Sorting Out Eolambia caroljonesa

The Cedar Mountain Formation of the western United States has yielded a number of important dinosaur discoveries, helping to map the megafauna of America during the Cretaceous.  Iconic dinosaurs such as the armoured herbivore Gastonia and the “raptors” Deinonychus and Utahraptor are known from the various members that make up the Cedar Mountain Formation.  However, the most abundant dinosaurs in terms of the genera named are ornithopods and a team of scientists including researchers from the Field Museum (Chicago), have published a new paper helping to identify where, in the dinosaur family tree, one ornithopod – Eolambia caroljonesa should be placed.

An Ornithopod Dinosaur Riddle

The youngest member of the Cedar Mountain Formation (a member being a distinct, identifiable portion of a rock formation that can be identified as a stratigraphic unit), is the Mussentuchit Member and the most common dinosaur fossils associated with these strata relate to Eolambia caroljonesa.

This herbivorous dinosaur is known from quite extensive fossils including skull material and three bonebeds that contain the jumbled up remains of a number of juveniles.  Named by the famous American palaeontologist James Kirkland in 1998, Eolambia means “early or dawn Lambeosaur”, reflecting the proposed taxonomic position of this dinosaur as being a basal member of the lambeosaurines (crested duck-billed dinosaurs).

Eolambia caroljonesa

Over the last two decades, since the discovery and naming of Eolambia, many more iguanodontian dinosaurs have been named.  This has helped palaeontologists to better understand the evolution of ornithopods from the non-hadrosaurid forms known from the Early Cretaceous to the duck-billed dinosaurs which were prevalent during the Campanian to Maastrichtian faunal stages of the Cretaceous (Late Cretaceous).

Writing in the on-line academic journal PLOS One, the researchers describe some further postcranial remains of Eolambia from the Mussentuchit Member.  The fossils represent a sub-adult animal and as a result, these bones are more helpful when it comes to establishing autapomorphies (unique features), that help to establish where in the dinosaur family tree Eolambia should be nested.

The Eolambia Postcranial Fossils Laid Out in an Approximate Life Position

Eolambia postcranial fossil material laid out in approximate life position.

Picture credit: PLOS One with additional annotation by Everything Dinosaur

Calculating the Size of Eolambia caroljonesa

The picture above shows the newly described postcranial fossil material laid out in approximate skeletal position, using the better known iguanodontid Mantellisaurus atherfieldensis as a template.  The scale bar equals one metre.  One of the outcomes of this new study is that the research team will be able to provide a better estimate of the true size of Eolambia.

When first named by Kirkland, this dinosaur was estimated to be around eight to nine metres in length.

However, Gregory S. Paul (2010), suggested that Eolambia was considerably smaller with a total body length of around six metres.  Having to rely on juvenile material makes estimating the adult size of a dinosaur very difficult.  The ilium (number 26 in the picture above), measures a fraction under seventy-one centimetres in length.  Everything Dinosaur team members have examined their data files and compared this measurement to the size of ilia from other iguanodontids.  For example, the ilium of the Spanish iguanodontid Delapparentia turolensis measures seventy-eight centimetres long.  As Delapparentia is estimated to have been up to ten metres in length, it is likely that a fully-grown Eolambia could perhaps measure around nine metres from nose to tail.

Comparing Eolambia Pelvic Material (E. caroljonesa)

Eolambia pelvic material (sub-adult specimen compared to juvenile material).

Picture credit: PLOS One

The picture above shows the sub-adult pelvic material representing the new specimen FMNH PR 3847 (A, B, E, F, H and K) compared to other known fossil material including juvenile remains (C, D, G, I and J).  The scale bar equals ten centimetres.  Histological analysis from a sample of rib bone indicates that this dinosaur was between eight to nine years of age when it died.

Eolambia in the Dinosaur Family Tree

Specimen FMNH PR 3847 provides new anatomical detail regarding the back bone and pelvic girdle of E. caroljonesa.  As the fossils come from a sub-adult, the scientists have been more confident in the phylogenetic assessment of where within the Ornithopoda Eolambia should be nested.  The researchers conclude that this dinosaur was only very distantly related to the lambeosaurines and that it was a basal hadrosauromorph closely related to Protohadros byrdi, fossils of which come from similarly aged rocks (Cenomanian faunal stage), from Texas (Woodbine Formation).

An Illustration of Eolambia

An illustration of the hadrosauromorph Eolambia.

Signs of a Predatory Dinosaur

The fossils were deposited in strata that was formed in a crevasse splay feature – sediment deposited when a stream breaks its banks and deposits sediment on the flood plan.  Along with the dinosaur bones the scientists identified a large number of crocodylomorph teeth and small bones and a tooth from a gar (fish).  Intriguingly, the team also found broken teeth from a large, meat-eating dinosaur.  Although, the exact taxon cannot be pinned down, the scientists postulate that these teeth could have come from Siats meekerorum, an apex predator known from similar aged strata in Utah.

Teeth Found in Association with the Eolambia Material

Views of a tooth from a gar (fish) and below a theropod tooth Siats meekerorum?

Picture credit: PLOS One

The scale bar for the single gar tooth (several views) is 0.2 centimetres, the scale bar for the theropod tooth is 0.5 centimetres.

The Eolambia species name honours Carole Jones who, along with her husband Ramal Jones, discovered the fossil site from which the first fossils of this dinosaur including the holotype material was collected.

For dinosaur models and prehistoric animal replicas: Dinosaur and Prehistoric Animal Models.

The Northernmost Camarasaurus

Scientists have announced the discovery of a Camarasaurus specimen from the state of Montana. Dinosaurs from Montana are nothing new, however, this is the first definitive evidence that this sauropod ranged as far north as the Treasure State.

Writing in the on-line academic journal PLOS One, the researchers, Cary Woodruff, the Director of Palaeontology at the Great Plains Dinosaur Museum, (Malta, Montana) and Dr John Foster (Museum of Moab, Utah) describe the partial, articulated remains of a Camarasaurus specimen from Morrison Formation exposures located in the Little Snowy Mountains, Fergus County, Montana.  The scientists conclude that further exploration of Upper Jurassic sediments may yield further dinosaur fossil material, helping palaeontologists to learn more about the ecosystem and the dinosaur fauna within it that lived in more northerly latitudes of North America.

An Illustration of the Late Jurassic Sauropod Camarasaurus

Camarasaurus dinosaur model.

The Curious Camarasaurus

The Camarasaurus genus was erected by the famous American palaeontologist Edward Drinker Cope in 1877.  Numerous fossil specimens have been collected from the Morrison Formation of the western United States, in fact Camarasaurus is represented in the Morrison Formation by more than 530 specimens, it is one of the most studied and therefore, best-known sauropods in the world.  Although it shared the Late Jurassic habitat of western North America with a number of other long-necked dinosaurs, animals such as Diplodocus, Apatosaurus, Brontosaurus and Brachiosaurus, it is by far, the most abundant sauropod taxon known from the Morrison Formation.  It also appears to have had one of the highest population densities amongst the large herbivorous dinosaurs during the Jurassic.

At the moment, a total of four species are recognised:

1. C. lentus named in 1889
2. C. grandis named in 1877
3. C. supremus named in 1877
4. C. lewisi named in 1988

The vast majority of Camarasaurus fossil remains (82%) are only identifiable down to the genus level.  The Montana remains consisting of a nearly complete skull, articulated neck vertebra, rib fragments, part of the shoulder girdle and limb bones cannot be assigned to a species, but enough of the skeleton has been recovered to confirm the Camarasaurus diagnosis.

Views of the Skull Material of the Montana Camarasaurus (GPDM 220)

Views of the skull material of the Camarasaurus found in Montana.

Picture credit: PLOS One

The picture above shows various views of the partial Camarasaurus skull (I) – right lateral view, dorsal view (II), viewed from the front (III), viewed from the rear (IV) and left lateral view (V).

Camarasaurus Specimen Claims to Fame

The fossils had been known about for some years, and the dinosaur had been nick-named “Ralph” in honour of the rancher’s land, on which the dinosaur was discovered.  Collecting began in 2005, although it has taken some years to fully prepare the specimen.  GPDM 220 may represent the most northernmost sauropod fossils yet found in the Morrison Formation.  The fossils may also represent the most northerly sauropod remains found in North America.

Scrappy fossil material ascribed to sauropods in general and Camarasaurus in specific have been found in Montana before, but this is the first time, as far as we at Everything Dinosaur are aware, that the fossils have been substantial enough to permit identification down to the genus level.

A Model of a Camarasaurus

The award-winning Wild Safari Prehistoric World Camarasaurus dinosaur model.

 Although relatively small when compared to Camarasaurus remains from Wyoming and Utah, the bones represent an adult animal, histological analysis of a core taken from the femur and an analysis of a rib bone, indicates that this dinosaur was at least thirty years old when it died (possibly older, perhaps thirty-five).  The palaeontologists speculate that Montana was not an ideal habitat for Camarasaurus, this may explain the relative small size of the specimen.  A firmer conclusion cannot be made due to the paucity of Camarasaurus specimens from northerly latitudes and the potential for under-sampling of dinosaur fossil remains in unfavourable ecosystems.

Limb Bones from the Montana Camarasaurus

Limb elements for the Camarasaurus (Montana specimen).

Picture credit: PLOS One

The picture above shows various limb elements associated with the skeleton.  An incomplete left femur (A) is shown in a posterior view (I) and distal view (II).  A partial right tibia is shown (B) in (I) anterior view, (II) posterior view and (III) distal view, whereas, (C) represents an incomplete left fibula in (I) anterior, (II) posterior and (III) distal view).  The scale bar = ten centimetres.

Hinting at More Camarasaurus Fossil Discoveries to Come

The research team are confident that further examination of Morrison Formation exposures in Montana will yield a lot more dinosaur fossil remains.  For example, the Camarasaurus fossil material was found in association with an as yet, undescribed stegosaur as well as two theropod teeth.

A spokesperson from Everything Dinosaur stated:

“The publication of this scientific paper goes to show, that the Morrison Formation, particularly those extensive exposures outside of Wyoming and Utah, can still surprise palaeontologists.  Further fieldwork will undoubtedly reveal several more specimens from Montana, adding to our knowledge of the dinosaur fauna from more northern parts of the United States in the Late Jurassic.”

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Doubt Cast Over Studies that Identified Dinosaur Proteins

One of the most controversial areas of palaeontology, perhaps within the whole of scientific endeavour, is the search for evidence of dinosaur organic remains within the fossil record.  Could “Jurassic Park/Jurassic World” ever become a reality?  In the future, could you see a Stegosaurus in a zoo or a Triceratops in a safari park?  A re-analysis of an experiment carried out a decade ago, that claimed to have identified collagen in the femur of a Tyrannosaurus rex, has cast some serious doubts.

Researchers at the University of Manchester in collaboration with colleagues at the National Museums Scotland, have concluded that the protein sequences identified in the original study did not come from the Late Cretaceous, their source was somewhat more mundane and their discovery has more to do with cross contamination from bones of other animals analysed in the laboratory.

Tyrannosaurid Fossil Material – No Proteins Though

T. rex skeleton on display at Manchester Museum.

Picture credit: Everything Dinosaur

The Search for Dinosaur Proteins

The claim that protein sequences (peptides) had been identified in 68-million-year-old T. rex fossils caused a sensation.  Remnants of organic material could have provided palaeontologists with tangible evidence, that one day, with ever increasing amounts of organic material being discovered, then it might just be possible to create animals reminiscent of these long extinct reptiles.  Prehistoric proteins might well have supplied the first possible glimpse of the steps towards rebuilding dinosaurs.  Think of it as “dinosaur cloning 101”.

To read an article that discusses the consequences of the original T. rex protein study: The Seemingly Impossible – the Hunt for Dino DNA.

The discovery, announced in 2005, was not met with universal acceptance and it caused much debate within the scientific community.  A second study, this time on a duck-billed dinosaur Brachylophosaurus (Brachylophosaurus canadensis), undertaken by the same team identified permineralised blood vessels and further evidence of dinosaur proteins: Ancient Proteins from Duck-billed Dinosaur.  This research was carried out in 2009 and replicated in 2017.  Writing in the “Journal of Proteome Research” scientists from North Carolina State University with colleagues from North-western University and the University of Texas – Austin, repeated the 2009 study and replicated the results – claiming proteins from dinosaur collagen had been found.

Brachylophosaurus Illustrated

Brachylophosaurus illustrated.

Picture credit: Houston Museum of Natural Science

Able to Repeat the Research and Reproduce the Results

One of the main criticisms of these experiments was that it was proving extremely difficult to repeat the work and get the same results.  In addition, preventing contamination of the samples was a challenge, with many scientists casting doubts on the original research, claiming the proteins found were as a result of bacterial contamination.

Dr Mike Buckley (University of Manchester’s School of Earth and Environmental Sciences), an author of the newly published scientific paper in the “Proceedings of the Royal Society B” explained:

“The discovery of proteins in dinosaur bones sent a shockwave around the world, both among scientists and the public.  It appeared that fiction was now being converted to fact through the application of new techniques.”

A team from Manchester University and the National Museums Scotland, led by Dr Buckley set out to explore the possibility of whether the claimed dinosaur peptides could have come from contamination from modern animals, given that ostriches and alligators were used as comparators and controls in the original research.  The scientists analysed samples of bone from three different ostriches and found strong matches to all of the originally reported fossil peptides from both the T. rex and the Brachylophosaurus.

This new study emphasises the need for robust authentication criteria when attempting to identify biomolecular sequence information from truly ancient fossilised remains.

Museums Rather Than Zoos the Best Place to See a Tyrannosaurus rex

The skull of the T. rex exhibit on display at Wollaton Hall (Nottingham). Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Dr Buckley stated:

“Our work set out to identify the collagen fingerprints for both ostrich and alligator and was not intending to debunk the previous studies.  However, we soon realised that our results were pulling the rug from beneath the paradigm that collagen might survive the ravages of deep time.”

Can Organic Material Survive for Millions of Years?

The big question is whether or not delicate organic remains can survive for millions of years.  There have been a number of papers published recently that have thrown up some surprising results, for example, back in 2015 Everything Dinosaur reported on the research undertaken at the Imperial College (London), that identified potential organic fibres (collagen) and cellular structures*.  

There is a growing body of evidence to suggest that the one day, we might have a much better understanding of the biology of long extinct creatures.  Microscopic remnants of collagen, a key protein within bone, has been found in several studies.  However, the survival of collagen sequences beyond 3.5 million years old has not been achieved and validated by any other team trying to replicate work carried out.

Co-author of this research and Professor of Natural History at The University of Manchester, Phil Manning, added:

“The fossil record is offering new information on a daily basis through the application of new technology, but we must never forget that when results show us something that we really want to see, that we make sure of our interpretation.  The alleged discovery of protein sequences in dinosaur bones has led many unsuccessful attempts to repeat these remarkable claims.  It seems we were trying to reproduce something that was beyond the current detection limits of our science”.

Experiments Involving the Detection of Minute Quantities of Organic Material Require the Strictest Hygiene Measures

“Flogging a dead horse” to extract DNA.

Picture credit: Dr Orlando

The researchers conclude that the controls used to constrain the evolutionary relationships between extinct and existing organisms have to be completely isolated from the subject of study (i.e. the dinosaur bone), so that the highly sensitive techniques do not pick-up residues of misleading contaminants.  This is leading to a false ceiling for other scientists to achieve, which in reality is highly challenging.  What was being described as dinosaur organic material, may just be the ghostly traces of the other organic material such as the protein sequences from the bird and reptile bones used in the research that are being picked up by the highly sensitive scientific instrumentation.

In conclusion, Dr Buckley stated:

“We are seeing something similar in our study, as to what happened with the ancient DNA world over twenty years ago when the scientific world had to recalibrate their aspirations when it came to the survival of this delicate molecule of life through deep time.  It seems that the idiom that exceptional claims require exceptional evidence remains.”

Regardless of the true nature of the dinosaur peptides, this new study highlights the difficulty of differentiating such sequences with confidence.  The results not only imply that cross-contamination cannot be ruled out, but that appropriate measures to test for the accuracy of the results stated should be further evaluated.

*To read more about the research undertaken by the Imperial College London: Fibres and Cellular Structures Observed in Dinosaur Fossils.

Everything Dinosaur acknowledges the help and support of the University of Manchester in the compilation of this article.

Visit the Everything Dinosaur website: Everything Dinosaur.