Rotator cuff pain past and present...

The bones, tendons and muscle that come together in the shoulder are usually referred to as the rotator cuff (but others use 'rotor cup' or 'rotary cuff'). In mammals the complexities of this particular anatomical feature can often bring us pain and discomfort, but dinosaurs were also no strangers to such delights. The relatively conservative anatomy that we vertebrates share so liberally, also generously allots the various aches and pains of the musculoskeletal system to all species...but I have to say that dinosaurs seemed to be able to deal with far more trauma when compared to our relatively frail bodies. The theropod (predatory) dinosaurs often display an array of healed injuries that have attracted the attention of pathologists...those who study and diagnose disease, given the skeletons of these ancient predators are often scarred with evidence of trauma (albeit not much disease!). However, before I get carried away with fractured bones, abscessed jaws and slipped discs...let me refine my tour of pain and discomfort back to the shoulder.

If I were asked to choose my favourite shoulder injury...as if that is something you might ever consider doing...there is a wonderfully sick saurian individual housed at the Indianapolis Children's Museum. This particular dinosaur was stalking around in the Late Cretaceous and is now named Gorgosaurus (literally  'fierce lizard'). Among its many injuries was a splendidly grotesque shoulder trauma that resulted in a vast lump of bone growing over the site of 'impact'. The enlarged lump of roughened healed bone can be clearly seen (below) with the the smooth surface of the unaffected shoulder blade (scapula) to the right and the coracoid to the left. These two bones combine to form the shoulder joint (glenoid) in which the upper arm (humerus) articulates. As an aside, the U-shaped bone to the far left is the wishbone (fused clavicles) of this rather oversized bird relative...you would have been hard-pushed to pull this particular wishbone, mainly due to us humans not having yet evolved.

The relative simplicity of the above shoulder complex clearly did not shield this joint from the slings and arrows of misfortune that wreaked havoc with this animals left arm. The evidence seen in this remarkable fossil clearly shows the skeletons reaction to injury, growing additional bone to stabilise the site of injury. However, the smooth surface of unaffected bone was replaced with a roughened surface over which the scapulohumeral muscles would have had to function...this would have been quite painful....that is an understatement. My own interest in this particular injury is quite personal, as I too have managed to damage my rotator cuff. Last field season, whilst juggling a 250 pound field jacketed dinosaur bone, I damaged my left left shoulder when lifting the said fossil. The trauma was minor, so initially treated with anti-inflammatory drugs, but almost a year on...I realise that I am beginning to feel a fraction of the pain that Gorgosaurus might have. It seems that my joint is also generating new bone-growth, shifting the path of some tendons and muscles in my shoulder. While my pain is irritating and providing sleepless nights...I will get this fixed in time. Looking at the impressive array of breaks, fractures, avulsions, tumour and infections on this Late Cretaceous predator, I have a newfound healthy respect for these natural born survivors.

Bright Lights and Dinosaurs Lecture...

Last week was National Science and Engineering week in the UK. The University of Manchester hosted many events for local schools and colleges, including workshops and lectures.  The Palaeontology Research group took part in the science fair, but yours truly also gave a lecture. The University just posted the lecture on the web, but I thought I might give you some insight to our wonderful world of synchrotrons, fossils and pigments!

Follow this LINK and you can even download the lecture...if you need to frighten any local wildlife!

VI International Symposium on Dinosaur Palaeontology

Occasionally an awesome dinosaur meeting appears on the horizon that you HAVE to attend. The VI International Symposium on Dinosaur Paleontology and their Environment is one such meeting. This event will run from 5 to 7 September in 2013 in Salas de los Infantes (Burgos-Spain).

More information on the meeting can be found at this LINK.

The first circular with information on this meeting can be found at this LINK.

Primera circular de las VI Jornadas Internacionales sobre Paleontología de Dinosaurios y su Entorno. 5-7 septiembre 2013, Salas de los Infantes.

El Colectivo Arqueológico y Paleontológico Salense (C.A.S.) y el Museo de Dinosaurios de Salas de los Infantes anuncian la próxima celebración de las VI Jornadas Internacionales sobre Paleontología de Dinosaurios y su Entorno, que se celebrarán en Salas de los Infantes (Burgos) del 5 al 7 de septiembre de 2013 con la colaboración de la Universidad de Zaragoza, la Universidad del País Vasco y la Universidad de Salamanca.

PREINSCRIPCIÓN

Las preinscripciones se harán desde: http://vijornadassalas.blogspot.com.es/ ; el plazo final para las inscripciones con descuento es el 31 de julio de 2013. Las tarifas serán:

Antes del 31 de julio de 2013: - Normal: 70 ?. - Estudiantes/doctorado: 35 ? Con posterioridad al 31 de julio de 2013: - Normal: 80 ? - Estudiantes/doctorado: 45 ?

INFORMACIÓN

Para cualquier información sobre las VI Jornadas visitar la siguiente página o contactar con la organización en las siguientes direcciones electrónicas. http://vijornadassalas.blogspot.com.es/ Email:caspaleontologia@gmail.comEnvío de resúmenes:http://vijornadassalas.blogspot.com.es/ Dirección postal: Colectivo Arqueológico-Paleontológico de Salas; Plaza Jesús Aparicio, 9. 09600 Salas de los Infantes (Burgos, España). Tfno. contacto: Museo de Dinosaurios de Salas de los Infantes (0034) 947 39 70 01 Segunda circular: abril de 2013 Tercera circular: julio de 2013

Twinkle, Twinkle little Star...

Today started early with a long drive from Manchester to Harwell in Oxfordshire. Many of you who have read my earlier blog postings, will know this is where the Diamond Synchrotron Lightsource lives. It is here that my colleagues and I often come to bathe fossil samples in the super-bright light that this facility produces.

However, today is a little different. I am here to give two public lectures on our work on using synchrotron light. My aim is to demonstrate how such bright light sources can probe the delicate trace of the atomic heart that beats invisibly within the very building blocks of fossils....and the echo the chemistry of the ast life that they represent. This kind of work can only be achieved by using such powerful x-ray sources.

Having given one lecture, I am sat quietly working inside the foyer of the vast research complex...catching-up on my blog. The weather outside stinks...grey, cold, windy and raining...as dusk falls, there is not a single star in the sky... it is tough separating sky from the mist swirling around the facility. But who needs stars, when you have a synchrotron lightsource that can shine a million times brighter than mere celestial bodies. This is not so much 'Like a Diamond in the Sky'...but more like one brighter than a million stars, just outside Didcot in Oxfordshire, England.

 

'Twinkle Twinkle little star

How I wonder what you are

Up above the world so high

Like a 'synchrotron' in the sky...'

...only not as bright!'

Camels on ice...

Every now and then an extinct species is discovered in the last place on Earth that you might expect to look. Today, is no exception with the discovery of a 3.5 million year old camel in the High Arctic. A Canadian research team, helped by scientists at The University of Manchester, has discovered the first evidence of an extinct giant camel in what is now a very inhospitable place (especially for camels!). The fossil was identified from the remarkable preservation of the protein collagen (that all so important flexible component in every bone of your body) from bone fragments unearthed on Ellsmere Island. The unique nature of the collegen allowed the researchers to identify it was a camel...as without this protein 'fingerprint', it was merely shattered bone and of little value. These now valuable bone fragments mark the furthest North that a camel has ever been found.

The fossils were collected over three summers in 2006, 2008 and 2010 by Dr. Natalia Rybczynski, a vertebrate paleontologist with the Canadian Museum of Nature. Some important morphological  features suggested to the team that the fossil fragments were part of a large tibia (main lower-leg bone in vertebrates with legs!). Digital files of each of the fossil bone fragments were produced using a 3D laser scanner, allowing for the jigsaw of bone pieces to be assembled and aligned.

However, even when the bone was reassembled it was still unclear as to which species the bone came from. So the researchers enlisted the help of Dr. Mike Buckley from the Manchester Institute of Biotechnology. He used the pioneering new technique called “collagen fingerprinting” to identify the animal from the type of collegen protein (below) recovered from the bone fragments.

Mike did this by extracting minute amounts the 'fossil' collagen, searching for chemical markers for the building blocks of the collegen protein (peptides). Mike was able to generate a identifiable collagen 'fingerprint' (profile) for the fossil bone, indicating he had bagged a camel! What is quite fascinating, is that the fossil species collegen 'fingerprint' was almost identical to the modern day Dromedary camal. This giant camel was roughly 30% larger than living camel species...which is pretty big. Next time your stood next to a camel...try adding 30% to its size!

Slightly warmer camel!

Dr. Rybczynski was keen to point out that, “These bones represent the first evidence of camels living in the High Arctic region. It extends the previous range of camels in North America northward by about 1,200 km, and suggests that the lineage that gave rise to modern camels may have been originally adapted to living in an Arctic forest environment.”

Dr. Buckley added,  “This is the first time that collagen has been extracted and used to identify a species from such ancient bone fragments. The fact the protein was able to survive for three and a half million years is due to the frozen nature of the Arctic. This has been an exciting project to work on and unlocks the huge potential collagen fingerprinting has to better identify extinct species from our preciously finite supply of fossil material.”

Dr. Roy Wogelius from The University of Manchester’s School of Earth, Atmospheric & Environmental Sciences analysed the mineral content from the fossil bones. His findings suggest that the processes of mineralization worked along with cold temperatures to help preserve the all-important protein-package in the bones. “This specimen is spectacular, and provides important clues about how such exceptional preservation may occur” said Dr. Wogelius.

Other fossil finds at the same site as the giant camel suggest the High Arctic camel was living in a  forest environment dominated by pines, spruce and larches, this during a warm phase in the planet planets long history of life. It was this warm-phase to the climate and favourable environment that encourage the camels to migrate so far north from their current range.

  

The identification of the High Arctic camel is described in the March 5 edition of the online journal Nature Communications.

One gait fits all: Titanosaur dinosaurs match their pace as they grow.

Researchers at the Institut Català de Paleontologia Miquel Crusafont (ICP, Spain), the universities of Zaragoza and Autonomous of Barcelona (Spain) in collaboration with the University of Manchester (UK) and University of Liverpool (UK) have just published in the journal PLOS ONE. Their study of trackways confirms that the titanosaur sauropod dinosaurs that lived in Fumanya (Catalonia, Spain) during the Late Cretaceous walked in the same way, independently of their body size.

Walking just like its giant parent, a sauropod plays 'catch-up' moving just like an adult!

In this study, palaeontologists have compared a small trackway of a titanosaur sauropod from the Late Cretaceous with those corresponding to larger animals in the same tracksite. The comparison of these trackways has helped to establish a cause-effect relationship between the gait (relative placement of feet as a function of limb movement), footprint size and body proportions of these dinosaurs.
Titanosaurs were a group of sauropod dinosaurs that had a characteristic arrangement of the femur and pelvic girdle that is reflected in the trackways that have been preserved in the fossil track record. Their gait was wide and the footprints left yield a characteristic ‘wide-gauge’ trackway. 

Reconstruction of a dinosaur from the Catalan, pre‐Pyrenees, about 70 million years ago. Credit: Oscar Sanisidro. Institut Català de Paleontologia Miquel Crusafont.

In the study published in PLOS ONE, researchers have compared trackways of specimens of different sizes and have demonstrated that they belonged to animals with many geometric similarities in their body plans. The juvenile dinosaur was basically a ‘replica’ of the adult in terms of limb proportions and shape, despite the large differences in body size. This led to the conclusion that the large and small titanosaurs moved in a dynamically similar way, probably using an ambling gait. 

Juvenile Titanosaur trackway from Fumanya, picture by Bernat Vila

Sauropod dinosaurs form the group of the largest terrestrial vertebrates that ever lived on land. They were herbivorous animals with a long tail and neck that allowed them to reach higher vegetation. The titanosaurs that lived in Fumanya in Berguedà (Catalonia, Spain), could reach up to 15 meters in length and weigh up to 15 tons, but the track of the new juvenile sauropod was roughly the same body trunk size of a large Labrador dog…a mere ~1.5 metres from hip to shoulders…some 10 times smaller than an adult of the same species.

Fumanya, a unique dinosaur site
The Fumanya sites of Fígols and Vallcebre, were declared a Site of National Cultural Interest in 2005. The paleontological site includes the ancient open-cast coal mines in Fumanya Sud, Mina Esquirol, Fumanya Nord and Tumí. On the site, which covers an area of more than 38,000 square meters, more than 3000 dinosaur footprints have been have been found and fossil remains of eggs and bones have been identified, together with tree trunks and leaves from different types of palms. It is considered to be one of the most important sites in Europe for fossil remains of dinosaurs from the Late Cretaceous.

From left to right, Manning, Vila, Egerton and Galobart collect LiDAR data on juvenile
trackway using a Z+F LiDAR unit.

Sauropod dinosaurs form the group of the largest terrestrial vertebrates that ever lived on land. They were herbivorous animals with a long tail and neck that allowed them to reach higher vegetation. The titanosaurs that lived in Fumanya in Berguedà (Catalonia, Spain), could reach up to 15 meters in length and weigh up to 15 tons, but the track of the new juvenile sauropod was roughly the same body trunk size of a large Labrador dog…a mere ~1.5 metres from hip to shoulders…some 10 times smaller than an adult of the same species.
Fumanya, a unique dinosaur site

Titanosaur trackways from Fumanya: LiDAR helps lift the detail.... see paper in PLoS One!

Fumanya, a unique dinosaur site
The Fumanya sites of Fígols and Vallcebre, is for me one of the best examples of Titanosaur trakway surface in the whole of Europe, if not the world. The paleontological site includes the ancient open-cast coal mines in Fumanya Sud, Mina Esquirol, Fumanya Nord and Tumí which were the reason behind in the discovery of the track-bearing horizons by a local school teacher. When you have over 38,000 square meters of exposure and more than 3000 dinosaur tracks...LiDAR is the only way to record, measure and analyse such a vast site. The Manchester team has been working with the ICP team on this site for nearly seven years now and we all know there are many more tracks and trails to be teased from this ancient surface using the light fantastic of LiDAR!

Bernat Vila, Oriol Oms, Àngel Galobart, Karl T. Bates, Victoria M. Egerton and Phillip L. Manning. "Dynamic similarity in Titanosaur sauropods: evidence from the Fumanya ichnological tracksite dinosaur (Southern Pyrenees)." PLOS ONE http://dx.plos.org/10.1371/journal.pone.0057408 

Bridges, bones and stressful behavior

Sometimes bones do strange things…or should I say, they are capable of remarkable feats. This living biological composite is the literal backbone of all vertebrates on Earth. It is somewhat surprising that we know so little about its behavior, mechanical properties and the impact of bone shape between species. Charlotte Brassey (a PhD student at the University of Manchester) has been exploring the wonderful world of bone behavior, but with particular focus on the size, shape and relative position of a limb in relation to its mechanical properties. One particular property Charlotte and her colleagues was interested in is ‘safety factor’. In engineering terms, the “factor of safety” of a structure is the ratio of its failure strength to the maximum stress it is likely to encounter, in the same way the safety factor of a bridge will be the largest load (and some) that it might encounter during service.

It is remarkable that the limb bones of an elephant are considered to experience similar peak stresses during locomotion as a shrew. The “Safety factor” seems to be maintained across the entire range of body masses through a combination of robusticity of long bones, postural variation, and modification of how an animal walks, trots and runs (in other words, its gait). The relative contributions of these variables remain uncertain, so Charlotte and the team tested the role of shape change in bones. She undertook X-ray tomographic scans of the leg bones of 60 species of mammals and birds, and extracted key properties on the shape and form of each bone scanned. The maximum resistible forces the bones could withstand before breaking under compression, bending, and torsion were calculated using standard equations more familiar to engineers. The studies main aim was to consider the impact of bone robusticity, curvature, and angle on safety factors, in relation to locomotion and peak dynamic forces (such as when running).

The new paper has just been published in The Anatomical Record, and explores the theory of postural adjustment to maintain safety factors. However, it seems that the animals studied had the last laugh (quack and squawk) given their idiosyncratic behavior and locomotor styles frequently overlaid the key relationships between force, bone angle, and body mass, particularly in birds. So, while it seems important that you are made of the right stuff…but it is also significant what you do with it!

Brassey, C., Kitchener, A. C., Withers, P., Manning, P. L., and Sellers, W.I. 2013. The Role of Cross-Sectional Geometry, Curvature, and Limb Posture in Maintaining Equal Safety Factors: A Computed Tomography Study. The Anatomical Record, DOI 10.1002/ar.22658

Bright Lights and Dinosaurs

This year I embark on a rather fun adventure. The splendid folks at the Science and Technology Facilities Council (STFC) have made me one of their Science in Society Fellows. My fellowship proposal was entitled 'Bright Lights and Dinosaurs' and will high-light the work that my team and I undertake at some of the brightest light sources on the planet, such at the STFC's Diamond Synchrotron (near Oxford).

I find myself tonight at the very same STFC facility writing these words...as we are currently exploring some new techniques to extract chemical information from the fossil remains. These wonderful beasties that saw fit to survive the slings and arrows of deep-time...by becoming immortalised in stone (aka, fossils).

Over the next two years I will be developing several outreach projects to help demonstrate to those who are choosing their GCSE's or wading through A-levels, that the wonderful world of science, technology, engineering and mathematics has a vital role to play in all walks of life...even extinct life! Through the scanning of dinosaur bones to the unpicking of belemnite biology and even the teasing of virtual muscle groups in high-performance computers, I hope to show how advances in science are breathing new life into ancient bones and beasties...but at the same time, show that science is splendidly exciting. So, if you know of a school that wants or needs an injection of prehistoric fun into physics or even a morphometric meddling with mososaurs, why not contact me at the University of Manchester, and I will do my best to visit your school and help you explore the wonderful world of Bright Lights and Dinosaurs.

Predator or prey....unpicking dinosaur tracks in Spain!

The Las Cerradicas dinosaur track site (dated between Tithonian–Berriasian) near Teruel in Spain is the subject of our latest paper. The Manchester team have been collaborating with a splendid group of scientists in Spain, working on seventeen dinosaur trackways that make this site a dinosaurs trackers heaven. Some of the trackways have been attributed to quadrupedal ornithopods, sauropods and theropods. However, in our paper we discuss the exposure of new track evidence that allows a more detailed interpretation of the controversial tridactyl (three-toed) trackways as well as the modes of locomotion and affinities of the trackmakers.

Trackway LCR8 preserved in level 3 as true tracks. A) Sketch of the trackway LCR8 with preserved manus tracks (redrawn from [22]). B) Picture and outline drawing of the pes-manus set LCR8.7. C) Picture and outline drawing of the pes-manus set LCR8.5. Scale (card) = 8 cm.doi:10.1371/journal.pone.0054177.g005

The team used detailed stratigraphic analysis to reveal four different levels where footprints have been

preserved in different modes. Within the tridactyl trackways, manus (hand) tracks are mainly present in a specific horizon relative to surface tracks. The presence of manus tracks is interpreted as evidence of an ornithopod trackmaker. Cross-sections produced from photogrammetric digital models show different depths of the pes (foot) and manus (hand), suggesting subtle differences in loading between the forelimbs and the hindlimbs.

Track LCR3.3 preserved in layer 3 as true track. A) Picture of the track. Note the levels 1 and 2 in the left part of the picture. Scale (card) = 8 cm. B) Photogrammetric 3D depth analysis model. The white line represents the longitudinal cross section that crosses the track from the ‘‘heel’’ pad through the digit III to the manus print. The contour-line spacing is 3 mm. The depth units are also mm. C) Cross section profile.doi:10.1371/journal.pone.0054177.g009

Several features (digital pads, length/width ratio, claw marks) of some ornithopod pes tracks from Las Cerradicas are reminiscent of theropod pedal morphology. This morphological convergence, combined with the shallow nature of the manus tracks, which reduces preservation potential, opens a new window into the interpretation of these tridactyl tracks. Thus, trackmaker assignations during the Jurassic–Cretaceous interval of purported theropod trackways may potentially represent ornithopod dinosaurs....and not our predatory friends the theropods. Moreover, the Las Cerradicas trackways are further evidence for quadrupedalism among some basal small- to medium-sized ornithopods from this time interval. So tracks can really give insight to how dinosaurs once walked.

To read more on the Las Cerradicas dinosaur track site, click HERE for the paper in the open-access journal PLOS ONE.

Chemical Ghost of 50 million year old invisible teeth!

On Friday last week our research group published another paper in Applied Physics A that reinforces the use and application of our synchrotron-based imaging technique. The technique permits us to tease-out chemical information from fossils…information that you simply cannot see with the naked eye. Such chemical maps can help us see 'ghosts' of original biological structures that only remain in very dilute concentrations in the fossil.

(a) Optical photograph of BHI-045A (main slab) containing preserved, almost complete fossil reptile skin (Squamata (Reptilia). The reptile consists of intricately preserved skin formed of individual scales, but no visibly preserved hard-tissues (i.e., endoskeleton, inset of boxed area in a). SRS-XRF map of copper (b) and sulfur (c) of BHI-045A resolving the biological material including individual scale detail (insets). Scale bar = 1cm.

The fossil specimen we study in this paper was thought to be a 50 million year old skin moult from a lizard….of some unknown variety. Our work was able to map the presence of teeth that could not be seen in visible light. Our x-ray mapping technique showed the presence of phosphorus from teeth and their precise location relative to the rest of the head and body. This is VERY important as now, our fossil skin cannot be a moult….lizards do not moult their teeth when shedding their skin….so we now know something has wiped-out (disolved) the bone, post-mortem, but preserved the skin…along with a whiff of the original skeleton, albeit the teeth. This changes how we view the taphonomy (from the Greek taphos 'burial' and nomos 'laws')…but also allows us to identify the type of lizard for the first time, based upon the geometry of the teeth.

(a) Magnified view of jaw region of lizard (BHI-045A) in phosphorus showing preserved dentition chemistry. (b) Interpretation of arrangement of preserved dentition red interpreted as teeth belonging to one jaw, blue to another; it is difficult to tell which is the upper and lower jaw. Scale bars = 5mm

This means we can now start looking for traces of animals that are totally invisible in visible light, but shine a bright chemical signature under the powerful gaze of the synchrotron. This 'x-ray vision' will enable palaeontologists to add important information on the biology, anatomy and preservation of ancient life.

Our new paper can be downloaded from this link: N.P. Edwards, R.A. Wogelius, U. Bergmann, P. Larson, W.I. Sellers, P.L. Manning. 2012. Mapping Prehistoric Ghosts in the Synchrotron. Applied Physics A, DOI 10.1007/s00339-012-7484-3