as cohesive flows. This facies usually overlies palaeosols and can be difficult to identify in the field. However, it contains the most fossil-rich deposits in the early Carboniferous, including lungfish, ray-finned fish, sharks, bivalves, ostracods, millipedes, scorpions and abundant plant remains. Using sedimentology, geochemistry (carbon isotopes) and micropalaeontology, my research explores what the ancient landscape looked like and how that changed over time. Encompassing river systems, evaporitic lakes, vegetated marshes, dry desiccated plains and monsoonal floods, the landscape was dynamic. Through time the environment was ever-changing and periodically subject to short-lived marine incursions onto the floodplain. This dynamic setting was important in influencing the evolution of tetrapods as they became fully terrestrial. You can find out more about our project and see photos of our recent excavation and museum exhibit here: www.tetrapods.org.
Wednesday November 30th 2016
Xiaoya Ma (Dept Earth Sciences, NHM, London; & Yunnan Key Lab. for Palaeobiology, Yunnan Uni. Kunming, China)
Fossil Brains from the Cambrian Chengjiang biota.
Comparative studies of nervous systems and sensory organs are fundamental for understanding the evolutionary relationships between major animal groups and their ecological adaptation throughout evolutionary history. Exceptionally [well] preserved Cambrian panarthropod fossils provide a rich and underexploited source of data pertaining to neural and sensory organisation during the early sages of their radiation.
Recent reports of the brain and other neural structures of Cambrian pan arthropods demonstrate that these ancient animals had acquired complex central nervous systems (CNS) and sensory organs by 517 Ma, and that the two main configurations of the brain and eyes, observed in extant arthropods (Mandibulata & Chelicerata), had already evolved. The neural structures, identified in a Cambrian stem-euarthropod anomalocaridid, provide direct evidence for the segmental affinity of its frontal appendages, shedding light on the origin of the euarthropod CNS. However, scarcity of fossilised neural tissue has meant that most studies to date have been based on single specimens, hindering tests of fidelity of those structures, and [the] understanding [of] the diagenetic processes that led to their exceptional preservation. Geochemical analyses provide crucial insight into neural tissue preservation, revealing that the neural tissue was initially preserved as carbonaceous film, and subsequently pyritized. This mode of preservation is consistent with the taphonomic pathways of gross anatomy, indicating that no special mode is required for the fossilisation of labile neural tissue. Preliminary decay experiments also support the preservation potential of neural structures and their morphological interpretation after compression.
Monday January 9th
Parent Body Lecture, New Walk Museum, Leicester
Paul Denton British Geological Survey
Ground-shaking education: using seismic signals to educate and inspire.
Wednesday January 18th 2017
Dr Alex Liu University of Cambridge
Decoding the fossil record of early animal evolution.
The evolution of animals was one of the most important biological events in the history of life on Earth, not only because it paved the way for our own existence, but because animals have had an enormous, and irreversible, impact on the biosphere. In recent years, the focus of palaeontological studies into the initial evolution, and radiation, of animals, has centred on the fossil record of the late Ediacaran Period, which shows diverse communities of unusual organisms that lived between 580 and 541 million years ago. Determining what these fossilised organisms were (i.e. animals, plants, algae or an entirely unique Kingdom of Life), has proven very difficult; and is one of the most controversial topics in palaeontology. In this talk, I will outline the current state of knowledge surrounding the Ediacaran biota, and will discuss new findings and discoveries being made across the globe.
Charnwood has been integral to past Ediacaran research, and ongoing research into key fossils suggests that it may prove extremely informative in the search for evidence for early animals in the rock record.
Wednesday February 1st 2017
Dr Gawen Jenkin (Department of Geology, University of Leicester)
The Mine of the Future: Can we get metals out of the ground in a "green" sustainable way?
I will first examine the ongoing need for mineral resources to underpin a good quality of life for the population of planet Earth. Although we might ultimately develop a “circular economy” this is a long way off, and we will need to continue to extract minerals for many years to come. However, the mining industry is under a variety of pressures, both geological and anthropogenic, which make it ever harder to operate economically. At the same time the industry needs to be moving to more sustainable operations, in particular, reducing carbon emissions. I then described an exciting breakthrough technology developed at the University of Leicester – ionic liquids – that has the potential to revolutionise the processing of mineral ores to metals, in a green and environmentally-benign way.
Wednesday March 1st 2017
Dr Erwan Le Bee (University of Leicester)
High Impact Drilling: Chicxulub and its' peak ring.
Sixty-six million years ago, an asteroid hit our planet and formed the 200 km diameter Chicxulub impact crater, now buried underneath Cenozoic sediments of the Yucatán Peninsula in Mexico. It is one of the best preserved large impact structure on Earth and also has an unequivocal peak ring - an inner ring formed of hills, more commonly observed in large impact structures on rocky bodies of our solar system.
During 2016 the International Ocean Discovery Program (IODP) Expedition 364 drilled into the peak ring of the Chicxulub impact crater, offshore Mexico. A total of 303 cores were recovered, from the carbonate sedimentary rocks infilling the crater as well as the peak ring itself, and the single hole reached a depth of 1334 meters below the sea floor. An international team of scientists is researching the material and data collected during this expedition. After the initial sampling and analyses took place offshore Mexico in April and May 2016, the cores were sent to the IODP Core Repository in Bremen, Germany for further analysis from September to October 2016.
A recent publication from the science team, published in the journal Science, confirmed a model for how peak rings form in large impact structures using the drill core observations at the Chicxulub crater for evidence, and extending these findings to formation models for craters on other planetary bodies. The ongoing research will shed further light on peak rings, including how the target rocks were affected by the impact and what could be the positive and negative effects on life after the impact. The Chicxulub impact is well known to be associated with a major extinction event, killing ~75% of species on Earth including the dinosaurs. By looking at sediments recovered directly above the peak ring, the science party also aimed to understand how the biosphere reacted and recovered following the impact.
The presentation traced the history of the Chicxulub impact crater, from the postulation of its existence to its discovery and to the recent IODP Expedition 364. It aimed to provide a behind-the-scenes look at the operations to recover core, and other data, from over a kilometre beneath the present-day sea bed; thus giving insight into the excitement of scientific drilling and discovery.
IODP Mission-Specific Platform Expedition 364 was organised by the ECORD (European Consortium for Ocean Research Drilling) Science Operator: the British Geological Survey, the European Petrophysics Consortium (Universities of Leicester(lead), Aachen and Montpellier) and MARUM, Germany.
Saturday March 11th
Annual Saturday Seminar, University of Leicester
Geology in Space
Wednesday March 15th
Prof Jane Evans British Geological Survey
RICHARD III- analysing the skeleton of a King.
Wednesday March 15th