Thursday, 23 December 2010

Dusty Dinosaurs


Although Christmas is upon us, I thought that I would have a little grumble this week. Not too much of a moan because I think that would be a bit unfair but it is something I’ve been observing for quite a while and, since last week, has almost become an embarrassment.

I’ve spent quite a bit of time at the Natural History Museum (NHM) in London over the last few years and I love the place. More often than not, it is for comparative study of fossil bones, to take digital images for the same purpose and also for this blog. I also go for the atmosphere that the building brings, and what a magnificent building it is – simply stunning.

Normally my first point of call is to go and look at the dinosaurs although, on this particular visit, it was to have a good look at the marine reptile gallery and examine a couple of specimens. So I arrived at the museum and, just like most visitors do, promptly headed for the Dinosaur Gallery and have yet another wander around.

On this occasion I walked in and straight away came upon the casts of Camarasaurus and Triceratops. As usual just their presence is enough to create that immediate sense of awe and wonderment and I got my camera out ready to start taking images.

I gazed at the scapulocoracoid of Camarasurus. At first in wonder at the size of these great shoulder blades and then, in amazement, at the amount of dust that was covering these cast bones. I looked up and around the great sauropod and, in the subdued museum lighting, I could see that the entire skeleton was caked in dust. Frankly, it looked awful and I quickly moved on to the Triceratops mount.

This cast was also in a filthy state but had an additional problem. Some of the exhibits are surrounded by toughened glass barriers which are obviously there to stop people from touching the bones or causing them damage. This makes sense but looking at the glass, you would be hard pressed to guess when it had been last cleaned. It was covered in fingerprints, misted over in many places and severely impaired ones view of the specimen. Truly disgusting.

A bit dark but you get the idea
I left the trike and climbed the stairs that were situated behind the camarasaur. I looked down on the sauropod and again was horrified at the amount of dirt on display. This was the pattern throughout the rest of my tour of the gallery. It didn’t matter where you looked, the overall condition of the specimens, the platforms where they were mounted, the glass barriers and displays was, frankly, shocking. I took quite a few images and later, when I downloaded them to the computer, the problem becomes even worse because of the flash.

Surely something needs to be addressed here. Keeping the museum and exhibits clean demonstrates a museum that has a sense of duty and cares for its collection. At the same time it also sends a valuable and positive message to the public, donors and supporters alike.
Like so many museums the NHM is centrally located in a city environment and there are a number of pollutants that cause problems. In this case, and one suspects that all museums have the same problem, dust is the number one issue. It permeates from the exterior, a combination of dirt, soot, soil and other nasties, and then combines with human skin and hair to settle throughout the interior and on the exhibits.

It continues to build up and become unsightly. Dust can also absorb moisture and create humidity which can damage specimens. It can also stain, attract pests and carry pollutants with it. It can even be abrasive when wiped off of delicate objects. Dust needs to be controlled.

I understand that in these times of austerity that the funds or indeed the inclination is not there to become proactive with regards to dust control or to even manage a simple cleaning regime. I don’t pretend to have all the answers either. I mean – how do you clean and dust a sauropod skeleton? With a vacuum cleaner and lots of extensions? Feather dusters? Will a scaffold be necessary? What are the health and safety implications? I do realise the problems. I do understand that only trained museum staff can do the job.

And yet something does need to be done. Surely regular cleaning in the museum is good management practice? The amount of dust on these specimens must amount to a few years of build up now and frankly it is unacceptable for the exhibits in a national museum to be in such a state and I hope something will be done soon to alleviate the problem.

That just leaves me to wish all of you who celebrate it, a very happy and peaceful Christmas.


Dusty dromaeosaurs!


Wednesday, 15 December 2010

Quarry 4 Produces


July arrived and I was due to head south again but the news that the Cuckoo’s Hole quarry was closed knocked the stuffing out of me a little bit and I was very disappointed not to able to visit. I could have visited the Bluff as well but, for me, it wasn’t time yet.

So, at short notice, I called Mark to see if he was up for a trip to Quarry 4 on the same day that I would have headed south. Luckily for me, he was and we met up on the Sunday morning at 9AM ready for the hunt. Yet again you could see that another big section of clay had been removed and we walked briskly, eager to start prospecting.

As we approached the back of the quarry, the shell/reptile beds were fully exposed and there were great masses of concretions that were showing on the surface. About thirty yards from the back of the quarry, a long spoil heap had been drawn up by the excavators and this, unusually, was not contaminated by old bricks and there was plenty of new clay to look over. I would save this section for later.

We both began with the ancient sea floor, carefully walking, looking at the nodules and every exposed sections of clay in between. There were two or three really big belemnites that had, unfortunately, been crushed by the excavators and a few Gryphaea of unusually large size fully exposed on the surface but these were ignored. Bigger prey was the order of the day.

After a while, Mark brought to my attention a nodule that had obviously had something entombed within. Careful scraping with picks and brushes revealed the remains of a fish in the block. We could clearly make some spines, presumably part of the dorsal fin, an operculum, a tooth and lots of other bits and pieces. Neither of us are heavily into fish and the exposed remains were obviously too fragmentary to even guess at identification.

Image courtesy of Mark Graham © 2010
But the block was certainly a prime candidate for preparation and it was obvious that the block contained a lot more unexposed bone and looked certain to be a good specimen. We decided to take the block out and first of all consolidated the exposed bone and then proceeded to remove the clay from around the block and leave the concretion sitting proud of the surface. We then attempted to split the block at an appropriate spot. Easier said than done.

For future reference, let me tell you that concretions are very aptly named and, despite the use of extreme force with a variety of chisels and hammers, could hardly make inroads into it. Time was obviously an issue and it became apparent that we were hardly well equipped for this sort of excavation. I think we both understood a little more now and the reasons why concretions with bones in are often taken out whole. There appears to be no other option.

Mark decided to call Cliff Nicklin and see if the museum would be interested in the fish. Cliff agreed to arrange an inspection of the block and then the matter would be taken from there. Satisfied that we had done all that we could, we decided to move on and continued to prospect.

We carefully moved on and arrived at the previously cleared bed. Again, despite our keenest attentions we were coming up short. We took a break for lunch and then headed back to area where the fish was. Mark continued to scour the area and I, reverting to type, started at the beginning of the spoil heap and slowly moved along, often sitting in the middle of the heap and looking very closely.

As I looked into the clay I saw what I thought was a dead slug and immediately thought it was strange to find a slug hundreds of yards away from any vegetation and in the middle of a barren clay quarry. I went to poke it to see if it was dead and was surprised that it was rock solid! As I lifted it up I could see that it was distinctly marked and as I cleaned it off realised that I had a crushing tooth from a hybodont shark.

It was big at over 50mm in length and I later identified it as Asteracanthus ornatissimus. This was a really rare tooth and big – I was absolutely delighted. The preservation and markings on the tooth were beautiful. After showing Mark my prize I carried on surveying this very same spoil for more fossils. I wasn’t to be disappointed.


Astonishing detail in this close-up

Cliff has always said to me that, because everything in sight is clay grey, you have to look for shapes and I have been trying to tune in for some time now. I also knew that a lot of my better finds over the years have been when I get on my hands and knees and look at the sediment really closely. This combination of shapes and close up work was about to pay dividends.

I worked my way along the spoil heap slowly but surely. After about 20 yards I virtually laid my head on the side of the spoil and looked along its length. About 5 yards away I made out a distinct concave shape in the spoil that was obviously out of place, and, as I approached it, I knew what I was seeing. Sure enough, standing proud in the middle of the spoil, was a huge vertebra. It even had a large proportion of the processes intact, despite being rolled about goodness knows how many times by the excavators.


Spot the vert!

I was absolutely delighted. After all the blank trips, all the miles I’d driven and the steep learning curve at Quarry 4, here was my reward. The vertebra was massive and obviously from a very large pliosaur. Not only were the processes preserved but a section of rib had become detached and stuck to the centrum during fossilisation. Again I called Mark to show him my prize and then I wrapped my prize carefully and carefully placed it into the rucksack. We both scoured the immediate surroundings to see if there were any more remains to be found but nothing turned up.

As the day approached its end, it was good that we were, at last, coming to terms with the quarry. We carried on prospecting in the general area of the spoil heap but to no avail. Nothing else was found but that was to be expected and, in the circumstances, I didn’t want to appear greedy!

As we left the quarry, I was to return a couple of times later in 2009 but nothing of note was recovered. We also received word at this time that Quarry 4 was finally going to be closed during 2010 and was to be flooded and turned into a nature sanctuary. This was sad but it did mean that Quarry 5 was finally going to be opened and, as Winter approached, machinery was slowly being transferred to the new site.

Preliminary excavations begun and many tons of glacial sands and gravels were removed but the drag lines soon reached the clays and excavation began in earnest. At this point there was still one drag line working Quarry 4, although we didn’t know why. The reason why became clear to us during the next few months.

2010 was approaching fast and there were changes ahead but we all looked forward to the New Year but first we had the ravages of one of the worst winters in years to contend with.

Wednesday, 8 December 2010

Complex Dinosaurs

Sauropods were a group of large plant eating saurischian dinosaurs found all over the world. For some time now I’ve always thought that when you could solve the biomechanics of sauropods, you could more or less solve the secrets of the dinosauria as a whole. Sauropods were amazing animals.

The functional morphology of sauropods has long come under intense scientific scrutiny. For example, how did sauropods eat enough food to maintain a constant metabolism and support their enormous body sizes? The size of a sauropods’ mouth appears, on the face of it, not large enough to eat sufficient plant matter. This is particularly fascinating when you consider the small size of the head in relation to the body and the relatively poor chewing mechanisms of some (but not all) sauropods (Christiansen 2000; Upchurch & Barrett 2000).

The long necks of sauropods are under continual scrutiny and have been since they were first discovered. There have been all sorts of theories regarding their posture, range, and movement and we are still unsure (Martin et al 1998; Stevens & Parrish 1999; Taylor et al 2009). Were their necks curved? Did they raise them vertically, hold them horizontally, were they sloping down?


Then how on earth did they pump enough blood to the brain and back again? The distances are enormous – in the case of Barosaurus, the neck is approximately 25 feet long, in Seismosaurus, even longer (Choy & Altman 1992; McIntosh 2005). Just how did they manage this? Obviously they did since the giraffe-like Brachiosaurus and Giraffatitan held their necks aloft and must have fed in the tree tops. The engineering required to achieve such blood flow defies belief. Theories are legion but none are universally agreed on.

The reason I mention the issues above is that I think we sometimes lose sight of what nature is capable of. We are all very astute in being able to say what is not physically or physiologically possible and yet we find it difficult to provide any suitable hypotheses or alternatives – at least any that can be agreed on. Totally understandable of course and yet this somehow misses the point.

These animals diversified and radiated for millions of years and were extremely successful. Sauropods did exist in vast numbers; they did eat enough to, not only survive, but proliferate. They did have a cardiovascular system more than capable of pumping blood around their bodies. These animals were truly natural wonders – these dinosaurs were complex creatures.

It was while studying the premaxillae of tyrannosaurs that it really occurred to me how complex they were – indeed how complex all theropods are, both avian and non-avian. If we concentrate on tyrannosaurs, however, we can see what has happened over the years. Certainly, despite vast amounts of data to the contrary, these animals are sometimes portrayed as slow scavengers who were not even capable of staying on their own two feet unless they stood still. This is just plain wrong.

Naturally enough, mention tyrannosaurs and it is Tyrannosaurus that comes to the fore and rightly so. For me this has to be the single most impressive land predator ever and it is understandable that huge amounts of study are devoted to this species. After all, the amount of material recovered in the last twenty years is astounding – over forty known specimens and the numbers are rising (Larson 2008).

Back to tyrannosaurid premaxillae then. Tyrannosaurus is continually portrayed as a huge bone shattering, crunching set of jaws that was able to consume vast amounts of flesh and bone in huge gulps. Perfectly reasonable – there are even coprolites full of pulverised bone (Chin et al 1998). Except that tyrannosaurs also had an arcade of eight premaxillary teeth (Holtz 2004). What were they for?

A typical D-shaped tyrannosaurid premaxillary tooth.

Maybe they were used for grooming, intraspecific communication or, as seems to be the general consensus, these teeth were used for selective feeding (Hone & Watabe 2010), stripping flesh from the bone and nibbling bits of flesh off, maybe, to even feed their young . Either way, this immediately does away with the common depiction of Tyrannosaurus as a simplistic bone-mashing-eat-everything carnivore. If Tyrannosaurus just fed like this then why have a premaxillary? The premaxillary suggests complex behavioural patterns – otherwise why bother with it?

And then when you start to look at tyrannosaurs in more detail, their general biomechanics, just like sauropods, are astounding. The overall combination of good eyesight, superb sense of smell and hearing is generally accepted and the brain was relatively large to process all the details (Witmer & Ridgely 2009). These are adaption’s, not only for hunting and scavenging, but for intraspecific communication and environmental awareness.

Another adaption to consider is bipedalism – the general body plan for all theropods is more or less the same, pot-bellied therizinosaurs not withstanding. High running speed in tyrannosaurs has come under intense scrutiny over recent years and whilst it is generally accepted that a top speed of 40mph is somewhat exaggerated, a 40 foot long, 7 ton tyrannosaur running at 15 mph is not exactly hanging about and was more than adequate to run down its contemporaries (Farlow et al 1995b; Paul 1998).

However, even a tyrannosaur briskly walking has come in for some tough scrutiny. It has been suggested that a tyrannosaur would hardly dare break into a trot just in case it tripped or fell. I mean what would a theropod do if it broke a leg or, as has been suggested, couldn’t even get back to its feet and remained grounded?

Whilst this may have an element of mechanical soundness about it, the truth actually stares us in the face. Let’s take a couple of steps back and think about it. An entire clade of dinosaurs, the theropoda, evolved into bipedal animals that walked on their toes and endured for around 150 million years – considerably more if you include aves. These animals ranged in size from critters the size of a chicken to huge multi-tonne mega-carnivores. If these animals were continually falling over, breaking bones, and not able to get up then evolution would have demanded a change in their way of moving around the terrain or theropods would have probably become extinct within a very short time span. After all, ostriches don’t worry too much about whether they will trip and fall when it is time to outrun a predator – albeit an ostrich doesn’t weigh a few tons.

I’m being a little simplistic here but the point is essentially correct. Theropods did not worry about falling over and did not hesitate to put their foot on the gas when food was required. And again the ability to combine agility, judgement and hunting skills is indicative of complex animals.

Finally, a look at the tail of a tyrannosaur. The tail was a massive part of the animal, held proud from the ground, heavily muscled and not only acted as a counter balance for the large head of the animal, but was also the driving force that propelled the animal forward at speed and would have been vital in maintaining equilibrium when the animal moved. And, indeed, while writing this post, a newly published paper (Persons & Currie 2010) makes a point of this very issue and puts some substance behind the theory.

This combination of characters, from the massive head through to the tail, and all of the specialised traits in between suggests a level of complexity comparable with any extant mammal of today. Behavioural inference can only be that – inferred but that still leaves an enormous amount of physical evidence that is totally indicative of complexity within species.

Dinosaurs were complex animals of the highest order. Of that there is and should be no doubt.


Referances

Chin, K., Tokaryk, T.T., Erickson, G.M., Calk, L.C., 1998. A king-sized theropod coprolite. Nature 393, 680–682.

Choy, D. S. J. & Altman, P. 1992 The cardiovascular system of Barosaurus: an educated guess. Lancet 340, 534-536.

Christiansen, P. 2000. Feeding mechanisms of the sauropod dinosaurs Brachiosaurus,Camarasaurus, Diplodocus and Dicraeosaurus. Historical Biology 14, 137–152.

Farlow, J. O, M. B. Smith, and J. M. Robinson. 1995b. Body mass, bone “strength indicator,” and cursorial potential of Tyrannosaurus rex. Journal of Vertebrate Paleontology, 15:713–725.

Holtz, T. R., Jr. 2004. Tyrannosauroidea; pp. 111–136 in D. B. Weishampel, P. Dodson, and H. Osmolska (eds.), The Dinosauria, second edition. University of California Press, Berkeley, California.

Hone, D.W.E., and Watabe, M. 2010. New information on scavenging and selective feeding behaviour of tyrannosaurs. Acta Palaeontologica Polonica 55 (4) 627-634.

Larson, N 2008. One Hundred Years of Tyrannosaurus rex: The skeletons: pp. 1-55 in P. Larson and K. Carpenter (eds.), Tyrannosaurus rex, the Tyrant King, Indiana University Press, Bloomington, Indiana

Martin, J., Martin−Rolland, V., and Frey, E. 1998. Not cranes or masts, but beams: the biomechanics of sauropod necks. Oryctos 1: 113–120.

McIntosh, J. S. 2005. The genus Barosaurus Marsh (Sauropoda, Diplodocidae). In Tidwell, V. & Carpenter, K. (eds) Thunder-Lizards: The Sauropodomorph Dinosaurs. Indiana University Press (Bloomington & Indianapolis), pp. 38-77.

Paul, G.S.1998. Limb design, function and running performance in ostrich-mimics and tyrannosaurs. Gaia 15:257–270.

W. Scott Persons, Philip J. Currie 2010. The Tail of Tyrannosaurus: Reassessing the Size and Locomotive Importance of the M. caudofemoralis in Non-Avian Theropods. The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology, 2010.

Stevens, K. A. & Parrish, J. M. 1999 Neck posture and feeding habits of two Jurassic sauropod dinosaurs. Science 284, 798-800.

Taylor, M. P., Wedel, M. J. & Naish, D. 2009. Head and neck posture in sauropod dinosaurs inferred from extant animals. Acta Palaeontologica Polonica 54, 213-220

Upchurch, P. and Barrett, P. M. 2000. The evolution of sauropod feeding mechanisms. pp. 79–122 in Sues, H.D. (ed.): The evolution of herbivory in terrestrial vertebrates. Perspectives from the fossil record. Cambridge University Press.

Witmer, L.M. and R.C. Ridgely. 2009. New insights into the brain, braincase, and ear region of tyrannosaurs, with implications for sensory organization and behavior. Anatomical Record 292:1266–1296.

Wednesday, 1 December 2010

The Ammonite Macrocephalites



This is the Middle Jurassic ammonite Macrocephalites – from the Early Callovian of Lincolnshire and collected at the end of the 19th century. I was given the specimen by a friend of mine, Maria, who was given a private collection from a client of hers (Maria is a hair stylist).

The clients’ mother had recently died and, during the house clearance, there was a coal scuttle that was filled with fossils and minerals. Knowing that Maria had a liking for curios, she gave the collection to her and Maria asked me to pop around one evening and help identify some of the pieces.

The collection is delightful – somebody’s very personal accumulation of finds over the years and, although there was not too much that was either very well preserved or of any significance, there were some interesting pieces.

There were ammonites, belemnites, brachiopods, sponges, corals, echinoids and some plant fossils, as well as few bits that were, although organic, hard to identify. The minerals I couldn’t particularly help with (not my field I’m afraid). There was also a couple of deer antlers, probably Pleistocene in origin, and the most unusual piece was a section of swordfish rostrum, but this was not fossilised and was obviously contemporary.

Maria gave me the ammonite as a thank you, which was nice of her, and said that the collection would be donated to a local school or museum which is just great. The label in the second picture is delightfully written and says, if you can’t make it out, “Ammonite, from Swinstead, Lincolnshire, July 1897”. It’ll take a little prep work to clean it up but it is a really nice example and, considering the collection date, a historical piece. Thanks Maria!

Wednesday, 24 November 2010

Book Review - Dinosaur Odyssey

Scott Sampson is one of the most popular and respected palaeontologists’ of the modern era. Major contributions to the science for many years now always demand the highest respect from his peers and graduate students alike. He has also been a familiar face on television and his Dinosaur Train has been very well received stateside where it is aimed at a younger audience, no doubt joined by their equally interested parents!

Meeting Scott was an equally pleasurable experience and I found him to be an extremely pleasant man, easy going and willing to exchange many views and ideas with me. It was equally apparent that he is a driven palaeontologist with an ever increasing thirst for more knowledge. His passion is quite infectious.

Dinosaur Odyssey has been described as the first general-audience book on dinosaurs for many many years. Having said that, I believe it does help to have a general understanding of palaeontology although anybody with an interest in the natural world or earth sciences will enjoy it.

The premise of the book, as opposed to the usual encyclopaedic style of dinosaur books, is to entice the reader and draw them into the bigger picture – the web of life, as mentioned in the title. Instead of concentrating on specific individual genera or species, the reader is invited into this bigger world and specifically how dinosaurs were part of it and especially how they were, in relative terms, a small component in the vast ecological processes that took place throughout the Mesozoic.

This does not mean that dinosaurs are not covered in any detail – they most certainly are – but we are always reminded that they were part of a much bigger picture. I cannot think of another book that brings the world of the dinosaurs to life in so much detail. From sun light and water to microbes and soil formation, right through to the carnivores at the top of the food chain, through to death and back again, we can see how the world of the dinosaurs was formed by the same processes that affect our world of today.

There are up to date details concerning all the major groups of dinosaur whether herbivore or carnivore and there is an excellent chapter concentrating on ornithischians and ceratopsians. The horned dinosaurs are a passion of Scott’s and he describes in detail how horns and frills were almost certainly evolved for sexual selection and both species recognition and interaction.

The physiology of the dinosaurs is discussed – specifically whether they were endothermic, as in birds, or ectothermic like crocodiles. In fact Scott describes them as mesothermic by using a theory he refers to as the Goldilocks hypothesis. In other words, not hot, not cold but rather something in between. His arguments make good reading but, of course, this will need to be backed up in the literature, although this theory is very much in fashion just now. Personally, I like to believe they were fully endothermic animals but this argument could fill volumes on its own and certainly not for this review.

How dinosaurs became masters of the planet is also covered and once again the combination of so many different but interlinked factors describes their rise to prominence. Scott also goes in to great detail to debunk the possibility of there ever being a Jurassic Park and this makes good reading because it takes someone like Scott to highlight the multitude of obstacles that would exist in simply being able to maintain these animals, let alone creating them in the first place!

Dinosaur provincialism has been in the literature over the last few years and again is another subject that Scott has investigated in some detail. Indeed, the North American continent, that was split into two by the Western Interior Seaway during the late Cretaceous, is throwing up so many questions with regards to just how many different species of big animal managed to live at the same time in what appear to be small pockets of land on a relatively small land mass (Laramidia). This is probably a subject worthy of a symposium in its own right.

Other chapters feature the authors work in Madagascar and the other inevitable chapters on dinosaurs becoming birds, and their extinction at the end of the Cretaceous, completing the volume. The book is interspersed with both colour and black and white images and I particularly like the pencil illustrations at the beginning of each chapter.

Dinosaur Odyssey represents a new kind of dinosaur book. It could almost be written for ecologists and naturalists of today, and this is the secret of the book. This is nothing new, and so many people have said it in the past, but to tackle the issues of today we need to refer to the issues of the past and I know of no other book that makes you search for your place in the bigger picture that is today’s web of life. I would urge you to read this volume because it contains so many relevant and important messages. Highly recommended.

Wednesday, 17 November 2010

Return to the Devil's Hole


In June I was able to return to the Devil’s Hole, almost two years since my last visit. Mark couldn’t make this trip but I expected to see plenty of people that I knew from previous. Again the weather conditions were favourable and I was hopeful of a good day.

On arrival at site we had to sign in and also sign a disclaimer. I noted that the security this time was even more intense and we only had a four hour window in which to prospect. We were told that there had been significant working in progress and that there would be plenty of terrain to scour.

They weren’t wrong either. On this occasion, we were allowed to drive almost to quarry side, which helped, and from the cars you could see the vast expanse of excavation that had taken place. Ahead you could see piles of sand and gravel spoil intermingled with exposures of Oxford Clay. Gullies, filled with water, carved channels throughout. There was plenty of room for everyone and we made our way in full of anticipation.

There was so much to look at that it was obvious that it really didn’t matter where to start but a couple of us started parallel to one of the ditches and started to look at some clay exposures. There were already some ammonite partials exposed and it was obvious that there would be some good finds today.

I crossed the ditch where it narrowed and looked among some spoil heaps. I soon found what were obviously a couple of bovine teeth on the surface. I gathered them together with all the loose pieces of enamel and placed them in a specimen bag. Closer examination revealed them to be a couple of woolly rhinoceros teeth - a good find.

I pushed on trying to get a balance between careful prospecting, along with covering as much ground as possible – not easy. Too fast and you risk missing something, too slow and you simply do not cover as much ground as you would like to. I convinced myself not to worry since there was so much ground to cover that it probably didn’t matter.

After a while I spotted one of the others whom I had met before on several occasions. He’s very good at maximising his time in these Pleistocene quarries. I’ve watched him and as soon as you can get in the quarry he moves very quickly and walks on the spoil heaps looking for the big bones that are exposed.

Well he had a red letter day finding a big partial femur which some reckon is mammoth. I don’t – I think it’s too small unless it’s a juvenile but then mammals are not a speciality of mine. He also found a rhino humerus (lovely bone), a wolf bone and some other bone as well.

All of these bones were found in the first hour! I reckon he covered the majority of the site in an hour and a half while the rest of us had worked on just the one side. Fair play to him though – that way of prospecting certainly works for him. But I think he probably misses some important material that way.

I pushed on and decided to take a circular route around the quarry, ending up where I started. This would miss an awful lot of ground out but, as mentioned earlier, that would still leave me plenty of acreage and we were constrained by time. I also decided to vary my search pattern by covering sections of spoil heaps and sections of gullies. This was a lot of leg work but I felt it gave me the best chance of finding more material.

As it turned out, and not for the first time, I was wrong and could not find anything else. As I headed back to my starting point I bumped into one or two others who had also found a rhino tooth, bigger than mine but not as well preserved, and some excellent ammonites. I decided to drop down to the Oxford clay to see if I could find any ammonites for myself.


I actually managed to take myself out onto a peninsula and found myself surrounded by water which meant I had to walk all the way back and circumnavigate that section to get back. I passed Carl along the way, and told him what lay ahead, but he decided to look anyway. Carl had already recovered some bone fragments, nothing brilliant, but nice pieces.

I walked back to the area where I found the rhino teeth and decided to thoroughly scour the area and see if there were any more to be found. There wasn’t and our time was nearly up. I eventually caught up with Carl and was pleased that he had recovered a few nice ammonites, but not so pleased that he had recovered them from the peninsula and that I had obviously missed them. Oh well, such is life.

As we strolled back to the cars it was obvious that most people had some good finds. Apart from the fore mentioned bones there were plenty of ammonites found that were topped by one huge specimen, at least, I6 inches across. All in all it was a pretty good trip but the time constraint was frustrating. But I can’t complain and I can see a time when this quarry will be closed to collectors – I just hope that it won’t be any time soon.

Footnote
After leaving the quarry Carl and I decided to have a spot of lunch in a lay-by just up the road. I asked Carl what he did for a living – a molecular scientist! I’m impressed – he said that he would have liked to do palaeontology for a career but that there are even less openings in that discipline than the one he eventually chose. I think he made the right choice.

As you may remember from previous entries, the Devil’s Hole remains closed just now but both it and Minnie’s Quarry should reopen next year. Considering that earlier this year the outlook for both quarries was bleak, this is indeed good news and I’ll keep you informed of developments.


The above image shows the recovered rhinoceros teeth after preperation and consolidation. Nice example.

Tuesday, 9 November 2010

Alan Dawn 1923 - 2010

Coincidence has a strange, and sometimes unfortunate, way of materialising in life. It was only recently that I published a couple of posts as an introduction to the Oxford Clay and it is no surprise that the name of Alan Dawn was mentioned more than a few times. Sadly, if you didn’t know, Alan passed away on October 31st after a short illness. He was 87.

Alan was an amazing man and truly one of the great amateur paleontologists of his or, indeed, any generation. Although he worked on and prepared Pleistocene mammals, his legacy is his work on the marine reptile fauna from the local clay quarries in and around Peterborough.

As an avocational paleontologist and preparator myself I can truly admire his dedication and achievements and his contribution to our understanding and perception of the Oxford Clay fauna simply cannot be underestimated.
I could write a few other things about Alan’s life but his friend Jeff Liston has done a much better job at it than I could and has written a nice tribute page at his website here.

Alan lost his wife Pauline only recently and will be greatly missed by family and friends alike and we all send them our sympathy and condolences.

One of the true greats of recent times in British paleontology and is a sad loss to all of us who knew him.

Thursday, 4 November 2010

Getting Closer.....


In May we returned to Quarry 4. Conditions were good and the forecast was for a cloudy day with sunny intervals. Temperatures were in the low teens and we both felt that today would be a good day.

As we walked toward the far side of the quarry it was apparent that enormous amounts of clay had been removed. It never ceases to amaze me that the Bluff remains closed because of the economic climate and yet Quarry 4 continues to be worked hard despite the downturn.

We dropped to the quarry floor and began to prospect. It wasn’t until we got closer to the newly quarried face that we realised the full extent of the clay removal. I was amazed - it must have amounted to hundreds of tons of spoil that had been taken out. Still, it gave us a large area of virgin territory to search for fossils.

Better still, nearly all the flood waters had now receded and so we could search the areas that had been under water for some months. We looked in earnest, keen for success since I think we are both of the opinion that we are not the luckiest prospectors’ and almost resigned to the fact that the next person who follows us in will find the next plesiosaur or ichthyosaur.

Similarly to last time it was hard going. There were some areas that were particularly rich in belemnites and Gryphaea but, as mentioned before, this was zonal. There wasn’t a great deal of wood either and we knew early on that we would struggle. And yet everything felt right and we knew that we were going to persevere and eventually I found a small piece of bone. Not the most impressive piece you will ever see but at least it was a start.

Not too far from the spot where we had started to prospect, I began to look on the quarry floor that ran parallel to a long spoil heap. Where it ended there was a narrow gap before the next spoil heap began. I walked through this and double backed on myself walking on the other side of the spoil.

After a few yards I managed to spot a small piece of bone that was exposed on the surface. A good gust of wind would have probably covered it over with dust again but at last I got lucky. It was very narrow and rib-like and I gently began to uncover it. Slowly but surely, a delightfully preserved rib materialised. It was gently curved and virtually complete although it was fractured in a few spots.


I called Mark over and he recommended that we separate the clay from its surrounding matrix and remove it whole. I cleaned off the exposed bone, stabilised it with consolidant, and slowly began to separate the bone supporting block. After slow but sure progress the support block fractured and the lower part of the rib broke away but this wasn’t a problem and the remainder was removed intact. The two blocks were then carefully wrapped up and packed and I was ready to continue the search.

I searched the immediate area for quite a while to see if the bone was an isolated element or whether there was any more of the animal to be found but this was not to be the case, unless there was more remains under the spoil heap but it seemed unlikely. Satisfied that there was nothing left to find, I moved off in search of other material elsewhere and to join up with Mark who was now a little ahead of me.

Eventually we approached the bed where we spent so much time searching last time and soon my eyes focussed on a very familiar area. Sure enough we came across our rock markers which marked the spot where our tree trunk was located from our previous trip. We were both a little saddened to see that the trunk was still in situ but now much worse for wear and disintegrating.

Although a little aggrieved by this, I suppose it is a little understandable. Where do you store such a trunk as this? And the conserving problems are immense. I suppose in reflection that, although it was impressive, it was not particularly well preserved, there was no bark remaining, and all that was left was this huge chunk of carbonised wood.

Well we did the right thing in reporting the find. Now it will very soon crumble to dust and disappear forever but it was impressive when we found it and I have a good photographic record for posterity. We continued to search and, as mentioned previously, were now able to look in the areas that were now dry but still we could find nothing else.

One thing that we may take next time are yard brooms! When the clay is dry and dusty, the shiny enamel of fossil bone can be hidden and, although half joking about this last time, I am starting to believe that there may be some merit to the idea and that a quick sweep of a broom may help in uncovering bone that may be otherwise missed. We’ll see.

We made our way out of the area, and began to go over old trenches and the gullies that we had scoured previously but, again there was nothing more to be found and we decided to call it a day. As usual, we took the long way back to the cars in the hope of falling onto something, but it wasn’t to be.

Quarry 4 leaves me feeling a sense of inevitability that our time will surely come and that as long as we persist then we will find our skeleton. It’s a different feeling from the Bluff, which is a place that compels me to go regardless. Although skeletons have been removed from the Bluff they are incredibly rare, three that I know of, maybe four, so you know that you would normally be looking for isolated bone elements.

But Quarry 4 and the surrounding area have produced an abundance of skeletons over the years and as long as the clay is here and bricks are required, then there will be many more finds to come. I just hope that we are here for the next few skeletons that are found.

Footnote

For a look at the prepared rib, see here.

As mentioned in previous posts, Quarry 5 is now being worked quite heavily and, if all goes well, we will have access early next year. Quarry 4 is still down to be flooded very soon but there is no agreed date for this and we continue to have access until January 2011 although there are no new excavations and we are relying on the elements to uncover anything.

A further quarry, not too far away, has also been earmarked for extraction in the future and would be a massive excavation, so the future for more marine reptiles being found appears extremely positive.

Monday, 1 November 2010

Tyrannosaurs + Preparation = Utopia!

When someone blogs about tyrannosaurs, I am drawn to it like a moth to a flame. Similarly, blogging about prep work, which is another huge interest of mine, has myself reading it so that I can soak up every last morsel of information. When someone blogs about preparing a tyrannosaur I am in heaven!

If you are unaware, let me point you in the direction of Dave Hone’s Archosaur Musings. Dave has often run a series of guest posts or interesting interviews with many figures in the world of palaeontology but his latest addition is a real coup, especially for tyrannosaur aficionados’ such as myself.

Darren Tanke is senior technician at the Royal Tyrrel Museum of Palaeontology and, back at the end of the 2008 field season in Dinosaur Provincial Park, located the bones of a juvenile Gorgosaurus. Juvenile dinosaurs are a rare find for any species but especially so in theropods, so this was an important specimen.

The block containing the bones was eventually lifted out earlier this year and Darren is actually preparing the specimen now at time of writing. Darren has agreed to give a series of updates over the upcoming months giving us an inside view into the world of the preparator and, at the same time, uncovering one of the coolest dinosaurs ever to walk the planet!

Not only will you find this amazing story unfolding on the Musings but the Tyrell’s own Facebook page is also covering the story. I implore you to follow this story as it unfolds since this is probably the first time a specimen of this importance has been prepared and uncovered as it happens. Well done Darren for letting us in and to Dave for bringing it to the paleo-blogosphere!

Wednesday, 27 October 2010

An Introduction to the Oxford Clay - Part 2

In the first part of this mini-series, we looked at how the Oxford Clay was deposited and took an overview of the general climate, palaeoecology, and fauna of this highly complex ecosystem. Now I am going to look at some of the more important marine reptiles that have been recovered from this very important rock unit.

For more than 100 years now, the brick-making industry has given us a unique insight into the ancient Jurassic seas. The mud and sediment that accumulated on the sea floor formed the Oxford Clay, and this has been extracted from the brick pits on a massive scale which, in turn, has revealed a myriad of saurian remains.

In England, the area in and around Peterborough has proven to be a rich source. Alfred and Charles Leeds were probably the most significant of the early collectors. The Leeds brothers gathered, en masse, an extensive collection in the early 1900’s and these form the backbone of the marine reptile collections at both the British Museum of Natural History and the Hunterian Museum in Glasgow.

John Phillips was another important collector during the 1920’s and some of his finds reside at the Peterborough City Museum & Art Gallery, as do the more recent discoveries made by Alan Dawn during the 80’s and 90’s. Bedford, Aylesbury and St.Ives in Cambridgeshire are all museums that also hold small collections of Oxford Clay vertebrates.

Also worthy of mention are the substantial collections held at the University of Leicester, which was placed in the repository by both David Martill and Roy Clements, and in the National Museum of Ireland (see Araujo et al 2008).


There are several superb specimens of international significance in the Peterborough collection and these are on permanent display at the Priestgate venue. Amongst these is a virtually complete specimen of the marine crocodile Steneosaurus durobrivensis, more correctly termed a thalattosuchian. This was recovered by Phillips in 1923 and is displayed three dimensionally.

Dogsthorpe Quarry was one of the better known Oxford Clay quarries and during its time was extremely prolific. A more or less complete specimen of Cryptoclidus eurymerus was extracted from Dogsthorpe back in 1984 by Alan Dawn and a group of volunteers from the museum. The skull of this specimen is regarded at the best preserved and most complete ever found.


Even when Dogsthorpe was finished as a clay producing quarry and was being turned into a waste landfill site, it still produced the odd surprise. An employee of Shanks and McEwan, the company who managed the site at the time, discovered the magnificent pliosaur that is Simolestes vorax. This too was excavated by Dawn along with Gordon Chancellor, the then curator at Peterborough Museum. This specimen was virtually complete and well preserved, especially the unique skull which eventually featured as one of the subjects in Dr Leslie Noe’s Phd thesis on Callovian plesiosaurs (2001).

King’s Dyke was another well known and productive quarry. In 1994, yet another new genus of pliosaur was discovered, once more by Alan Dawn. Again largely complete, the skull and cervical vertebrae were almost perfectly articulated and undisturbed, although the rest of the post crania was not. This was the holtype of Pachycostasaurus dawnii and provided yet more new data on plesiosaurian evolution.

Another quarry in the vicinity was Star Quarry, one that I have visited on one occasion and was only flooded last year and is now inaccessible. In 1996 this quarry produced a magnificent, virtually complete specimen of Opthalmosaurus icenicus. This was unusual in as much as the ichthyosaur was recovered from the Middle Oxford Clay (Stewartby Member), much like a previous specimen from King’s Dyke, although this was a far superior example. Originally found by an amateur collector, Nigel Truss, this specimen is also on display in the Peterborough Museum.

Star Pit became the subject of nationwide interest during 2001 when students from Portsmouth University found the remains of the giant fish Leedsichthys problematicus. Estimated at the time to be almost 100 feet long, it is now generally believed to a more conservative, although still massive, 30 feet long.

Once funding had been obtained, Dave Martill, Leslie Noe, Jeff Liston, Darren Naish and students, along with local volunteers from a local geological society began the excavation. Some of this was broadcast nationwide on Channel 4 via their mini-series The Big Monster Dig during 2003.

So it can be seen that not only have these clay quarries had an extremely important social and economic influence in the local area but also gave us a window through time, back to the primordial Jurassic seas. Most exciting of all, as can be seen by the discovery of Pachycostasaurus, there is still so much we don’t know and still discoveries to be made.


There may not be the amount of quarries remaining now but the odd few that remain will continue to produce and it is important that any new discoveries of scientific importance are protected and deposited into the correct repository for both study and for future generations.

Referances

A.R.I. Cruickshank, D.M. Martill and L.F. Noè A pliosaur (Reptilia, Sauropterygia) exhibiting pachyostosis from the Middle Jurassic of England
Journal of the Geological Society.1996; 153: 873-879

Andrews CW. 1913. A descriptive catalogue of the marine reptiles of the Oxford Clay, Part Two. London: British Museum (Natural History) 206pp.

Araujo, R; Smith, A.S. and Liston, J. 2008. The Alfred Leeds fossil vertebrate collection of the National Museum of Ireland - Natural History. Irish Journal of Earth Science, 26, 17-32.

Dawn, A. 1997. Fossil marine reptiles of the Peterborough brick pits. Mercian Geologist, 14, (2), 90-93.

Geoffroy Saint-Hilaire, É. 1825 Recherches sur l’organisation des Gavials, sur leurs affinités naturelles desquelles résulte la nécessité d’une autre distribution générique. Gavialis, Teleosaurus, Steneosaurus. Mémoires du Muséum Histoire
Naturelle 12, 97–155.

Liston, J. 2004. An overview of the pachycormiform Leedsichthys. In Arratia, G. & Tintori, A. (eds) Mesozoic Fishes 3 - Systematics, Paleoenvironments and Biodiversity. Verlag Dr. Friedrich Pfeil (München), pp. 379-390.

Lydekker, R. (1889) Catalogue of the Fossil Reptilia and Amphibia in the British Museum, Part II; Containing the Orders Ichthyopterygia and Sauropterygia. British Museum (Natural History), London, 307 pp.

Martill, D. M. (10) Marine Reptiles. In Martill, D. M. & Hudson, J. D. (eds) Fossils of the Oxford Clay. The Palaeontological Association (London), pp. 226-243.

Noè, L.F. A taxanomic and functional study of the Callovian (Middle Jurassic) Plesiosauroidea (Reptilia, Sauropterygia). Ph.D thesis, University of Derby, Derby. UK

Phillips, J. 1871 The geology of Oxford and the valley of the Thames. Oxford. Clarendon Press.

Seeley, H.G. 1874b On the pectoral arch and forelimb of Ophthalmosaurus, a new ichthyosaurian genus from the Oxford Clay. Quarterly Journal of the Geological Society of London 30,696–707.


Image shows a recently recovered Leedsichthys rib from Quarry 4.

Thursday, 21 October 2010

First Life

Sir David Attenborough, at the age of 84, still shows no sign of slowing up or retiring. And I'm pleased to say that his next mini-series, First Life, will be airing on the BBC during November.

Any series made by Sir David is always eagerly awaited but this is a welcome return to a palaeo-themed programme, which is something that has always been close to his heart and is his first series of its type since Lost Worlds, Vanished Lives which I consider to be amongst the best of any general audience palaeontological series, along with Alan Charig's Before the Ark (which I would love to see again).

First Life focuses on the very origins of life and both examines and compares fossils with descendant and extant living relatives. Sir David travels the world on a journey of discovery, meeting palaeontologists' along the way who reveal the latest techniques utilised to help uncover the secrets of the origin of life.

I'm not too sure when this will air over the pond but I'm hopeful that you may be able to view it on BBC I-player. Incidentally, Sir David is also making a special on pterosaurs called Flying Monsters 3D to be shown on Sky's new 3D channel in the not too distant future.

Thursday, 14 October 2010

SVP 2010 - A Brief Review

Now that the 70th SVP meeting in Pittsburgh has drawn to a close (very successful as well I’m told), I thought I’d mention a few things that came up during the meeting and that I’m looking forward to hearing more about in the coming weeks and months.

This year’s abstracts were full of goodies covering a wide range of subjects but there were some highlights. Starting off with the in vogue ceratopsians and there was yet more on the morphology, ontogeny and homology of these totally fascinating dinosaurs. And yet still more, as well, on Triceratops and, yes, Torosaurus – things keep rumbling on.

Certainly synonymy and, the latest buzz-word, anagenesis featured highly at this years meeting and there is continuing discussion, at all levels, regarding these very high profile subjects.

Ankylosaurids got some deserved attention this year as did the sauropods which included work on titanosaur evolution and rates of teeth replacement within the group. Hadrosaurs got a bit of attention, again mainly anagenesis and morphological issues and there was an interesting report on a particular edmontosaur bone bed in Wyoming.

I’ve become more interested in micro vertebrate sites during the last year and there were yet more interesting presentations including anthill sampling and other work in the Hell Creek formation. There were also a couple of detailed posters for preparators’ that I’m interested in and the preparators’ session, in general this year, was very well received.

Tyrannosaurids were well represented with detail mainly concerned with ontogeny, evolutionary trends and morphological data as well as some very cool information on their palaeogeographical distribution and what appears to be a couple of new taxa.

Other theropods were well represented including work on a new basal theropod, a new dromaeosaur and ongoing research into abelisaurs. Other bits and pieces included a new pachycephalosaur and some fascinating insight into hypsilophodont feeding techniques.

Not so many presentations on marine reptiles this year although mosasaurs and pliosaurs were represented and there was some detail concerning ichthyosaur extinction. However, the one presentation that fascinated me above all others was about cryptocleidoid plesiosaurs and the fact that there appears to be evidence of a tail fin! I hope to discuss this, and many other issues mentioned above, further in the not too distant future.

Tuesday, 12 October 2010

Misty Bluff - Another First


April 2009 arrived and it was soon time to return to the Bluff. Again it was another trip without any new scrapings so we would be looking over old exposures, but at least there had been another winter of wind, rain and frost to help uncover any new prospective remains.

I arrived early and was disappointed to see a contingent from the Isle of Wight again, but this time there were only four of them. However, the one guy I found so disagreeable from the previous trip was one of them. So be it then. I quickly signed in and made my way to the Bluff.

I still haven’t got used to the fact that it hadn’t changed again. Previously there would always have been a scraping or some form of quarry work that would change at least one of the facies, but not now – not until the quarry is working again.

As usual I dropped onto the south easterly reptile beds and began to prospect. The winter had washed away the previous year’s excavations although you could just make out where they had been. I’d only been looking for a few minutes when the IOW group arrived. I could hear them before I saw them – quiet they aren’t!

They walked around me, shouting away to each other but I was lucky this time and they soon headed toward the far side of the quarry. Once they’d gone, I settled on a plan. After finishing this face I would cross the quarry road and search the same reptile beds that do not get as much attention. Then I would go to my fish spot and search for scales and bone. I refer to it as my spot since I know for a fact that I am the only person to spend any time there.

After this I would scavenge the area where all the bone pieces were recovered the previous autumn. I didn’t want to do that straight away since I was waiting to see if the guy who originally worked the spot was returning to carry on the excavation. Some of us still have scruples!

It was soon apparent that the south east face, despite by no means being worked out, would need some significant work to reveal new material. How we are all hoping the quarry reopens soon! I quickly made my way across the quarry road to the part of this bed that is not scavenged as much.

After a quick preliminary look, nothing of size was apparent so I decided to do some “up close and personal” prospecting, carefully examining the sediment at extreme close range, slowly moving along the face, hoping to catch any visual clues that may lead to a fossil.

It wasn’t long before I came across a cracking little crocodile tooth. Unfortunately it had obviously been exposed for some time and had become a little weather beaten, and almost all of the enamel had been lost. It still retained its shape and striations, however, and I was encouraged by the find.

Only a couple of yards away I found another tooth. This was much smaller and well worn, although it retained a blue hue under the eye glass. It was recurved in shape but the tip was rounded off. It’s difficult to identify and will need further comparison and study under the microscope.

Once I was happy that there was nothing else to be found, I made my way across the bottom of the quarry to the fish beds. As usual there had obviously been no-one prospecting since I was last there, and I expected to find material again. I therefore wasn’t surprised when I found a few lepidotid scales and a rare vertebrae, although not as much as I had expected, especially with a harsh winter behind us.

I sat down for a while and had something to eat and a drink. I looked toward my next destination and was pleased to see the bed devoid of other prospectors. I was soon making my way to the face and to the spot where all the bone had been recovered previously.

Incidentally, it pays to keep a photographic record of all locations for future reference, especially working quarries. Before the Bluff was mothballed, great swathes of clay would be removed between visits and previously worked sites were rendered unrecognisable. A photographic record will at least ensure that you can return to productive areas since, at the very least, you can use land marks on the horizon (as per Currie and his albertosaur bed albeit on a much smaller scale) as the fixing points.

Referring to the photograph I was able to walk right to the bone bearing bed and start looking. I started to locate bone fragments in the spoil heap straight away and recovered more material immediately below the heap. Whilst none of the material was diagnostic in any way, a couple of the better pieces do support the previous assertion that this is rib bone, but from what creature is anyone’s guess.

Satisfied there were no more surface finds to be had, I dug into the bed a little further to see if there was any more material to be uncovered. It was soon apparent that this wasn’t going to be the case so I moved on scouring the same bed for more bone, but nothing was forthcoming. Eventually I headed back to the south east face for another look before finishing for the day.


As I approached the face I became aware of some great excitement at the top of the ridge. On their previous trip here, the IOW group had decided to excavate into a bank that abutted the south eastern reptile beds. They had dug an enormous gulley and made significant inroads into the face. They had found nothing, which didn’t surprise too many people since, even during the years I’ve been coming here, this face has turned up very little. Indeed, the only fossils I saw from here were a big slab of clam shrimps.

This time, after their initial forays onto the Bluff, they decided to carry on with their excavation, only with startling results. After more excavating they began to uncover some excellent dinosaur tracks, a first for the Bluff. They were mainly theropod tracks, although there was one good ornithopod track. These had been removed individually and at the moment it is hard to know if a track way is involved.

For me, this is the Wealden at its best. Classic examples of dinosaurs strolling about on the flood plain and, since this is the type locality for Baryonyx, it’s a nice thought that maybe one or two of these tracks may have been laid down by the very same animal.


What happens now is unclear. It’s tempting to arrange for the removal of the overburden to see if a track way is involved and, at time of writing, neither the funds or inclination are there to proceed in this direction. It may be beneficial to wait for the quarry to reopen since the quarry owners are palaeo-friendly and it should be fairly simple to arrange the removal of the overburden.

Also it will be of benefit to perhaps wait until later in the year when, almost certainly, there will be further manual excavation into this bed. And no matter how many volunteers there are and how strong they may be, the clay is extremely tough and it takes a lot of hard labour to remove the spoil. I don’t believe that this will be detrimental if a track way is involved, but we’ll see.

At this point I should also say a big “well done” to the IOW boys. Despite my earlier criticism of their attitude and overall mannerisms, it has taken them hours of hard work for this reward and they have definitely earned it. So hats off to them, but let’s hope they show some humility now since everyone else congratulated them on their find.

After taking some images of the tracks I said my goodbyes and moved off site, leaving them to continue with their excavation although they were looking tired and I reckoned that they wouldn’t be there for much longer.

The Bluff is unique in the country. I know of no other locality on the mainland with such a varied flora and fauna, and from different environmental habitats. There are animals from the air, land, swamp and river, and the Bluff gives us a unique window into the early Cretaceous world of 125 million years ago.

Thursday, 7 October 2010

SVP 2010 - Pittsburgh


On the eve of the SVP meeting in Pittsburgh later this week, I just want to wish those of you who are going this year, a great meeting and I hope you really enjoy yourselves. I especially wish those of you who are presenting for the first time, whether poster or oral presentation, the very best of luck.

Earlier this week, I actually prepared a short concise blog entry which was a preview of some of the topics coming up for discussion during the meeting, mainly those that were of personal interest to me. As an active SVP member, I am well aware of the embargo regarding any form of coverage of abstracts and upcoming presentations during the meeting. I thought that I could construct a piece that was both informative and interesting without giving anything away, mentioning no names and no great detail.

I think it came out really well but the more I read it, the more the doubts started to creep in. I really believe that there is nothing in it that would provoke anger from anybody, it certainly reveals nothing specific – indeed it is nothing more than a taster. No, less than that – a hint of a taste.

Be that as it may, discretion is the better part of valour (stupidity?) and I’ve decided to shelve the piece until next Thursday, after the meeting has finished, and then I’ll be able to discuss things in more detail anyway, so it’s best not to chance it.

SVP 2011 – Enjoy!!!

Thursday, 30 September 2010

An Introduction to the Oxford Clay - Part 1


Having written so many blog entries regarding the Oxford clay, I figured it was time to give a brief description and introduction to this important geological unit that has provided so many wonderful vertebrate specimens over the years and continues to do so. This is the first of a couple of blog entries describing the geology, palaeoecology and fossils of this important unit.

165 million years ago, at the end of the mid-Jurassic, the continents, as we like to think of them now, were part of the super-continent known as Pangaea. This enormous land mass was almost crescent shaped and the northern and southern arms were separated by the Tethys Ocean and it was here, in this shallow warm sea, that the Oxford Clay was deposited.

The Oxford Clay is a succession of mud rocks that lie above the sand dominated Kellaways formation. These clays are occasionally intersected by horizons of carbonate concretions and are overlain by various facies that are collectively known as the Corallian Beds. Quite often, and in many places, the upper limit of the clay is a disconformity. All of these mud rocks, and the fossils they contain, are typical of a warm shallow marine environment and, indeed, this is exactly the ecosystem that we find in locations such as Quarry 4.


This extraordinarily rich ecosystem was powered by the sun. Both free floating phytoplankton and bottom dwelling benthic microflora converted the sun’s energy into organic matter via photosynthesis and, indeed, the same process more or less continues in the shallow marine ecosystems of today. Various biological groups were represented by these micro organisms which included various types of bacteria and algae. They were incredibly abundant and their fossil remains are best observed in the sediment under the electron microscope. The fact that benthic microflora are here at all is clear evidence of shallow water since they must receive sunlight to enable them to utilise the process of photosynthesis.

From the smallest to the largest - the big carnivores of this shallow sea. Marine reptiles dominated and animals such as ichthyosaurs, plesiosaurs and marine crocodiles were the rulers of the Oxford Clay ecosystem. Linking these groups together are the other threads of this web of life including the fish and a plethora of invertebrates. When palaeontologists were piecing this astonishingly diverse ecosystem together, it became apparent that there were two distinct food webs. The first was in the upper reaches of the water column dominated by phytoplankton who were the primary food producers. The second was in the lower depths of the water column where the sea floor was covered by the benthic microflora and these were the primary food producers at this level. And, of course, an additional and an obviously major source of energy at this level came from dead organic matter that fell from the upper reaches of the sea.

Sunlight alone cannot maintain a healthy and complex web of life and this was supplemented by a rich source of nutrients. But where did this come from? Throughout the Oxford Clay you find fossils of plants and animals from the land. These fossils include an array of different plant species and trees and there have been a surprising amount of dinosaur bones recovered – remnants of bloated carcasses washed out to sea. Indeed the most complete theropod found in the UK (Eustreptospondylus) was recovered from the clay. Obviously this means that ancient shorelines were nearby and rivers would have provided a continual source of nutrients into the sea. And it is again worth pointing out that many fossils in the clay are from shallow water species.


Another source of nutrients is derived from recycling those nutrients that became available when other organisms died. Anybody familiar with the clay is aware how very productive this ecosystem really was and this is very evident from the amount of organic carbon residing within the sediment as a direct result of intense biological activity. It is this high organic volume material in the Oxford clay which made it so perfect for the brick making process. And it was the brick making industry that led to the uncovering of some of the best marine reptile fossils found anywhere in the world.

In part two, I’ll go into some more details about these animals, the quarries that they have been found in and some of the people involved with their discovery.

References

Calloman, J.H. 1968 The Kellaways Beds and the Oxford Clay; pp.264-290 in P. Sylvester Bradley and T.D. Ford (eds.), The Geology of the East Midlands. Leicester University Press, Leicester, UK.

Calloman, J.H., Dietl, G and Page, K.N. 1989. On the ammonite faunal horizons and standard zonation of the Lower Callovian stage in Europe; pp.359-376 in the 2nd International Symposium on Jurassic Statigraphy, Lisboa, 1988.

Cope, J.C.W., Duff, K.L., Parsons, C.F., Torrens, H.S., Wimbledon W.A. & Wright, J.K. 1980a. A correlation of Jurassic rocks in the British Isles, pt2, Middle and Upper Jurassic. Geological Society of London, Special Report, 15:1-109.

Martill, D.M & Hudson, J.D 1991. Introduction. Fossils of the Oxford Clay. The Palaeontological Association, London, UK, 1, 11-34.

Page, K. 1989 A stratigraphical revision for the English Lower Callovian. Proceedings of the Geologists’ Association, 100, 363-382.

Thursday, 23 September 2010

2010 - The Year of the Ceratopsia


I try not to jump on the paleo-blogosphere bandwagon when there is a media explosion regarding the announcement of new dinosaurian taxa. But this time I will make an exception and make no apologies for doing so!

Since I had the privilege of chatting to Scott Sampson over dinner at SVP in Bristol, I have been waiting for the official media and journal release of these spectacular chasmosaurines. I know I’ve blogged about it before, but I cannot emphasise enough how generous Scott was in revealing so much information to both myself and Scott Moore-Faye, then the senior preparator at the British Museum of Natural History.

At that time, the chasmosaurs were known as “Taxon A” and "Taxon B”. We now know that these are Kosmoceratops richardsoni and Utahceratops gettyi and what spectacular animals they are! I won’t go into great detail about them since there is a wealth of information on so many blogs, websites and forums already and the paper is freely available at PLoS ONE.

2010 is certainly the year of the ceratopsia. A multitude of new taxa announced, the magnificent tome that is New Perspectives on Horned Dinosaurs and I know of several other new taxa to be published in the next few years. Absolutely amazing. This highlights just how very little we do actually know about the dinosaurs as a whole but things are slowly coming together. It’s a great time to be involved in dinosaur palaeontology – especially for students of ceratopsians just now.

Congratulations must go to Scott and his team for a job well done and we all look forward to their next revelations.

Wednesday, 22 September 2010

Jurassic Bark


Towards the end of February a spring-like spell of weather meant that conditions at Quarry 4 were rapidly improving and it was obvious that the quarry floor would be drying out. It was time for a return visit.

Mark and I made quick arrangements and we were soon heading to the quarry on a bright Saturday morning. When we arrived the first topic of discussion was what to wear. We went for the compromise which involved mainly spring clothing with a sweater thrown in for good measure. It turned out to be a good decision.

The quarry itself had really dried out although there were still significant pools of water. The clay was really bright grey as opposed to the dark wet grey it was on our last visit. On the horizon we could see a great swathe of clay had been removed at the back of the quarry. We moved off to prospect.

This time the walk through the quarry was much easier. There were still some areas of soft clay to negotiate but now it was much firmer underfoot overall. As we approached the new scrape we came across a newly dug trench, perhaps 150 yards in length and we both dropped into it just about central to its total length. We both started to prospect – I went one way and Mark went the other.

It was much easier to discern this time and the trench looked good. However, the more I looked, the more I realised that this trench was obviously not in a very fossiliferous part of the quarry. This is something that we have now come to realise that, despite its apparent uniformity, Bed 10 can be remarkably zonal. Some parts have mainly belemnites, some are mainly Gryphea (although this is probably due to the fact that Bed 9 intersects now and then), and the best are a mixture of everything. All are dominated by the ammonite Kosmoceras.

But this trench was sparse except every now and then there would be huge blocks of mud shales that were like leaves of a book. All the layers are ultra thin but they all contain beautiful impressions of ammonites and bivalves. Their fragility makes them impossible to collect no matter how careful you try to be. Even if you managed to pick one up you would be certain to destroy them in transit, they are that fragile.

We met up and decided to move to the new scraping. To reach it we had to climb up an awkward spoil heap on the other side of the trench. As we reached the top we looked at each other, smiled and looked below us. The new scraping looked absolutely perfect, level and smack bang on Bed 10. As Mark said “If we don’t find anything here we want our butts kicking”. I knew what he meant.

We immediately began to prospect. Just where we entered the new scraping the digger had obviously gone a little deeper than intended and huge blocks of clay were upended and this was where we started. This was the first time in this quarry that I felt really at home and with the sun beating down on us, and the first warm temperatures for more than 5 months, we just had to find something.

After our initial excitement died down we looked intensively for any sign of bone that would lead to our first significant discovery of the year. This was the first time that we had the advantage of scouring a new face and we were intent on succeeding.

After about an hour we still had nothing to show for our efforts and we started to spread out a little bit more but still maintained our very slow, deliberate and methodical search for fossil bone. Eventually I came to a slight depression and noticed a high concentration of carbonised wood fragments covering a large area.

At the Bluff, wood and bone often go together, so I decided to spend some time here and began carefully scraping at the clay. I soon uncovered what I thought was an unusually large piece of wood and it appeared fairly solid. I began to brush away the clay from one end and the piece got bigger. So I brushed more clay away from the other end and still it got bigger. I called Mark for help.


As we uncovered more of the wood we both realised we had uncovered a really unusual fossil for these marine sediments. There, lying before us was a tree trunk, nearly 3 metres long and quite obviously part of a big tree. I know that you cannot compare it with some of the big trunks in, for instance, Arizona but never the less this was a big piece of wood.

Mark initially thought it may be a species of cypress. Personally, trees aren’t my strongpoint so I didn’t have a clue as to what it was. The immediate question was that now we had uncovered it, what on earth were we going to do with it? It was far too big for either of us to have and, besides, we would need the help of an excavator to remove it.

Eventually we decided to cover it over and mark the spot with a few rocks. Then we would later notify the local museum and see if they would be interested in taking it out. This particular museum had recovered many complete and partial skeletons from this quarry and others like it the area for many years and were very experienced and we felt that they would have the best chance of removing it – if it were required.

We carried on with our search but it became apparent that, despite the ideal conditions and situation, we were doomed to failure again. We both tried hard and I can honestly say that we covered the area with the proverbial fine tooth comb, methodically prospecting as we went. We were both certain that there was nothing to find and abandoned the new scrape for pastures new.

We carried on the search for some time afterward, concentrating our efforts in areas that were underwater from the previous trip but still there were no bones to be found. Quarry 4 and I just haven’t reached a compromise yet – but we will.

We eventually called it a day and walked back to the cars, boneless but in good spirits and, as usual, vowed that it would be our turn next time. I knew that, because of other commitments, it would be most likely May before we returned and, before then, a trip to Misty Bluff was next on the list. But return we would and try yet again to find that elusive marine reptile.

Footnote

A small group from the museum were going into Quarry 4 only 48 hours after our visit to see if the tree could be removed and conserved satisfactorily. They decided it wasn’t really suitable for preservation – besides, they said, where on earth would they put it? Understandable - but still a shame.

We uncovered a tree that hadn’t seen the light of day for 160 million years. When I next returned, it had disintegrated and the last remnants were blowing away in the wind…………

Monday, 13 September 2010

Stunning Skeletons but a Lesson is Learnt


During the autumn, Mark had managed to obtain for me a pass for Quarry 4 which would allow us to visit the quarry during any weekend we wanted, subject to the quarry owners’ approval and provided we always asked permission. This also allowed time for the security teams at the quarry to be alerted to our presence.

Prior to our first independent visit to the quarry, we were to be shown around the quarry by Cliff Nicklin, which was useful since we both knew Cliff well from previous visits. This was mainly for health and safety issues although we were both very familiar with Quarry 4.

As it turned out, for various reasons, Mark and I never seemed to be free at the same weekend and it seemed that the year would be over before we could get down there together since it was a cast iron never-to-be-broken rule that there is no lone prospecting or digging in the quarry. This is a bind, for both of us, since we are both seasoned workers in these quarries and you do feel like you are being treated a little like children sometimes. But if that is the price to pay for continued access to the quarries then so be it. Never the less, we stayed in touch trying to find this mutually convenient day.

During early November, I emailed Mark to see how he was and, when he replied, what he had written almost made me fall out of my chair! Cliff had told him that they had found two more or less complete very intact skeletons of a plesiosaur and a pliosaur, almost side by side. Not only that, but a third partial plesiosaur had also been exposed not too far away. A few of them were going in to uncover more of the in situ remains and decide on a plan of excavation.

Unfortunately I couldn’t make the following weekend since Chris and I were away for a pre-Christmas break. I was obviously a little disappointed but not that much since we always enjoy our short breaks and would still do a little fossil hunting at Bracklesham Bay, somewhere that I always fancied. But Mark was definitely going and would let me know the score when I got back.

We returned on the Monday and I checked my emails and I was not to be disappointed. Waiting for me was a short message and two attached images of a magnificent pliosaur paddle, virtually intact and complete. And it was big. I instantly picked up the phone and called Mark for the detail.

The skeletons appeared fairly complete and, most important of all, they both appeared to have the skulls preserved and encased in concretions. In fact the bulk of the skeletal remains were in concretions – not totally unexpected in this quarry. Cliff was in contact with the quarry owners to arrange the extraction of the remains before word got out and the local scavengers started to illegally remove the remains.

At this point I was surprised to hear that the exposed paddle was to be left in situ and covered over until the Tuesday when it would be removed, today being the Saturday as it was. On asking why, Mark revealed that he had offered to the others the necessary consolidant and bandaging to allow quarrying to begin but that it had been deemed sensible to leave it until Tuesday! I was perturbed and I knew that Mark was as well.

Later the following week, I again spoke to Mark about getting back to the quarry and asked if the paddle had been removed OK. I was crestfallen to hear that on their return the paddle had been illegally removed. It was at this point that we realised that the recent activity in the quarry had obviously been observed by others. Although strictly off limits to the public, a public footpath skirts Quarry 4 on its northern face and we know we have been watched before by others who also have an unethical interest in the quarry – one that involves profit. Mark also revealed that the NHM had even offered a team of five palaeontologists and students to take the remains out but this too had been declined – what an error to make!

Mark couldn’t make it at the weekend so we determined to return the following weekend at first light on the Saturday. During this time we were informed that the skeletons were to be dug out of their graves and removed by the quarry workers with Cliff and others in attendance. A couple of days later we heard that the fossils had indeed been removed.


A few days later we arrived at Quarry 4. Cliff was meant to meet us but didn’t show so we were on our own and apart from the security teams there we were to have the quarry to ourselves. Frustratingly, one of the security teams revealed that someone had been spotted in the quarry on the Friday afternoon and had appeared to remove yet more material before being challenged. This was getting to be quite distressing.

We soon arrived at the bone bearing horizon and there in front of us were the gaping holes where the skeletons had been removed. It was very obvious that huge blocks had been excavated and that there would be very little to retrieve. We set about the site, however, and started to prospect.

As it turned out, we were correct and only one small section of rib was found. Not keen to waste too much time we headed to the newly scraped corner of the quarry to see if anything had been uncovered. No bone was found but we started to find small pieces of fish “bone” which actually turned out to be a species of belemnite, Belemnopsis . Apart from these there appeared to be very little else.

We then decided to look at the third site where the partial plesiosaur was situated. Again this quarry had been excavated and nothing remained although the clay here was extraordinarily rich in fossils. Mark actually found a rare small ichthyosaur tooth and then promptly dropped it never to be found. Things were not good.

As if to compound our misery Mark then proceeded to find a cracking little “bone” weathering out of the clay until closer inspection revealed it to be some form of distorted metal tubing. We were not amused. Mark left shortly after to attend to some personal matters but I remained behind to continue the search.

I did find yet more wood but several small pieces of wood found in association do actually fit together and it appears to be a twig or a sapling. Unlike the usual bits of wood found, which need instant consolidation, these bits are well fossilised and will need minimum work to make them look good.

I left Quarry 4 about an hour and a half after Mark had gone. It was great to have such a huge quarry to yourself – very atmospheric. Indeed, the only movement to catch your eye, and occasionally make you jump, were the shadows from the vanes of the wind turbines located above the quarry.

We eventually found out that the two fairly complete specimens were taken for short term loan to two educational facilities allied with Peterborough museum until, when time and money permits, they can be prepared and studied properly. The whereabouts of the partial plesiosaur skeleton is still unknown to me but it is safe to assume that it is safe and residing in a correct repository. At time of writing this article, nobody knows where the missing pliosaur paddle eventually ended up – there was no trail to follow and no clues could be found. I find it deeply disturbing that this scientifically significant specimen, our nation’s inheritance, may have been sold off illegally into the private market. This is a shame since this Peloneustes skeleton looks as if it could be one of the most complete ever found.

During the second world war, there was a saying: “Careless talk costs lives”. Well it seems careless talk and actions also costs specimens. In the future, we will not be letting anyone know that we are going to Quarry 4, no advanced warning, except for, of course, the quarry owners and those in our immediate confidence. Hopefully when the next marine reptile puts in an appearance we will be able to notify the right people and, with a bit of luck, be able to get the remains out correctly and scientifically. To do this we will need the cooperation of the quarry owners and hopefully the Peterborough and/or the Natural History Museum will be on hand to excavate the specimens.

We must ensure that a repeat of this incident never happens again and that we never lose another specimen, important to science, to goodness knows where. My only concern is that these national treasures are preserved for the future and that everyone should be able to access them, whether that is for the general public to observe them or for scientists to study them. The battle to preserve our heritage starts now!