The fossil had been in the collections of Doncaster Museum and Art Gallery for more than 30 years until Dean Lomax (25) palaeontologist and Honorary Scientist at The University of Manchester, uncovered its hidden secrets.
Dean first examined the fossil in 2008 when he noticed several abnormalities in the bone structure which made him think he had something previously unidentified. Working with Professor Judy Massare of Brockport College, New York, he spent over five years travelling the world to check his findings and a paper explaining the discovery is published today in the Journal of Vertebrate Paleontology.
Dean said: “After examining the specimen extensively, both Professor Massare and I identified several unusual features of the limb bones (humerus and femur) that were completely different to any other ichthyosaur known. That became very exciting. After examining perhaps over a thousand specimens we found four others with the same features as the Doncaster fossil.”
Similar-shaped to dolphins and sharks, ichthyosaurs, which are often misidentified as ‘swimming dinosaurs’, swam the seas of the earth for millions of years during the Triassic, Jurassic and Cretaceous periods, before being wiped out. The Doncaster fossil is between 189 and 182 million years old, from a time in the early Jurassic period called the Pliensbachian. It is the world’s most complete ichthyosaur of this age.
“The recognition of this new species is very important for our understanding of ichthyosaur species diversity during the early Jurassic, especially from this time interval, ” Dean added.
The research also looked at the size and age of the new species, and enabled a look at sexual differences (males and females). This included comparison with other groups of reptiles (living and extinct), whose limb bones are different between males and females, something that had never before been applied to ichthyosaurs. The limb bones of the Doncaster specimen were professionally prepared and removed, funded by the Esmée Fairbairn Foundation, as part of a grant awarded to Doncaster Museum Service.
The new species has been named Ichthyosaurus anningae in honour of the British collector, and woman in science, Mary Anning, who first collected ichthyosaurs in the early 1800’s. It is the first new Ichthyosaurus identified for almost 130 years.
Dean added: “Mary worked tirelessly to bring the ichthyosaurs, among other fossils, to the attention of the scientific world. Mary and her brother, Joseph, discovered the first ichthyosaur specimen to be scientifically recognised, collected at Lyme Regis around 1811.”
“It is an honour to name a new species, but to name it after somebody who is intertwined with such an important role in helping to sculpt the science of palaeontology, especially in Britain, is something that I’m very proud of. In fact, one of the specimens in our study was even found by Mary herself! Science is awesome.”
“This discovery shows that new species, and not only ichthyosaurs, are awaiting discovery in museum collections. Not all new discoveries are made in the field.”
Manchester University – Header Image : Life restoration of Ichthyosaurus anningae – Artwork by James McKay
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Back then temperatures were 2-4 degrees C warmer than present. Their results have just been published in the scientific journal Geology, and are important as we are rapidly closing in on similar temperatures.
While the world is preparing for a rising global sea-level, a group of scientists led by Dr. Nicolaj Krog Larsen, Aarhus University in Denmark and Professor Kurt Kjær, Natural History Museum of Denmark ventured off to Greenland to investigate how fast the Greenland Ice Sheet reacted to past warming.
With hard work and high spirits the scientists spent six summers coring lakes in the ice free land surrounding the ice sheet. The lakes act as a valuable archive as they store glacial meltwater sediments in periods where the ice is advanced. That way is possible to study and precisely date periods in time when the ice was smaller than present.
– It has been hard work getting all these lake cores home, but is has definitely been worth the effort. Finally we are able to describe the ice sheet’s response to earlier warm periods, says Dr. Nicolaj Krog Larsen of Aarhus University, Denmark.
Evidence has disappeared
The size of the Greenland Ice Sheet has varied since the Ice Age ended 11,500 years ago, and scientists have long sought to investigate the response to the warmest period 8,000-5,000 years ago where the temperatures were 2-4 °C warmer than present.
– The glaciers always leave evidence about their presence in the landscape. So far the problem has just been that the evidence is removed by new glacial advances. That is why it is unique that we are now able to quantify the mass loss during past warming by combining the lake sediment records with state-of-the-art modelling, says Professor Kurt Kjær, Natural History Museum of Denmark.
16 cm of global sea-level rise from Greenland
Their results show that the ice had its smallest extent exactly during the warming 8,000-5,000 years ago – with that knowledge in hand they were able to review all available ice sheet models and choose the ones that best reproduced the reality of the past warming.
The best models show that during this period the ice sheet was losing mass at a rate of 100 Gigaton pr. year for several thousand years, and delivered the equivalent of 16 cm of global sea-level rise when temperatures were 2-4 °C warmer. For comparison, the mass loss in the last 25 years has varied between 0-400 Gigaton pr. year, and it is expected that the Arctic will warm 2-7 °C by the year 2100.
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Leading marine biologists collaborated in the study – the most detailed ever conducted into the genetic structure of the bottlenose dolphin population in the Mediterranean to date – and the results have been published in the journal Evolutionary Biology.
Tissue samples from 194 adult bottlenose dolphins (Tursiops truncatus) were collected between 1992 and 2011 from the five main eastern Mediterranean basins.
The team’s aim was to investigate the population structure and historical processes that may be responsible for the geographic distribution of the species in that area. No other study has compared the fine scale genetic structure within the Mediterranean, with the well described genetic structure in the North Atlantic.
The Mediterranean basin in particular is a global biodiversity hotspot and several marine species exhibit complex population structure patterns over relatively short geographic distances. It is therefore a particularly interesting region for scientists to investigate the drivers of population structure in marine organisms.
One of the study’s lead authors Dr Andre Moura, from the School of Life Sciences, University of Lincoln, UK, said: “As a consequence of the bottlenose dolphin only colonising the Mediterranean after the last glacial maximum or Ice Age, population structure in the Mediterranean mainly arises from the different colonisation routes the various early colonisers took, and the genetic varieties they carried.
“Similar to the North Atlantic, two ecological types are likely to exist, one occupying deep ‘pelagic’ – or away from the coast – waters, and another occupying ‘coastal’ shallow water areas. By comparing our results with genetic data from previous studies on Atlantic bottlenose, we concluded that bottlenose dolphin in the North Atlantic, Mediterranean and North Sea are likely to represent a single metapopulation – This is a particular type of population structure, when a single population is subdivided into regional subgroups that exchange individuals at varying rates. These results have important implications for the understanding and conservation of Mediterranean biodiversity.”
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The Arts and Humanities Research Council (AHRC) funded the three-year project directed by Professor Mark Ormrod, of the University of York’s Centre for Medieval Studies, who headed a team of researchers based in York and London.
It reveals evidence about the names, origins, occupations and households of a significant number of foreign nationals who chose to live and work in England in the era of the Hundred Years War, the Black Death and the Wars of the Roses. The project contributes to debates about the longer-term history of immigration to Britain, helping to provide a deep historical and cultural context to contemporary debates over ethnicity, multiculturalism and national identity.
The database contains the names of a total of 65,000 immigrants resident in England between 1330 and 1550. In one year, 1440, the names of 14,500 individuals were recorded – this at a time when the population of England was approximately two million.
Taking into account gaps in the records, the researchers estimated that one person in every hundred was a foreign national. They were found in all counties, from Cornwall to Northumberland, in hamlets as well as in major ports. Their nationalities ranged from people from other parts of the British Isles, including Scots, Irish and Channel Islanders, to mainland Europeans from Portugal to Sweden, from Greece to Iceland.
In many cases the occupation of the individual is known, from highly skilled craftsmen such as goldsmiths, to weavers – many of whom were Flemish – to agricultural labourers. Three Flemish weavers from Diest in Belgium lived and worked in St Ives, Huntingdonshire, in the 1330s; and John Lammyns, a goldsmith from Antwerp, lived in Bristol in the 1430s and 1440s.
The research reveals that aristocratic households brought back foreign servants from English-occupied France at the end of the Hundred Years War: Sir John Montgomery of Faulkbourne, Essex, had five foreigners working in his household in the 1440s. Many ordinary families of traders, artisans and workers chose to migrate to England. Walter, a minstrel from Germany, settled in London in the late fifteenth century with his entire family, including his mother, wife, three sons and three daughters.
One of the surprises revealed by the research is the number of resident immigrants who lived and worked in rural areas, rather than in towns and cities. The research reveals how such people integrated – and sometimes clashed – with English people, suggesting much about how our ancestors used language, dress and behaviour as symbols of national identity.
Professor Ormrod says: “The England’s Immigrants project transforms our understanding of the way that English people and foreign nationals, of all levels of society, lived and worked together in the era of the Plantagenets and early Tudors. The research provides a deep historical context for modern debates about the movement of peoples and the state’s responsibilities to regulate immigration.”
The database is accessible to all at www.englandsimmigrants.com and is a fully searchable and interactive resource, from which data can be downloaded. The website also supports the researcher with guides to the various counties and documents, and provides case studies of interesting individuals demonstrating just how much we can learn from our immigrant ancestors.
Despite notable differences in appearance and governance, ancient human settlements function in much the same way as modern cities, according to new findings by researchers at the Santa Fe Institute and the University of Colorado Boulder.
Previous research has shown that as modern cities grow in population, so do their efficiencies and productivity. A city’s population outpaces its development of urban infrastructure, for example, and its production of goods and services outpaces its population. What’s more, these patterns exhibit a surprising degree of mathematical regularity and predictability, a phenomenon called “urban scaling.”
But has this always been the case?
SFI Professor Luis Bettencourt researches urban dynamics as a lead investigator of SFI’s Cities, Scaling, and Sustainability research program. When he gave a talk in 2013 on urban scaling theory, Scott Ortman, now an assistant professor in the Department of Anthropology at CU Boulder and a former Institute Omidyar Fellow, noted that the trends Bettencourt described were not particular to modern times. Their discussion prompted a research project on the effects of city size through history.
To test their ideas, the team examined archaeological data from the Basin of Mexico (what is now Mexico City and nearby regions). In the 1960s — before Mexico City’s population exploded — surveyors examined all its ancient settlements, spanning 2000 years and four cultural eras in pre-contact Mesoamerica.
Using this data, the research team analyzed the dimensions of hundreds of ancient temples and thousands of ancient houses to estimate populations and densities, size and construction rates of monuments and buildings, and intensity of site use.
Their results, published in the new AAAS open-access journal Science Advances this month, indicate that the bigger the ancient settlement, the more productive it was.
“It was shocking and unbelievable,” says Ortman. “We were raised on a steady diet telling us that, thanks to capitalism, industrialization, and democracy, the modern world is radically different from worlds of the past. What we found here is that the fundamental drivers of robust socioeconomic patterns in modern cities precede all that.”
Bettencourt adds: “Our results suggest that the general ingredients of productivity and population density in human societies run much deeper and have everything to do with the challenges and opportunities of organizing human social networks.”
Though excited by the results, the researchers see the discovery as just one step in a long process. The team plans to examine settlement patterns from ancient sites in Peru, China, and Europe and study the factors that lead urban systems to emerge, grow, or collapse.
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