Police Investigation after Isle of Skye Dinosaur Prints Damaged

The police are hunting a man suspected of damaging two 165-million-year-old dinosaur footprints by attempting to make plaster casts of them.  The alleged vandalism occurred at An Corran beach, Staffin on the Isle of Skye.  This site is famous for its numerous dinosaur footprints and tracks that have been preserved in sandstone exposures along the shoreline.

Dinosaur Footprints Vandalised

The incident was confirmed in the official Lochaber & Skye Police Twitter feed which stated:

“Unfortunately, we can confirm we are investigating reported damage to the dinosaur footprints at Staffin yesterday. Were you in the area?  It would appear a male driving a campervan was possibly responsible for pouring plaster into two of the prints.”

One of the Three-toed Dinosaur Prints at An Corran Beach

One of the three-toed dinosaur prints from the An Corran beach near Staffin (Isle of Skye).

Picture credit: John Allan with additional annotation by Everything Dinosaur

The picture above shows one of the three-toed tracks that are exposed at low tide along the beach at An Corran.  The ten pence coin provides scale.

Middle Jurassic Footprints

The Isle of Skye is famous for its extensive dinosaur tracks and footprints.  The majority of the prints located at Staffin represent the movement of large ornithischian dinosaurs (ornithopods).  These trace fossils and others like them on the island, are helping palaeontologists to learn more about the different types of dinosaur that roamed this part of Europe some 165 million years ago.

Last December, Everything Dinosaur reported on the discovery of a series of sauropod dinosaur prints in Duntulm Castle Bay, around ten miles from the An Corran site.  This discovery helped to reinforce the view that the sediments on the Isle of Skye preserve a unique record of the large biota that existed during the Bathonian and Callovian faunal stages of the Middle Jurassic of Europe.  To hear that the actions of a thoughtless and selfish individual may have damaged these rare fossils is very sad.

To read about the discovery of the Duntulm Castle prints: Isle of Skye Sauropods and their Watery World.

Attempting to make casts or interfere with the prints could cause irreparable damage to these extremely rare trace fossils.  The local council’s Education Chairperson Drew Millar commented:

“It’s absolutely shocking that someone would go to such lengths to destroy something that’s been around for such a long time.  This is one of the major tourist attractions on Skye, some of the oldest proof of dinosaurs in this part of the world.”

Dinosaur Fossil Site Vandalism

Sadly, such incidents are becoming increasingly common.  It is not just the actions of overzealous fossil hunters, some of the recent acts of vandalism have been motivated by a desire to make money by selling fossils illegally.  In 2012, Everything Dinosaur reported on the removal of fossil dinosaur footprints from a site in the Vale of Glamorgan (Wales).

Late Triassic Dinosaur Tracks in the Vale of Glamorgan

Dinosaur tracks from the Late Triassic.

To read an article about the Welsh dinosaur fossil theft: Dinosaur Footprints Stolen from the Vale of Glamorgan.

Commenting on the reported An Corran beach fossil damage, a spokesperson from Everything Dinosaur stated:

“This is really sad news, let’s hope the damage is not too significant.  We suspect the perpetrator knew something about this particular fossil site, as the sandstone prints are usually only exposed at low tide and they are often covered by a layer of sand.  It is only after bad weather in winter that the sea washes away the sediment revealing the prints.”

Lochaber and Skye law enforcement officers have appealed for witnesses and have asked for anyone with any knowledge of the incident to come forward.

Note

Everything Dinosaur team members contacted the museum at Staffin for clarification of this story.  The incident did involve a member of the public attempting to make a plaster cast from a footprint.  However, it was a theropod footprint that was involved and not ornithopod as stated in the media reports.

Visit the Everything Dinosaur website: Everything Dinosaur.

Limusaurus – Shed Teeth as it Grew

An international team of scientists, including researchers from the Chinese Academy of Sciences and George Washington University (United States), have made a remarkable discovery regarding the early Late Jurassic Chinese theropod dinosaur Limusaurus (L. inextricabilis).  As this dinosaur grew it gradually shed its teeth and a beak formed.  This is the only example of this known from the Class Reptilia.  No other reptile extinct or otherwise, lost its teeth and formed a beak after birth.  This research could shed new light on how birds are related to dinosaurs as well as specifically addressing the process of the evolution of beaks in the Aves (birds).

Limusaurus inextricabilis

The researchers propose that young dinosaurs were carnivorous, eating insects and small vertebrates, whilst the adults were most likely herbivores.

Scientific Paper Explores the Ontogeny of the Ceratosaurian Theropod Limusaurus

Young Limusaurus dinosaurs were carnivores as they grew up they probably switched to a herbivorous diet.

Picture credit: Yu Chen

Limusaurus “Mud Lizard”

Limusaurus was named and scientifically described in 2009, from a series of fossils found in ancient “death traps”, muddy mires which the small, bipedal dinosaurs became trapped in and unable to free themselves, (the binomial name means “mud lizard that could not extract itself”, a reference to how this group of ceratosaurian dinosaurs met their fate.  A number of specimens are known ranging from youngsters, estimated to be around twelve months of age, to juveniles, sub-adults and more mature individuals estimated to have been approximately ten years old when they died.

Josef Stiegler, a graduate student at George Washington University and co-author of the scientific paper published in the journal “Current Biology” stated:

“For most dinosaur species, we have few specimens and a very incomplete understanding of their developmental biology.  The large sample size of Limusaurus allowed us to use several lines of evidence including the morphology, micro-structure and stable isotopic composition of the fossil bones to understand developmental and dietary changes in this animal.”

Nineteen Specimens – Placed into Six Ontogenetic Stages

In total, the team had nineteen fossilised skeletons to study.  Anatomical comparisons and CT scans of the jaws and skull helped the scientists identify six distinct ontogenetic stages (stages of growth).

Co-author of the study, James Clark, (Ronald Weintraub Professor of Biology at the George Washington University’s Columbian College of Arts and Sciences), explained that by looking at how this dinosaur changed as it grew up, they could see that over time, individuals lost their sharp meat-eating teeth.  By the time these dinosaurs had reached adolescence they were toothless and they did not grow another set as mature adults.

The Remarkable Ontogeny of Limusaurus

Limusaurus inextricablis – as these dinosaurs grew they lost their teeth and they developed a beak.

Picture credit: George Washington University

Indentifying Ontogenetically Variable Features in Limusaurus inextricabilis

Seventy-eight ontogenetically variable features were identified in the specimens.  Palaeontologists are aware that many ornithischian dinosaurs such as ceratopsids (horned dinosaurs) and the duck-billed dinosaurs, change dramatically as they grow into adults, such dramatic changes in an animal’s appearance have not been extensively documented in the Theropoda.  Despite the changes as Limusaurus grew up, the assessment of where this theropod is nested in the ceratosaurian family tree remains relatively unchanged.

The Differences Between Individual Dinosaurs at Different Growth Stages

A juvenile Limusaurus (top) compared to an adult (bottom).

Picture credit: Journal of Current Biology

Key

(1) straight (juvenile) or ventrally deflected (sub-adult) anterior end of the dentary (downward pointing lower jaw).

(2) relatively deep (juvenile) or elongate (sub-adult) skull.

(3) gastroliths absent (juvenile) or present (sub-adult).

(4) short (juvenile) or elongate (sub-adult).

Commenting on the significance of their research, Dr James Clark, (George Washington University) explained:

“This discovery is important for two reasons.  First, it’s very rare to find a growth series from baby to adult dinosaurs.  Second, this unusually dramatic change in anatomy suggests there was a big shift in Limusaurus’ diet from adolescence to adulthood.”

A Carnivore and then Herbivore

The Limusaurus specimens that represented stage 1 (very youngest animals), had a total of forty-two teeth.  Stage 2 had thirty-four, whilst in the most mature stages from stage 4 onwards, the specimens were toothless (edentulous).  Gastroliths were found in association with larger individuals, and significantly, the size and number of the stones seemed to increase as the dinosaur matured.  The presence of stomach stones indicates a herbivorous diet, a switch from meat-eating to plant-eating as the dinosaur grew up was also suggested by carbon and oxygen isotope analysis from bone samples.

Carbon Isotope Composition of L. inextricabilis Compared to other Dinosaurs from the Upper Shishugou Formation

Bone carbon and oxygen isotopes show a change in diet for Limusaurus as it grew older.

Picture credit: Current Biology

The diagram above shows the carbon/oxygen isotope analysis from the Limusaurus fossil material.  Blue polygons show the ranges for herbivorous behaviour, whilst the red polygons show likely carnivorous feeding behaviour.  The various Limusaurus ontogenetic ranges are plotted.  Growth stages one to three indicate likely meat-eating habit in young and juvenile Limusaurus specimens, with a switch to a plant-eating diet (later stages).  The data is plotted alongside meat-eating, plant-eating contemporaries of Limusaurus from the Upper Upper Shishugou Formation (Oxfordian faunal stage of the early Late Jurassic).  The dashed lines represent the data related to sub-adult Limusaurus.

Close to the Bird Lineage

Limusaurus belongs to that part of the Theropoda that is believed to be closely allied to the evolutionary ancestors of the birds.  Dr Clark et al in the formal description of this dinosaur in 2009, described the species’ hand development (manus) and noted that the reduced first digit might have been transitional towards the digit configuration of modern birds (digits II, III and IV).  This new data could help scientists to understand how birds lost their teeth and the beak evolved.

To read an article on the naming and describing of Limusaurus: Chinese Ceratosaur and Dinosaur/Avian Links.

Everything Dinosaur Comments

Commenting on why these dinosaurs adapted to a different diet as they grew older, a spokesperson from Everything Dinosaur said:

“The adoption of a new feeding strategy as the animal matured might reflect a degree of opportunism by this species.  Faced with an abundance of plant food within easy reach, it might have been advantageous for this dinosaur to feed on vegetation rather than expanding energy in the pursuit of prey.  Perhaps, as the animal grew, plant food became an increasing proportion of its diet, this dinosaur transitioning from a carnivore/omnivore phase through to a stage where plant matter made up by the far the greatest proportion of its calorific intake.”

For theropod dinosaur figures and prehistoric animal models: Everything Dinosaur Prehistoric Animal Models.

The research was performed by Shuo Wang of the Capital Normal University and Mr. Stiegler under the guidance of Xu Xing of the Institute of Vertebrate Palaeontology and Palaeoanthropology, and Dr Clark.  A National Science Foundation grant funded the research.

The scientific paper: “Extreme Ontogenetic Changes in a Ceratosaurian Theropod” published in the journal “Current Biology”.

Visit the website of Everything Dinosaur: Everything Dinosaur.

Analysis of the Genome of an Inuit Population Hints at Denisovan Influence

A team of international scientists including researchers from the New York Genome Centre and the University of California Berkeley, have analysed the genome of a population of Inuit from Greenland and identified components that may originate from the Denisovans or a related archaic human species.

The “caveman” genes have helped these people adapt and survive in cold climates.  In the first genomic analysis of Inuit people from Greenland, the scientists scrutinised two genes, namely TBX15 and WARS2 that seem to be a close match to an archaic human genetic variant, potentially Denisovan or some other closely related Denisovan-like species that has yet to be found in the fossil or anthropological records.

TBX15 is known to help the human body cope with cold temperatures and influences the distribution of body fat, whilst WARS2 encodes the mitochondrial tryptophanyl-tRNA synthetase and may have a role in managing blood vessels associated with the heart.

Who are the Inuits?

The Inuit are collection of culturally similar peoples that inhabit the Arctic regions of Alaska, Canada and Greenland.  Although widespread throughout the Arctic Circle, most anthropologists believe that the ancestors of the Inuit people originated from Siberia.  The Inuit have made their home in one of the harshest environments on Earth and their traditional lifestyle is based around hunting.  As a result, their diet is rich in protein, low in carbohydrates and despite the lack of agriculture and plant cultivation, the people derive vitamins and other trace elements essential to health from fish/meat based foods supplemented by seasonal berries, herbs and edible seaweeds.

Dr Fernando Racimo (New York Genome Centre) and a co-author of the scientific paper published in the “Journal of Molecular Biology and Evolution” commented:

“The Inuit DNA sequence in this region matches very well with the Denisovan genome, and it is highly differentiated from other present-day human sequences, though we can’t discard the possibility that the variant was introduced from another archaic group whose genomes we haven’t sampled yet.”

Who were the Denisovans?

The Denisovans are a third species of hominin, closely related to Neanderthals but distinct enough to be regarded as a separate human species.  In 2008, scientists excavating 40,000-year-old cave deposits in southern Siberia, unearthed a single tooth and a tiny finger bone.  The tooth can from an adult human, the finger bone from a child.

Genetic analysis of nuclear DNA extracted from the digit gave the researchers quite a surprise.  When this DNA was compared to that genome of modern humans and Neanderthals, it was different.  Here was evidence of a new species of hominin that lived until quite recently.  This new species was named “Denisovan” after the cave in which the bone and the tooth were found.  The Denisovans, evidently had brown hair, eyes and dark skin, at least, this is indicated by the genetic information retrieved from the single finger bone.

To read an article about the discovery of the Denisovans: X-woman! A Third Species of European/Siberian Early Human Discovered.

A View of the Entrance to the Cave (southern Siberia) Where Denisovan Fossil Evidence was Found

A view of the entrance to the cave, inside which, fossil evidence of Denisovans was found.

Picture credit: Max Planck Institute

Studying the Denisovan Genome

Intriguingly, geneticists have also found an overlap between the Denisovan genome and that of some modern groups of Asians and Pacific Islanders.  A number of theories regarding this have been put forward, for example, it has been suggested that Denisovans living in eastern Eurasia interbred with modern humans that were migrating into the region.

When these modern human pioneers reached outlying islands of the Asian continent such as Papua New Guinea, they brought the mixed H. sapiens/Denisovan DNA within that population, leading to the “echo” of Denisovan DNA found today.  Other researchers have argued that the enigmatic Denisovans were much more widespread, ranging far across Asia, although the lack of fossil evidence and calculated genetic diversity contained within a population, indicates that Denisovan numbers were never very high.

Further information regarding the spread of modern human species and the influence of archaic human lineages on the genomes of modern people: Out of Africa Earlier Than Thought!

The research team analysed the genomes of around two hundred Inuit from Greenland in order “to identify genes responsible for biological adaptations to life in the Arctic.”  They conclude that the Inuit variant of the TBX15/WARS2 region first came into modern humans from an ancient human line.

For models and replicas of ancient hominins: Safari Ltd Prehistoric Animal and Human Models.

A Lateral View of the Ancient Human Molar Ascribed to the Denisovan Species

Ancient human tooth, ascribed to Denisovan.

Picture credit: Max Planck Institute

Denisovan Genes in Tibetans

Passing on genetic material due to interbreeding between hominin species, that favoured modern humans and helped them adapt to harsh environments is not a new phenomenon.  The modern-day inhabitants of the Tibetan plateau are able to cope with living at high altitude as they have a gene variant that enables them to regulate their production and use of haemoglobin more effectively. Genetic analysis suggests that this characteristic came from the Denisovans.

Professor Rasmus Nielson, the lead author of the scientific paper stated:

“We have very clear evidence that this version of the gene came from Denisovans.  This shows very clearly and directly that humans evolved and adapted to new environments by getting their genes from another species.”

Visit Everything Dinosaur’s website: Everything Dinosaur.