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Coping with coprolites

Carl Mehling (USA) Generally, we have no use for it, or at least we convince ourselves we don’t, conveniently ignoring the fact that faeces of one kind or another (even our own) have fertilised our food for millennia. Organic waste products are an integral part of the living system and don’t tend to sit around for long. And it’s a good thing too, because, without the recycling of waste in Nature, we’d certainly be swamped by the stuff. Fig. 1. Ammonnite chamber steinkern composed of tiny invertebrate coprolites (Carl Mehling). Fig. 2. A probable Cretaceous crocodililian coprolites Fig. 3. The real thing? (Carl Mehling). Alas, this is a problem for students of coprolites – those droppings from Deep Time – as it reduces the probability of good coprolite fossils. However, everything in Nature has a story to tell, and there’s usually someone eager to listen, whomever or whatever that storyteller might be. I am one of those palaeontologists drawn to make order out of ordure and, thanks to the whims of the fossil record, enough of these now-inoffensive offerings have fortunately survived to the present. Fig. 4. A Triassic coprolite filled with fish bones (Carl Mehling). My first coprolite emerged from the Late Cretaceous marine sediments of Big Brook, New Jersey. It was a coprolite of spiral morphology – surprisingly common, once one’s search image is tuned – which my mentors credited to a shark. All ‘experts’, both amateur and academic, reflexively parroted this identification. Later, I learned that other … Read More

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Fossil fakes and their recognition

Joan Corbacho and Consuelo Sendino (Spain) Ever since fossils first attracted the attention of mankind, they have been traded and, with the emergence of this commerce, so fossil fakes have appeared. The number of such fakes and their geographical origin has increased with time. On the one hand, this parallels the large demand for fossils; on the other, it reflects the outlawing of fossil sales in some countries, combined with the economic needs of many families, who use fossils as their main source of income. This trend will continue, as the supply of genuine fossils diminishes due to trading restrictions. In particular, it will continue as borders, which were once freely open to nomadic movements become heavily policed, along with a decrease in open collecting sites. History of fossil fakes Fossils have been used for more than 400,000 years, some as tools and others as fertility symbols. For example, fossil echinoids were found in the early Neolithic site of Ain Ghazal in Jordan and at a Neolithic site in County Kerry in SW Ireland, where they were used as funeral adornments for ceremonial purposes. In addition, bracelets made of fossil shells were excavated at a Neolithic site in Vinca-Belo Brdo in Serbia. It is apparent from these examples that fossils were used by early Europeans to produce items of social value that could be traded. Therefore, it is not surprising that fossils have been faked for a long period of time. One of the most striking fossil frauds, rivalling in … Read More

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Fossils in amber (Part 2): Preparation and study

Dr David Penney and Dr David Green (UK) This is the second in a series of articles concerning fossils in amber. In the first, we focused on the biodiversity of organisms in the major deposits of the world, including the techniques available for distinguishing genuine fossils from fakes (see Fossils in amber (Part 1): Biodiversity). When the first fossil amber specimens were examined back in the 1600s, only very basic microscopy was available to examine the inclusions. In recent years, great progress has been made in amber preparation procedures, photomicroscopy and advanced imaging techniques, which can all now be employed in the study of fossils in amber. Optical properties of amber To understand the rationale for the preparation techniques described below, it is worth reviewing the way light passes through amber and the way that images are formed. Amber is usually transparent or translucent. The more transparent it is, the less the light is absorbed as it travels through the specimen. As opacity increases, more light is absorbed and inclusions become more difficult to see. Arthropod inclusions are visible because they have differing opacities and refractive indices to the enclosing amber. When light rays cross boundaries between media with different refractive indices (such as amber and air) they bend. If the surface is flat and polished, the light rays bend in a predictable manner and it is easy to see what lies within. If a surface is curved, irregular, undulating or scratched, the light rays bend in different directions, depending … Read More

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Urban geology: Palaeontology at the Wagamama restaurant, Amsterdam

Stephen K Donovan (The Netherlands) A misconception shared by many non-palaeontologists is that fossils are rare. For example, when governments pass legislation to protect their fossil heritage, they are stopping the export of complete and well-preserved specimens, such as those of Mesozoic dinosaurs, hominids and Ice Age mammoths. There can be little argument that protecting their prehistoric heritage is responsible. Yet, these same politicians will support, for example, the export of cement. This may seem unrelated, but, of course, limestone is rich in fossils, most particularly invertebrates (Bathurst, 1971), and is an essential component of cement. These fossils are not dinosaurs or mammoths, admittedly, but they are fossils nonetheless. Legislation needs careful wording to ensure that exporting cement is not an illegal activity. Fig. 1. Imported rocks used in raised flowerbeds and paving at Amsterdam Zuid (=south) railway station, the Netherlands. (A) General view. The grey stone is Carboniferous limestone; the pink stone is gneiss. The Wagamama restaurant is to the left of the photographer. (B) Detail of the upper surface of limestone on a raised flower bed. The fossils are dominantly fragments of crinoid and a colonial tabulate coral (Michelinia? sp.) is seen towards the bottom of the page and a section through a productid brachiopod(?) is right of the coin. The coin is €2, about 25mm in diameter.The Netherlands is an exporter of cement from the Upper Cretaceous limestone quarries in Limburg, in the far south of the country (Felder and Bosch, 2000) and therefore trades fossils in … Read More

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Fossils in amber (Part 1): Biodiversity

Dr David Penney and Dr David Green (UK) It is almost two decades since the original blockbuster movie, Jurassic Park, brought the existence of fossil insects in amber (fossilised tree resin) into the limelight. Since then, numerous books and research papers have been published. Fossiliferous amber deposits are still being discovered, including, in recent years, the first major deposits in Africa, India and Australia. The market for fossils in amber experienced a boom in the 1990s, but it has since declined for various reasons, including fakery, copal (sub-fossil resin) being sold as genuine amber and the current economic conditions. Nevertheless, there are many reputable sources for those wishing to develop their passion for amber – a substance that has fascinated people for millennia. It has been endowed with mystical, magical and medicinal properties, and used as an artistic medium and in jewellery. However, today, it is probably most famous for the fossil insect inclusions it preserves with life-like fidelity. It is these that are the focus of this article. This is the second part of a series of articles on fossils in amber. The first is: Fossils in amber (Part 1): Preparation and study. Important fossiliferous deposits There are almost 200 known amber deposits around the world, some dating from as early as the mid-Carboniferous. Relatively few have produced abundant biological inclusions and those that do occur only in strata of Tertiary or Cretaceous age. Many of these ambers were produced by different tree families under somewhat different environmental conditions. … Read More

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Geology and fossils of the Spilsby Sandstone Formation of Nettleton, Lincolnshire, UK

The Jurassic/Cretaceous boundary interval is represented in Lincolnshire by the Spilsby Sandstone Formation, a shallow water marine deposit that spans the Volgian stage of the Jurassic to the Berriasian stage of the Cretaceous (Hopson et al. 2008). The ammonite faunas of this formation are of particular interest, exhibiting affinities with correlative forms in both Russia on the Siberian plain, as well as Greenland and Canada (for example, Casey, 1973; Mikhail Rogov, personal communication 2015).

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Rare Cretaceous ichthyosaur from Lincolnshire

John P Green (UK) As many amateur and professional palaeontologists are aware, ichthyosaurs are well-known aquatic reptiles from the Mesozoic era, which are especially common in Jurassic marine deposits in the UK. They are particularly conspicuous in the Charmouth and Whitby Mudstone Formations of the Lias (Lower Jurassic), as well as the Oxford and Kimmeridge Clay Formations (Upper Jurassic). These horizons have yielded numerous complete and fragmentary remains that grace many private and museum collections across the UK. By contrast, the record of ichthyosaurs in Britain from the Jurassic/Cretaceous boundary interval is somewhat scanty, and only rare and fragmentary remains having been discovered. Any remains discovered from this time interval are therefore of great potential significance. Back in August 1995, during one especially hot summer’s day, I was fortunate to discover fragmentary ichthyosaur remains at a small quarry at Nettleton, Lincolnshire. This quarry exposed the Lower Spilsby Sandstone Formation, which is a shallow water marine deposit that embraces the Jurassic/Cretaceous boundary interval in Lincolnshire (Gaunt et al, 1992). Fig. 1. Locality map of the Castle Top quarry. Reproduced from Green and Lomax 2014; image originally reproduced. by permission of the council of the Yorkshire Geological Society. The specimen was discovered at a single horizon, 3.5m above the base of the formation, which (based upon stratigraphical grounds) falls within the ammonite zone, Subcraspedites preplicomphalus (Casey, 1973). This was formerly considered to fall within the Volgian stage of the latest Jurassic (Gaunt et al, 1992), although more recent work by Hopson et … Read More

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Barry’s secret dinosaurs

Ryan Clayton (UK) I have always been curious about footprints and trackways made by prehistoric animals, especially dinosaurs, due to the concept that the ground has captured the process of an animal, which is now long dead and their species extinct. I find it even more exciting when the creature that made the tracks is not known from physical remains, as it allows the opportunity for absolutely anyone subsequently to discover bones or even skeletons which can be associated with the preserved trace fossils. An ichnogenus (a genus only known from trace fossils) can be identified, but the actual physical profile of the animal remains a mystery. I’ve known for many years that, not far from the town of Barry in South Wales, there are trackways made by different dinosaur genera and sizes at Bendrick Rock. As a student studying less than 30km away, it would soon be a place I would explore as the workload calmed after my first year in 2015. On scanning the ground when visiting for the first time, I knew all I needed to do was find that first print with the iconic ‘three toes’ or tridactyl track. After that, every depression I could see was a footprint. The opportunity of being able to put my hand down on the same bit of ground on which a dinosaur had walked about 200Ma, which no one has any idea what it looked like, was, for me, extraordinary. Fig. 1. A photograph capturing the density of tracks … Read More

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Fossil crustaceans

Dr Neale Monks (UK) The crustaceans are the second biggest group of arthropods after the insects and have a good fossil record, but, for one reason or another, they are not as familiar to fossil collectors as the trilobites. It may be because they’re a bit harder to identify, with many of the most diverse groups being essentially microscopic, while the bigger ones like shrimps and crabs – arely get preserved in their entirety. But even if they’re difficult to identify, crustacean fossils are interesting and often make very attractive specimens. So that’s the theme of this article really – to draw your attention to these fossils and allow you to think a bit more deeply about what they were like and how t hey w ere all related to each other. Fig. 1. While most crustaceans are marine, a large number of crayfish live in freshwater, including crayfish. Crustacean origins The earliest crustaceans are known from Cambrian sediments including the well known Burgess Shale fauna. These primitive crustaceans are essentially worm-like in shape, but they do have many of the key features of crustaceans visible even on modern types such as shrimps. Their body is segmented, but the dorsal (back) part of each segmented was hardened into a thick, protective plate. Most segments bore a pair of appendages, one pair of legs and one pair of gills. This ‘biramous’ condition has been used to contrast the crustaceans (and also the trilobites) with the ‘uniramous’ insects and spiders that normally only … Read More

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Book review: Walking the Jurassic Coast: Dorset and East Devon: The Walks, the rocks, the fossils, by Ronald Turnbull

There are a lot of guide books to the Jurassic Coast Work Heritage Site. This one is intended to provide a useful introduction to the general geology of the coastline, dealing with its formation, fossils and plate tectonics (among many other things), but specifically in the context of walks – for both afternoon rambles and long distance hikes for the more committed.

Book review: A History of Life in 100 Fossils, by Paul D Taylor and Aaron O’Dea

I wouldn’t say I know Paul Taylor, but I did once go on a fieldtrip with him, organised by the Natural History Museum (NHM) in London, more years ago than I care to remember. It was to the Coralline Crag of Suffolk, which was chock full of bryozoans – Paul’s favourite niche fossil. And very interesting it was too – as was Paul. Therefore, I am not surprised how fascinating this book turns out to be.

Book review: Geology and Fossils of the Hastings Area (2nd ed), by Ken Brooks

I remember buying the first edition of Ken Brook’s fascinating little guide on Hastings a long time ago, and bumbling off to Hastings in the hope of finding Lower Cretaceous dinosaurs and tree ferns. Sadly, I was disappointed, as the area is not as productive as, say, the Dorset or North Yorkshire coastlines. Having said that, I have been back a few times armed with that first edition and have enjoyed the visits every time.

Book review: Early Miocene Paleobiology in Patagonia: High-Latitude Paleocommunities of the Santa Cruz Formation, by Sergio F Vizcaino, Richard F Kay and M Susan Bargo

Patagonia has not always been the cold, arid and dry place it is today. About 17mya – because the Andes were much lower allowing humid winds from the west to reach the area – it consisted of substantial forests and grasslands. It was also inhabited by strange and wonderful animals, many of which are now extinct, such as glyptodonts, huge snakes and the giant, tapir-like astrapotheres.

Book review: The Artists and The Scientists Bringing History to Life, by Peter Trusler, Patricia Vickers-Rich and Thomas H Rich

This fascinating book looks at the professional interaction over more than 30 years between a respected husband and wife team of US palaeontologists working for most of their professional lives in Australia (Prof Pat Vickers-Rich and Tom Rich) and a freelance artist (Peter Trusler), as he tries to interpret their work and bring to life ancient organisms and environments.

Book review: Amber: Tears of the Gods, by Neil D L Clark

Normally, I wouldn’t be interested in semi-precious stones and other pretty things. Personally, I prefer grubbing around in the dirt, perhaps for those far more beautiful, elusive and perfectly formed Cretaceous terebratulids or Silurian trilobites. However, some semi-precious stones have the advantage of also providing a tangible link to the ancient history of life.

Book review: Fossils in Amber: Remarkable snapshots of prehistoric forest life, by David Penney and David Green

Here at Deposits, we like our amber and this certainly isn’t the first book on the subject I have reviewed. In fact, over the years, we have published many articles on the fossilised sap and its inclusions, and have just finished publishing a short, two-article series by the authors of this excellent little publication.