Category: Palaeontological articles

Renowned Palaeontologist Jack Horner Will Join Chapman University as Presidential Fellow

John “Jack” Horner to join Chapman University (California)

John R. “Jack” Horner, one of the world’s leading experts in palaeontology, MacArthur “Genius” Grant recipient and inspiration for the character of Alan Grant in the “Jurassic Park” movies, will join Chapman University in Orange, California as a Presidential Fellow, beginning in the autumn of next  year . He retires on June 30th, 2016 from a distinguished thirty-three year tenure as Regents Professor of Palaeontology at Montana State University and curator of palaeontology at the Museum of the Rockies (Bozeman, Montana).

John “Jack” Horner – To Join Chapman University

A new appointment for the distinguished palaeontologist.

A new appointment for the distinguished palaeontologist.

Picture Credit: Chapman University

Commenting on the appointment, Dr. Daniele Struppa, Chancellor and President-designate of Chapman University stated:

“I am delighted to announce that Jack Horner, one of the most creative living scientists, will join us as a Presidential Fellow in the next academic year.  We are not hiring Jack for our acclaimed film programme, nor for a palaeontology programme – we don’t have one – but rather for his unconventional and extremely successful approach to creativity and learning.  It is his ingenuity and his sense of curiosity and wonder that he will bring to Chapman as we continue to re-think the meaning of education and how students learn.”

For Horner, as he will be seventy when he takes up the appointment, the warmer climate in California might have helped tip the balance.  He will most certainly be missed after his remarkable career in Montana.  Everything Dinosaur reported on his retirement announcement back on the 18th of this month: Jack Horner Announces His Retirement (Well Almost)

With his tremendous energy and enthusiasm, he will be taking on a number of new challenges.  Speaking about his new role, he explained:

“I’m coming to Chapman because of its strong commitment to nurturing curiosity, inquisitiveness and creativity in all aspects of academia,  I very much look forward to helping Dr. Struppa and his staff create an integrative educational environment that accepts all learning styles.”

Looking Forward to the New Challenge

Last month, Horner spoke at Chapman University’s first annual Dyslexia Summit: Strength in Cognitive Diversity, where he recounted his inspirational life story.  As a child with undiagnosed dyslexia, he struggled in school and later dropped in and out of college, attending the University of Montana for seven years.  Although he never completed a formal degree, the University of Montana awarded him an honorary doctorate of science in 1986 due to his astonishing list of achievements in the field of palaeontology.

Among other ground-breaking accomplishments, Horner and his teams discovered the first evidence of parental care in dinosaurs, extensive nesting grounds, evidence of gigantic dinosaur herds, and the world’s first dinosaur embryos.  Horner’s “outside the box” thinking skills led him to ask why no one had thought yet of slicing open fossilised dinosaur eggs – and the result was the discovery of the delicate embryos, fossilised in place.  He was a leader in the now-widely-accepted theory that dinosaurs were warm-blooded, social creatures more like birds than cold-blooded animals like lizards.

Helping to Popularise the Study of the Dinosauria

Horner has named several new species of dinosaurs, including Maiasaura, the “good mother reptile.”  Three dinosaur species have been named after him.  He has published more than a hundred professional papers, eight popular books and fifty popular articles.   His book “Digging Dinosaurs” was lauded by New Scientist magazine as one of the two hundred most important science books of the 20th century.

Horner was the technical advisor for Steven Spielberg on all four movies in the “Jurassic Park” franchise, including this past summer’s global hit “Jurassic World”.  He also helped inspire the lead character Alan Grant, portrayed by actor Sam Neill in the first and third films.

Awarded the famed MacArthur “Genius” Grant in 1986, Horner has received many other honours and awards.  Most recently, in 2013, he was awarded the Romer-Simpson Medal, the highest honour given by the Society of Vertebrate Palaeontology, for his lifetime of achievement in the field.  Earlier this year, he was recognised as one of the world’s top twenty-four scientists by Newton Graphic Science magazine.

Everything Dinosaur acknowledges use of the press release from Chapman University as supplied by Mary Platt (Director of Communications and Media Relations) in the compilation of this article.

Dakotaraptor Compared to Utahraptor

Dakotaraptor Compared to Utahraptor

The vast majority of the dromaeosaurids known were actually rather small when compared to other types of Theropod dinosaur.  As a group, these active dinosaurs were geographically widespread with fossil specimens found in Asia, both North and South America and even England (Nuthetes destructor).  All species described to date were predatory and they certainly seemed to have been amongst the most adaptable of all the Theropoda.  Over the last few years our view of these feathered terrors has changed.  They are no longer confined to the role of swift cursorial (running) hunters, scientists have proposed that many members of the Dromaeosauridae were excellent climbers (scansorial), tree dwellers (arboreal) and that a number of them were volant (capable of powered flight or gliding).

Dromaeosaurids like Changyuraptor Seemed to have Filled a Variety of Ecological Niches

"Four winged" terror

“Four winged” terror

Picture Credit:  S. Abramowicz

The illustration above depicts the dromaeosaurid Changyuraptor yangi from Liaoning Province (China), it was very probably capable of flight.

Giant Raptors – Gigantism in the Dromaeosauridae

Over the dromaeosaurids long evolutionary history, gigantic forms did evolve and we suspect that Cretaceous-aged strata still hold the undiscovered remains of a number of super-sized dromaeosaurids.  With the naming and describing of Dakotaraptor (D. steini), the Hell Creek Formation can now boast a gigantic sized raptor amongst its faunal members.  At around five and a half metres in length Dakotaraptor was a sizeable beast, but for the moment, the dinosaur called Utahraptor (U. ostrummaysorum) which roamed what was to become the State of Utah more than fifty million years before Dakotaraptor evolved, is regarded as the largest.

Direct comparisons are difficult, the two individuals that represent Dakotaraptor (a gracile form and a more robust specimen) are known from only fragmentary remains, limb bones, vertebrae including caudal vertebrae, for example.  The holotype of Utahraptor is also fragmentary, consisting of some cranial material, a tibia and caudal vertebrae.  Some further fossil material assigned to Utahraptor has come to light since Utahraptor ostrummaysorum was formally named and described, but even so, direct comparisons between these two North American giants is difficult.

Comparing Claws

Ironically, there is one part of these two dinosaurs that we can compare and contrast.  The famous sickle-toe killing claw, what is termed the pedal ungual II.

The Sickle-Toe Claws of Utahraptor and Dakotaraptor Compared

Comparing those "killer claws".

Comparing those “killer claws”.

Picture Credit: Robert DePalma with additional annotation by Everything Dinosaur

In the photograph above, a cast of the second toe claw of Utahraptor (left) is compared to that of Dakotaraptor (right).  The claws are very similar in size, although the degree of curvature is different.  In addition, Dakotaraptor had a more pronounced flexor tubercle (the ringed area in the photograph).  This would suggest that the second toe claw of Dakotaraptor was highly mobile dorsoventrally (it could be moved up and down really well).  This might indicate that Dakotaraptor, already nick-named D-raptor, was more capable of slashing with its second toe and with some considerable force too.

When the proposed femur to tibia bone ratios are compared between Utahraptor and Dakotaraptor, it can be seen that D. steini had body proportions very similar to the much smaller dromaeosaurids such as Dromaeosaurus.  Utahraptor’s hind legs seem to have been more robust and as a result Utahraptor may have been a heavier animal, but in a sprint Dakotaraptor probably had the edge.  Both dinosaurs could very probably outrun even the most talented athlete.

The presence of this new predator expands the record of Theropod diversity in Late Cretaceous Laramidia, adding a new dimension to the ecology and food chains that likely occurred in North America towards the end of the Mesozoic.

Why Dakotaraptor steini?

The genus name translates as “robber or thief from Dakota”, whereas the trivial name honours American palaeontologist Walter W. Stein.

Eggshells Tell Scientists About Dinosaur Body Temperatures

Endotherms or Ectotherms the Debate Gets “Egg-citing”

The debate as to whether dinosaurs were warm-blooded (endothermic) like mammals and birds or cold-blooded (ectotherms) like crocodiles and lizards, has taken a further twist with the publication of a study published in the journal “Nature Communications”.  Scientists have used a new method to chemically analyse dinosaur eggshells which has helped them gauge the long extinct animal’s body temperature.  Armed with this data and an estimate of the temperature of the surrounding environment, the researchers can postulate about whether dinosaurs had high metabolic rates and active life-styles or whether like alligators and lizards they tended to be only capable of short bursts of activity.

The team’s findings suggest that dinosaurs were neither true endotherms or completely ectothermic, but somewhere in between – mesotherms.  In addition, as two different types of dinosaur produced different results, this new study indicates that body temperature differed between dinosaur genera.

Research Suggests that Oviraptorid Dinosaurs were Mesothermic

"Conch Thief" feeding by the lake shore.

Not warm-blooded or cold-blooded but somewhere in between.

The conclusions drawn by the scientists are similar to those made by a team of American researchers who reported in 2014.  Following an extensive analysis of the histology and ontogeny of fossilised bones (analysis of bone cells and growth) these scientists concluded that dinosaurs were probably mesotherms.

To read more about the 2014 research: Goldilocks and Dinosaurs the warm-blooded/cold-blooded Debate

Why All the Fuss?

The argument as to whether the Dinosauria were endothermic or ectothermic has raged for over 150 years.  It was once thought that dinosaurs were slow-moving, sluggish, very lizard-like creatures.  They had to bask in the sun or rely on other external sources of heat to help warm their bodies before they could become active.   This meant that they were probably not very active at night, it also suggested that they had similar life-styles to extant reptiles such as crocodiles, snakes and lizards.  These creatures can be very mobile, but only for short periods and they soon become tired.  Thomas Henry Huxley (1825-1895), was one of the first scientists to challenge this view.  He argued that birds and dinosaurs were closely related.  In the 1960’s there was a revolution in thinking with regards to dinosaurs.  John Ostrom’s work on the Theropod dinosaur Deinonychus led to dinosaurs being depicted as much more agile, fast-moving animals.  Ostrom produced carefully argued and extremely detailed studies on dinosaur biology and anatomy and he depicted them as much more bird-like creatures capable of complex behaviour – more reminiscent of today’s mammals than like today’s reptiles.

Dynamic Dinosaurs – Active and Agile Animals

Robert Bakker (student of John Ostrom) championed the agile, active dinosaur theory.

Robert Bakker (student of John Ostrom) championed the agile, active dinosaur theory.

Robert Bakker, a student under the tutelage of Ostrom developed these ideas further and portrayed dinosaurs as warm-blooded creatures, it was Bakker who produced the famous illustration of Deinonychus shown above and it was Bakker who influenced a lot of thinking regarding the Dinosauria with his ground-breaking book “The Dinosaur Heresies”, which was published in 1986.

A Study of Rare Isotopes 

The research team utilised a pioneering procedure which allows the internal temperature of female dinosaurs to be plotted by analysing the behaviour of two rare isotopes found in calcium carbonate, a key ingredient in eggshells.  A total of nineteen dinosaur eggs were included in the study, they represent two very different types of dinosaur.  Eggshells from Argentina came from a large Titanosaur (Sauropoda), the eggshells collected in the Gobi desert, Mongolia, represent fossils from a small Theropod dinosaur, an oviraptorid.  The isotopes oxygen-18 and carbon-13 tend to cluster together at colder temperatures.  The amount of clumping enabled the scientists to calculate the body temperature of the mother.  Chemical analysis of the surrounding rock matrix permitted the researchers to estimate the temperature of the palaeoenvironment at around the time the eggs were laid.

The analysis of these eggshells, all of which were collected from Upper Cretaceous strata, suggest that the Titanosaur’s body temperature had been around 38 degrees Celsius at the time of laying.  This is a little higher than our own internal body temperature (37 degrees Celsius).  The implication is that the Titanosaur had an internal body temperature similar to that of a endotherm, although it has to be considered that the huge gut of this giant herbivore, essentially an enormous, heat-producing digestive vat would probably have influenced the internal temperature.  The sheer size of the animal, volume compared to surface area, would have probably helped it to maintain a relatively constant body temperature.  Thermo-regulation for such large animals is not so much as trying to keep warm, heat loss from a large body is much less severe than with a small animal, for example.  In the case of the Titanosaurs, once they warmed up they probably stayed warm for a very long time, keeping cool could have been more of a problem (that’s why African elephants have big ears).

Typical Titanosaur Eggs

An example of Titanosaur fossil eggs.

An example of Titanosaur fossil eggs (Hypselosaurus).

Picture Credit: Everything Dinosaur

The results from the much smaller oviraptorid paint a different picture.  These dinosaurs were very closely related to birds, but the body temperature plotted is much lower than an endotherm.  The scientists calculated that the Theropod had an internal temperature of around 32 degrees Celsius, but this was at least six degrees warmer than the environment.  This suggests that oviraptorids, dinosaurs that were closely related to birds were able to raise their body temperatures above that of their surroundings.

Commenting on these results, lead author Robert Eagle (University of California Los Angeles) stated:

“The temperatures we measured suggest that at least some dinosaurs were not fully endotherms [warm-blooded] like modern birds.  They may have been intermediate, somewhere between modern alligators and crocodiles and modern birds”.

This study supports the idea that dinosaurs could produce heat internally and raise their body temperature higher than their surrounding environment, but they were unable to maintain this temperature at a consistent level like a mammal or a bird (endotherms).  The scientists conclude that if the dinosaurs were mesothermic, they were probably more active than alligators but not as active as birds or mammals.  The international research team state that they could not observe any strong evidence either for ectothermy or endothermy in the species examined.  The body temperatures calculated for the Titanosaur and the oviraptorid indicate that variable thermoregulation likely existed among non-avian dinosaurs and that not all dinosaurs had body temperatures in the range of that seen in extant birds.

Link to an article published in June 2015, that postulates that the Dinosauria were endothermic: Dinosaurs were Warm-blooded Debate Hots Up

The Hands and Feet of Homo naledi

Two New Papers Published on Homo naledi

Two new papers on the latest hominin to be added to the human family tree have just been published in the academic journal “Nature Communications”.  Less than one month has passed since Everything Dinosaur blogged about the amazing fossil finds in the Rising Star Cavern, part of a cave system located in an area known as the Cradle of Human Kind close to Johannesburg.   Researchers from the Evolutionary Studies Institute (University of Witwatersrand), in association with National Geographic, the Department of Science and Technology and the National Research Foundation of South Africa announced the discovery of a new species of hominin – Homo naledi.  These papers focus on the anatomy of the hands and feet respectively, but why the fascination with the fingers and toes of this South African species?  The explanation is simple, the hands and feet can provide scientists with valuable information as to how human H. naledi may actually have been.

The Hand and Foot of Homo naledi

The hand and the foot of Homo naledi.

The hand and the foot of Homo naledi.

Picture Credit: Peter Schmid and William Harcourt-Smith, Wits University

Good at Climbing but also Adapted for Bipedal Walking

The papers reflect just how remarkable the discovery of Homo naledi was.  The first point to make is that palaeoanthropologists do have a lot of bones to study.  In total, some 1,550 numbered fossil elements have been retrieved from the difficult to access cave.  Taken together these two papers indicate that this human-like creature, was uniquely adapted to both an arboreal existence (tree climbing) and walking on the ground.  In addition, the structure of the bones in the hand suggest that these hominins were capable of intricate hand movements and precise manual manipulation.

The titles of the two papers, state precisely what they are about, full marks to the research team for their brevity.  No long-winded titles here, these papers do “exactly what it says on the tin.”

  1. The foot of Homo naledi
  2. The hand of Homo naledi

The research were conducted by a team of international scientists associated with the Evolutionary Studies Institute at the University of the Witwatersrand in South Africa, home of the Rising Star Expedition team that made the 2013-discovery at the Cradle of Human Kind.  According to the researchers, when considered together, these papers indicate a decoupling of upper and lower limb function in H. naledi, and provide an important insight into the skeletal form and function that may have characterised early members of the Homo genus.  An evolutionary tree that eventually led to our own species Homo sapiens.

The foot of Homo naledi

Lead author, of the paper published on the pes (foot), William Harcourt-Smith and his colleagues describe the H. naledi foot based on 107 foot bones recovered from the floor of the Denaldi Chamber (Rising Star), including a well preserved adult right foot.  They show the H. naledi foot shares many features with a modern human foot, indicating it is well-adapted for standing and walking on two feet (bipedalism).  However, there are differences from the bones found in the foot of a Neanderthal, or our own feet for that matter.  For example, the authors note that the Homo naledi foot differs in having more curved toe bones (proximal phalanges) and the arch of the foot is not so pronounced.

The hand of Homo naledi

Lead author, of the paper that describes the hand, Tracy Kivell (University of Kent) and her colleagues describe the hand of Homo naledi based on an assessment of approximately 150 hand bones from the cave.  One of the key finds was a nearly complete adult right hand (manus), it was missing one small bone in the wrist.  This is an exceptionally rare find in the human fossil record.  As the tiny toe and finger bones were found in a number of cases in almost perfect articulation, this rules out the possibility of water having run through the cave at some point after the bodies came to be at that location.  Running water would have scattered the bones but the scientists found this not to be the case.  It is likely that the bodies have remained undisturbed, this suggests that the corpses may have been deliberately placed in this part of the cave system.  For such a small-brained hominin to show care for the deceased is very unexpected and more research is required to date the fossils and to try to understand how the remains of at least fifteen individuals came to be in the cavern.

The Delicate Finger Bones Preserved in Articulation in the Cavern

The hand of Homo naledi

The hand of Homo naledi

Picture Credit: Marina Elliott

The H. naledi hand reveals a unique combination of anatomy that has not been found in any other fossil human before.  The wrist bones and thumb show anatomical features that are shared with Neanderthals and humans and suggest powerful grasping and the ability to use stone tools.  The thumb is particularly robust, this is a trait only found in recent hominins.

However, the finger bones are more curved than most early fossil human species, such as Lucy’s species Australopithecus afarensis, suggesting that H. naledi still used their hands for climbing in the trees.  This mix of human-like features in combination with more primitive features demonstrates that the H. naledi hand was both specialised for complex tool-use activities, but still used for climbing locomotion.

Commenting on the significance of the Homo naledi hand, Dr. Kivell stated:

“The tool-using features of the H. naledi hand in combination with its small brain size has interesting implications for what cognitive requirements might be needed to make and use tools, and, depending on the age of these fossils, who might have made the stone tools that we find in South Africa.”

Age is the Key

More research will be carried out into this remarkable South African fossil discovery.  The key question is determining the age of the fossils.  Obtaining an accurate date for Homo naledi would help palaeoanthropologists place this species within the human lineage.  For example, this could be a tool-using, human-like creature that lived some three million years ago, or perhaps a more recent member of the hominin family, a human-like creature that retained some ancient Australopithecine traits that survived until much more recently.  This latter scenario is not that far-fetched, discoveries on the Indonesian island of Flores stunned the world of anthropology when it was revealed that a dwarf species of human (Homo floresiensis) had lived on the heavily forested island until, perhaps, as recently as 12,000 years ago.

The paper on the hand, opens up a debate amongst scientists.  The hand looks capable of intricate manipulation, indicating tool usage, but the brain of Homo naledi is estimated to have been not much bigger than a chimps.  If the hypothesis is correct, that the use of tools changed the shape of the bones in the hand, then the implication is that a small-brained hominin was making and using complex tools.  Comparing the hand anatomy to our own species and to that of the Neanderthal (H. neanderthalensis), Dr. Kivell commented

“They [Neanderthals and humans] make tools, complex tools, and use them all the time, enough so that it’s actually changed their morphology.  Perhaps naledi was using tools that were made out of different materials or doing some other forceful, precision-grip manipulations, but the most straight-forward explanation is that naledi is making and using tools.”

This may be the most straight forward explanation but there may be other reasons why those hands are so human-like.  Analysis of the teeth will provide a detailed picture of the diet of these creatures.  If, as has already been proposed that they were largely vegetarian, then the hands could have evolved grasping and manipulation traits to help them search for seeds, to pluck fruits and to hold small items of food.  Clearly, the Rising Star fossils will provide scientists with a unique opportunity to learn more about hominin evolution.  Now, if we can only get an accurate date…

To read about the cave discovery: Homo naledi A New Species of Hominin from South Africa

Everything Dinosaur acknowledges the help and assistance of the media team at the University of Witwatersrand in the compilation of this article.

“Bent Fence Post” Turns out to be Woolly Mammoth Fossils

Farmer Finds Partial Woolly Mammoth Fossil in Field

Farmers in certain parts of the south-west of England can occasionally turn up pieces of Ammonite fossil as they plough their fields, but a farmer from Michigan came up with an elephant-sized surprise when he and a neighbour were digging in their soya bean field.  They have unearthed the partial skeleton of a male Woolly Mammoth, one that is believed to be between 10,000 and 15,000 years old.

James Bristle a resident of Washtenaw County (west of Detroit), thought he had uncovered something a little more prosaic, when he excavated a “wood-like” object, he explained:

“We thought it was a bent fence post.  It was covered in mud.”

However, upon closer inspection the strange object, started to look more like bone.  It turned out to be a rib bone from the extinct elephant.  The grandson came over to take a look and he was speechless, quite a feat when you consider just how noisy most five-year olds are.  Mammoths and Mastodons roamed North America until the latter stages of the Pleistocene Epoch, this specimen may represent one of the last Woolly Mammoths to have lived in this part of this world.  Just a few thousand years, perhaps in this animal’s case, just a few hundred years later, all the prehistoric elephant species of North America had become extinct.

A Model of a Woolly Mammoth

Woolly Mammoth Model without the usual brown coat

Woolly Mammoth model, typical of this type of prehistoric elephant.

Picture Credit: Everything Dinosaur

Confirmed by Palaeontologists

University of Michigan Professor Dan Fisher has been leading the excavation, to remove the animal’s remains before exposure to the air invites further decay of the bones and teeth.  The partial skeleton consists of the skull, pelvis, two, huge curved tusks, the shoulder blades and numerous vertebrae and rib fragments.  About thirty Woolly Mammoth fossilised skeletons have been reported from the State of Michigan.

The Mammoth Remains Having Been Partially Excavated (in situ)

Down in the hole the skull and tusks emerge.

Down in the hole the skull and tusks emerge.

Picture Credit: ITN

Examination of the teeth indicates that the animal was adult and about forty years of age when it died.  Speculating on how the body came to be under a soya bean field, palaeontologists have explained that the surrounding matrix suggests a still body of water.  This animal could have been hunted by humans, butchered and then placed in a pond to help preserve the meat.  Placing a carcase in water to help preserve it, is believed to have been a relatively common practice amongst the human inhabitants of North America.  The water would perhaps have iced over quite soon after the kill and the cold water and ice would have kept the meat relatively fresh.

A spokesperson from Everything Dinosaur commented:

“Consider the site of this discovery as an early example of a freezer.  Storing resources for use at a future date, planning ahead, is one of the traits associated with our species.  This sizeable beast would have provided a huge amount of food to a group of nomadic hunters”

According to Professor Fisher, the soya bean field discovery represents one of the most complete Woolly Mammoth skeletons ever found in the State.  Once all the bones have been removed, they will be carefully examined and a detailed analysis undertaken.  The scientists will hope to find tell-tale marks in the bone to indicate human butchery.

The Skull with its Partial Tusks Intact is Removed from the Hole

On the surface a ventral view of the skull.

On the surface, a ventral view of the skull.

Picture Credit: ITN

The Professor stated:

“Study of the bones may shed light on when humans arrived in the Americas, a topic of debate amongst archaeologists.”

To read an article about the latest research into Mammoths: Woolly Mammoth Genome is Sequenced

Mapping the Lives of a Population of Dinosaurs

Maiasaura peeblesorum – The Maiasaura Life History Project

Years of excavation at the quarries identified as nesting sites for the Hadrosaur known as Maiasaura (M. peeblesorum) has yielded an immense amount of data.  However, a team of scientists from Montana State University, Oklahoma State, and the Indiana Purdue University have taken the field research in a different direction and used an immense fossil deposit covering over two thousand square metres to report on the largest dinosaur population growth study ever undertaken.

The team’s findings make quite sombre reading for any would-be duck-billed dinosaur (not that they could read, we know).  Mortality rates for animals under twelve months of age were nearly 90%, whilst if you got passed your eighth birthday, the odds were beginning to stack up against you for living much longer.  These dinosaurs lived in tough times.  The numbers might sound frightening but mortality rates in extant antelope and other herbivores on the African savannah, are in some cases very similar.  Predatory dinosaurs probably did not fare any better.

Maiasaura peeblesorum – Model by Safari Ltd

Model of "Good Mother Lizard"

Model of “Good Mother Lizard”

Picture Credit: Everything Dinosaur

Maiasaura peeblesorum

Maiasaura was a large, flat-headed, duck-billed dinosaur that inhabited North America during the Late Cretaceous.  The first fossils of Maiasaura were found in the Badlands of western Montana in 1978, by a team of American scientists led by the famous palaeontologist Jack Horner.  The site the team discovered consisted of a number of nests, eggs, baby Maiasaura, juveniles as well as adult specimens.  The area was renamed “Egg Mountain”.  Approximately, 200 individual specimens have been excavated, providing evidence of the nesting behaviour of dinosaurs.  Published papers on these fossils were amongst the first to put forward the hypothesis that some types of baby dinosaurs were altricial, that is, heavily dependent on their parents for food and protection.  Here was evidence of dinosaurs being raised in nests.

This new research published this week in the journal “Paleobiology” provides the most detailed life history of any dinosaur and has created a framework to which all other dinosaurs can be compared.

The Badlands of Montana – Once Home to Thousands of Dinosaurs

The Badlands of Montana.

The Badlands of Montana.

Picture Credit: Holly Woodward Ballard/Karen Chin

Commenting on the significance of the research, Jack Horner, curator of the Museum of the Rockies and a man synonymous with all things Maiasaura stated:

“This is one of the most important pieces of palaeontology involving MSU [Montana State University] in the past twenty years.  This is a dramatic step forward from studying fossilised creatures as single individuals to understanding their life cycle.  We are moving away from the novelty of a single instance to looking at a population of dinosaurs in the same way we look at populations of animals today.”

The research was led by Holly Woodward Ballard, Assistant Professor of Anatomy at Oklahoma State University, who prior to her appointment to this post, undertook her PhD at Montana State University.  Holly specialises in studying osteohistology (growth patterns of animals preserved in bone tissue) to map population growth dynamics in extinct vertebrates.  This data can then be used to create a model for palaeohistologic inferences, examining how individuals vary within a population, growth rates and survival rates.

To complete the research, the team analysed the fossil bone micro-structure (histology) of fifty Maiasaura tibiae (lower leg bones).  The bone histology reveals aspects of growth that cannot be ascertained by observation of the external structure and shape of the bone.  The histology reveals information such as growth rate, metabolism, age of maturity, and the age at death.

Assistant Professor Woodward Ballard explained:

“Histology is the key to understanding the growth dynamics of extinct animals.  You can only learn so much from a bone by looking at its shape, but the entire growth history of the animal is recorded within the bone.”

To a statistician a sample of just fifty may not sound like much, but to a vertebrate palaeontologist where a species can be known from a single bone or even a single tooth the Maiasaura fossil assemblage from the Badlands of Montana represents an absolute treasure trove of dinosaur fossil material.

The published paper provides an insight into how quickly Maiasaura babies grew up.  It had bird-level growth rates throughout most of its life, its bone tissue most closely resembles that of a modern warm-blooded (endothermic) mammal such as an elk.

The speed of growth might have something to do with the fact that the bigger you got the less chance of you ending up as a meat-eater’s lunch.  Everything Dinosaur has reported previously on a study into the histology of another Hadrosaur, called Hypacrosaurus that showed that these herbivores grew faster than the carnivorous dinosaurs that co-existed with them.

To read more about this study: Duck-Billed Dinosaurs Grew Fast to Avoid Tyrannosaurs

The bone histology also recorded major events in the life of individuals such as the different ages when animals died.

Elizabeth Freedman Fowler, curator of palaeontology at the Great Plains Dinosaur Museum in Malta (Montana), conducted the statistical analysis of the research data, she commented:

“By studying the clues in the bone histology, and looking at patterns in the death assemblage, we found multiple pieces of evidence all supporting the same timing of sexual and skeletal maturity.”

With these dinosaurs, they probably were mature enough to breed within the third year of life and had an average adult body weight of 2,300 kilogrammes in eight years.  Life was tough for these herbivorous dinosaurs, especially the very young or the very old.  The average mortality rate for those less than twelve months of age was 89.9%, for individuals eight years and older it was 44.4%.  These figures sound alarming but most of the garden birds hatched this spring will not survive their first winter.

If a Maiasaura made it through two years, they enjoyed a six-year window of peak physical and reproductive fitness, when the average mortality rate was just 12.7%.

Assistant Professor Woodward Ballard added:

“By looking within the bones and by synthesizing what previous studies revealed, we now know more about the lift history of Maiasaura than any other dinosaur and have the sample size to back up or conclusions.  Our study makes Maiasaura a model organism to which other dinosaur population biology studies will be compared.”

Study Shows Considerable Variation with an Extinct Animal Population

The research also highlighted the extent of individual size variation within an extinct population of animals.  Earlier studies had linked age to the size of dinosaur limb bones, this method may not be that accurate based on this new data.  Histology studies examining a subset of dinosaur bones (such as femora or tibiae) had been carried out before with an assumed age for an animal calculated on the length of these key bones.  The length of the bone may be misleading, it is only by exploring the micro-structure of the bone that age details can be revealed.

Holly outlined how their research challenged the findings of earlier studies:

“Our results suggest you can’t just measure the length of a dinosaur bone and assume it represents an animal of a certain age. Within our sample, there is a lot of variability in the length of the tibia in each age group.  It would be like trying to assign an age to a person based on their height because you know the height and age of someone else.  Histology is the only way to quantify age in dinosaurs.”

Assistant Professor Holly Woodward Ballard at the Maiasaura Dig Site

At the Maiasaura bonebed.

At the Maiasaura bonebed.

Picture Credit: Holly Woodward Ballard/Karen Chin

The Maiasaura Life History Project

The Maiasaura research does not end with the publication of this paper.  This is only one of a series of proposed study areas.  Assistant Professor Woodward Ballard intends to lead a number of annual summer excavations up into the Badlands of Montana to collect more specimens.  The scientists want to keep working on the extensive bonebeds and build up a much more complete picture of the daily lives and struggles of these dinosaurs.

Clearly excited about the opportunity the huge bonebed presents, Holly stated:

“Our study kicks off The Maiasaura Life History Project, which seeks to learn as much as possible about Maiasaura and its environment seventy-six million years ago by continuing to collect and histologically examine fossils from the bonebed, adding statistical strength to the sample.  We plan to examine other skeletal elements and make a histological “map” of Maiasaura, seeing if the different bones in its body grew at different rates, which would allow us to study more aspects of its biology and behaviour.  We also want to better understand the environment in which the Maiasaura lived, including the life histories of other animals in the ecosystem.”

We at Everything Dinosaur wish all those involved in The Maiasaura Life History Project every success and we look forward to reporting on further research in the near future.

Redefining the Neanderthals

Changing Perceptions Towards Homo neanderthalensis

The Gibraltar Museum is holding a special conference at the end of September.  It is in part a celebration of the Museum’s eighty-five year history but it also sets out to re-dress some of the misconceptions about our nearest ancestor, the Neanderthal.  The idea that these hominins were nothing more than blood-thirsty, brutal creatures, a view held as sacrosanct for much of the 20th Century, has now been altered for ever as recent discoveries by palaeontologists and palaeoanthropologists have shed new light on our closest ancestor, one that walked amongst us as recently as 28,000 years ago.

Neanderthal – Our Closest Relative

Research into the genetics of ancient hominids.

A clever and sophisticated species.

High profile speakers and international scientists, all specialists in the study of human evolution, will converge on Gibraltar to discuss how our views have changed in a conference entitled “Redefining the Neanderthals”.

Gibraltar is a very appropriate location to hold such a conference.  It was in Gibraltar that the first Neanderthal skull was found and studied by scientists, although the find (1848), took place before the Neanderthal species was named.  Neanderthal occupation has been identified in at least ten caves in the area, in fact, the Neanderthals who lived on the coastal plain that once existed where the rock of Gibraltar now stands may have been some of the very last of their species.

The Neanderthal caves and the surrounding area has been nominated for World Heritage Status, if these locations are granted such status, it would give the caves the same standing in scientific circles as the Great Barrier Reef, and the Jurassic Coast of Dorset.

The conference will also highlight Gibraltar as an exceptionally important part of the world for Neanderthal studies.  It will run from the 24th to 26th September and invited delegates will be given the opportunity to visit some of the research sites on Sunday the 27th.  Professor Chris Stringer (Natural History Museum, London) will deliver the opening address.  Speakers will come from a number of countries including Spain, Italy, Croatia, Germany and the United States.  Topics to be discussed will include how the Neanderthals were able to exploit raptors and corvids (crows), for a number of purposes.  For example, eagle talons have been used as jewellery (reported from Croatia earlier this summer).

The conference will provide a fresh insight into the Neanderthals, a sophisticated, perfectly adapted hominin whose extinction remains a mystery as there is a growing body of evidence to suggest that these people were smart, strong, capable of language and developed sophisticated cultures.

Why they are gone yet we are here is one of the questions likely to be debated.

If you don’t think the Neanderthals were smart, try catching a crow, or an eagle for that matter!

Homo naledi – New Species of Hominin from South Africa

New Human-Like Species Homo naledi

Researchers from the Evolutionary Studies Institute (University of Witwatersrand), in association with National Geographic, the Department of Science and Technology and the National Research Foundation of South Africa have announced the discovery of a new species of hominin whose fossils were found in an almost inaccessible chamber in a cave system located in the Cradle of Human Kind, on the outskirts of Johannesburg (South Africa).  This new species named Homo naledi shows a mixture of Autstralopithecine traits such as primitive hips and shoulders, but size of the teeth, the slender jaw and wrist bones are remarkably like our own.  Cautious not to refer to this new species as a “missing link” in our own evolution, anthropologists have suggested that the fossils will provide an unprecedented amount of data on how the human family evolved.  As for brain size, the brain of this new species was roughly the size of an extant gorilla.

In total, an astonishing 1,550 bones were recovered from the chamber, these represent fifteen individuals ranging from young children, to adults to the elderly.  The discovery is the largest single collection of hominin fossils found together in the whole of Africa.  Researchers are confident that these fossils will change our ideas about human ancestry.

An Amazing Fossil Hominin Collection (Homo naledi)

The most extensive hominin fossil find from Africa

The most extensive hominin fossil find from Africa

Picture Credit: John Hawks/University of Wisconsin-Madison/University of Witwatersrand

The first set of fossils were discovered in 2013 in a cavern known as the Rising Star (Dinaledi Cave) by Witwatersrand students and volunteer cavers.  The fossils were found in a chamber, some ninety metres from the actual main cave entrance.  The passage to the cavern where the bones lay was so narrow that only small members of the exhibition team could squeeze through to retrieve them.

For Professor Lee Berger (Evolutionary Studies Institute), he had to watch via a video relay, as the students and volunteers carefully removed the bones.

Professor Berger commented:

With almost every bone in the body represented multiple times, Homo naledi is already practically the best-known member of our lineage.”

This new species of hominin was named after the cave in which the fossils were found.  In the local Sesotho language, the caves are known as Dinaledi, the naledi component means “star”.

A Reconstruction of the Face of Homo naledi

Image credit National Geographic

Image credit National Geographic

Picture Credit: National Geographic

A clearly delighted Professor Berger, was astonished to have so many fossils of the same species to study thanks to the meticulous efforts of the team in the cavern to recover the bones.

The professor explained:

“We are going to know everything about this species.  We are going to know when its children were weaned, when they were born, how they developed, the speed at which they developed, the difference between males and females at every developmental stage from infancy, to childhood to teens to how they aged and how they died.”

A Comparison of the Right Hand of H. naledi with the Right Hand of  Homo sapiens

Very similar wrist bones but curved finger bones more like an ape.

Very similar wrist bones but curved finger bones more like an ape.

Picture Credit: Peter Schmid SPL/University of Witwatersrand

The wrist bones are very similar to a modern human’s but the finger bones are more curved, a primitive trait associated with an ancestry of tree climbing (gripping branches).

How Did the Bones Get into the Cavern?

One of the mysteries about the fossil find is how did the bones get into the cavern?  The entrance to the cavern does not seem to have been exposed at the surface and the entrance to the chamber has always been small according to the research team.  There is no evidence of a predator having dragged the bones into its den (no signs of feeding on the bones).  In addition, there is no evidence that the bones were washed into the cave by flood waters, there is an absence of other material in the cave to suggest that this had happened.  The only other bones found are those of small birds and mice, animals that probably wandered into the cave and became trapped.

It has been proposed that this group of human-like creatures fled into the cave for some reason and died there, but an alternative theory, one that has significant implications for our own species and what defines us as “human”, is that the cavern could have been a burial chamber for these hominins.  If a member of the group died, the body was carried into the depths of the cave and purposefully deposited at that location.   This could be evidence of one of the first ever burial sites known from the hominin fossil record.

A Reconstructed skull of Homo naledi

A new species of South African hominin

A new species of South African hominin

Picture Credit:Witwatersrand University

The implications of this hypothesis were succinctly summed up by Professor Berger when he stated:

“We are going to have to contemplate some very deep things about what it is to be human.  Have we been wrong all along about this kind of behaviour that we thought was unique to modern humans?”

If indeed Homo naledi was capable of some form of ritualistic behaviour towards its own dead, what prompted such actions?  Could this hominin have been capable of abstract, symbolic thought – something that has only been associated with much more recent humans, within the last 200,000 years or so.  Is altruistic thinking such as having a sense of bereavement or reverence for the dead an inherited behaviour that runs deep within the human evolutionary line?

How Old are the Fossils?

The age of the fossils is proving a little difficult to assess.  The lack of mammalian bones that are contemporaneous prevents an assessment of age based on a faunal study.  There is a lack of strata to date from within the cave so analysis of any surrounding matrix is not appropriate for this location.  This species could have lived quite recently but it is also possible that Homo naledi could have lived more than three million years ago.  More dating evidence is required to permit scientists to place this new species in the appropriate point in the hominin evolutionary tree.

A note of praise to the brave cavers and student volunteers, most of them women who had to brave a claustrophobic crawl through narrow tunnels before squeezing through one last tight spot to get to the chamber where the bones lay.

Girls Rock!  Some of the Student Volunteers who Helped Remove the Bones

You had to be small to enter the cavern entrance.

You had to be small to enter the cavern entrance.

Picture Credit: Witwatersrand University

The excavation team were nicknamed “underground astronauts”, thanks to all the field team for helping to bring together such a huge amount of data (the paper has just been published in Elife).

The final word should go to Professor Berger, when asked where does Homo naledi fit in with our own evolution, the Professor said:

“What we are seeing is more and more species of creatures that suggests that nature was experimenting with how to evolve humans, thus giving rise to several different types of human-like creatures originating in parallel in different parts of Africa.  Only one line eventually survived to give rise to us.”

Study Suggests Chelonia Evolved from Diapsids

Turtles and their Kin Diapsids Not Anapsids

A study into an ancestral form of the Chelonia (turtles, tortoises and terrapins) has revealed that the skull had a pair of holes in it just behind the eye.  So what, you might say, but this is a big deal, a very big deal, as it means that the history of the reptiles and any subsequent cladograms (family trees), constructed will have to be fundamentally changed.  This new research using the skulls of 260 million-year-old South African Permian reptiles suggests that turtles and their kin are not anapsid reptiles but that this group evolved from diapsids.

Chelonia – Very Ancient Reptiles

Unravelling the history of the Reptilia is a very complicated process.  However, a tenet in helping to establish evolutionary relationships between different types of reptile is the anatomy of their skulls.  It is differences in the number of holes found in the skull behind the eye socket that has helped palaeontologists to understand more about how the first reptiles evolved from amphibians.  Skull anatomy has been used to map the radiation of different forms of reptile, those that led to the birds, crocodiles and the dinosaurs and those who took a different evolutionary line eventually leading to mammals.  Some of this may have to be re-examined in the light of new research conducted by Dr. Gaberiel Bever (Honorary Research Associate at Witwatersrand University and scientist at the New York Institute of Technology) with co-author of the scientific paper, just published in “Nature”, Dr Tyler Lyson of the Denver Museum of Nature and Science.  Three-dimensional models of the skull of the ancestral turtle, a primitive reptile named Eunotosaurus have revealed that this reptile was a diapsid, suggesting that the tortoises and turtles evolved from diapsids and not from what are thought to be more primitive reptiles with anapsid skulls.

Four Basic Types of Reptile Skull

anapsid, synapsid, euryapsid and diapsid

anapsid, synapsid, euryapsid and diapsid

Picture Credit: Before the Ark/BBC

A traditional method of attempting to unravel the phylogeny of early reptiles is to examine the layout of the bones in the skull.  There are four basic skull patterns for reptiles (living and extinct forms):

  • Anapsid – the most simple skull type with the skull bones only having holes for the eyes and the nostrils. Up until this research was published, turtles, tortoises and terrapins were thought to belong to this group.
  • Synapsid – has one hole behind the eye socket on either side of the skull between the squamosal and the postorbital skull bones (sq and po), the lower opening when compared to diapsids.
  • Euryapsid – has one hole behind the eye socket above the squamosal and the postorbital skull bones (sq and po), the upper opening when compared to diapsids.
  • Diapsid – has two holes behind the eye socket on either side of the skull (lower and upper openings in the skull between the squamosal and postorbital bones.

Helping in the research effort involved using CT scans and computer modelling techniques to produce three-dimensional images of the fossil skulls, were Yale University’s Daniel Field and Bhart-Anjan Bhullar (Assistant Professor, Department of Geology & Geophysics).

The fossilised skulls come from the famous Karoo Basin and are assigned to an ancient ancestor of modern turtles called Eunotosaurus africanus, Everything Dinosaur reported on the significance of these fossils in terms of tracing the evolutionary history of the turtle family back in 2013.

To read more about E. africanusHow the Turtle Got Its Shell

Commenting on their research Dr. Gaberiel Bever stated:

“Eunotosaurus is a critical link connecting modern turtles to their evolutionary past.”

Dr. Bever and his co-workers examined high-resolution images created by computer tomography (CT scans).  Their research revealed the complex anatomy of the Permian skulls and supports the theory that animals like Eunotosaurus are indeed the ancestors of today’s tortoises, terrapins and turtles.  Once the skull anatomy had been mapped, the team re-drew the cladogram of the Reptilia based on their findings.

Dr. Bever explained:

“Using imaging technology gave us the opportunity to take the first look inside the skull of Eunotosaurus.  What we found not only illuminates the close relationship of Eunotosaurus to turtles, but also how turtles are related to other modern reptiles.”

A key finding of the study was that Eunotosaurus had a pair of openings set behind the eyes. Eunotosaurus was a diapsid.

The Chelonia Are More Closely Related to Other Reptiles Than Previously Thought

Eunotosaurus a diapsid reptile.

Eunotosaurus a diapsid reptile.

Picture Credit: Witwatersrand University with additional annotation by Everything Dinosaur

This suggests that the ancestors of the turtle lineage were not very primitive anapsids, with skulls similar to those found in amphibians, they were diapsids and therefore the turtle family is more closely related to crocodiles, lizards, snakes, birds and dinosaurs than previously thought.

The holes behind the eye socket served to lighten the skull to help make it more manoeuvrable.  The jaw muscles were able to lengthen and flex to a greater degree, this would have given Eunotosaurus a more powerful and quicker bite than modern tortoises and their kin.

Explaining the significance of this study Dr. Bever stated:

“We can now draw the well-supported and satisfying conclusion that Eunotosaurus is the diapsid turtle.”

In linking turtles to their diapsid ancestry, the skull of Eunotosaurus also reveals how the evidence of that ancestry became obscured during later stages of turtle evolution.

“The skull of Eunotosaurus grows in such a way that its diapsid nature is obvious in juveniles but almost completely obscured in adults.  If that same growth trajectory was accelerated in subsequent generations, then the original diapsid skull of the turtle ancestor would eventually be replaced by an anapsid skull, which is what we find in modern turtles.”

This new study means that the reptile cladogram will have to be re-drawn.  This research helps to cement the phylogenetic relationships between different reptile groups, but the researchers admit that this study is not the end of the matter, merely a beginning.

Witwatersrand University Professor Bruce Rubidge, who has been leading the collaborative effort to explore the rich vertebrate fossil assemblage of the Karoo Basin, explained that although the focus of the research had been on piecing together evidence to outline the diverse fauna of the Middle and Late Permian, their work had implications for studying modern reptiles too.

He stated:

“This is a major step towards understanding the interrelationships of reptiles.  Also of great significance is that Eunotosaurus, which is known only from South Africa, is a critical transitional form in the origin of tortoises and this finding indicates that the tortoise lineage had its origins in Gondwana.”

Dr. Bever summarised the way forward for the research team:

“There is still much we don’t know about the origin of turtles or which of the other diapsid groups form their closest cousin?  What were the ecological conditions that led to the evolution of the turtle’s shell and the anapsid skull?  How much of the deep history of turtle evolution can be discovered by studying the genes and developmental pathway of modern turtles.”

One thing that is for sure, most of the published works on the phylogenetic relationships between the Reptilia (alive and extinct) have just become in need of an update.

“Lucky Find” Puts Welsh Theropod Discovery on a Firm Footing

Fossilised Dinosaur Foot Bones Found on Welsh Beach

Serendipity and palaeontology are often strange bedfellows, but luck does play a part especially when you consider the difficulties in finding very rare and exceptional items such as Early Jurassic dinosaur bones.  Take the example of palaeontology student Sam Davis who has been lucky enough to have been in the right spot at the right time to find the fossilised foot bones of the first meat-eating dinosaur known from Wales.  The bones belong to an, as yet, not scientifically described species of Theropod dinosaur found by brothers Nick and Rob Hanigan in 2014.  The bones come from the Lower Jurassic strata exposed at Lavernock beach (Vale of Glamorgan).

An Illustration of the Newly Discovered Welsh Dinosaur

Significant dinosaur discovery.

Significant dinosaur discovery.

Picture Credit: National Museum of Wales/Bob Nicholls

To read more about the 2014 dinosaur discovery: Welsh Dinosaurs – New Early Jurassic Theropod Discovered

A significant proportion of the skeleton, including skull material, was found by the brothers after spring storms revealed the specimen last year.  However, student Sam Davies decided to visit the beach to explore the fossil location after his tutor explained to him about the geology of the area and the nature of the fossils likely to be found eroding out of the steep cliffs.  Sam duly arrived at Lavernock Point just a few hours after a rock fall had exposed the fossil.  Had he decided to visit the site just a few days later, the fossil specimen would very likely have been washed away by the tide and lost to science forever.

The Foot Bones of the Welsh Theropod Dinosaur

The bones are located on a 20cm slab of rock.

The bones are located on a 20 cm slab of rock.

Picture Credit: National Museum of Wales

Third year student Sam, had visited the beach hoping for inspiration for his third year project as part of his studies at the University of Portsmouth, it looks like he has hit the jackpot with his lucky discovery.  We suspect that Welsh Theropods are going to feature in his individual research project this semester.

Commenting on his lucky fossil find, Sam stated:

“It was pure luck that I found it.  It was just sitting on top of a slab of rock.  It was obvious the fossil was fingers or toes, because there were three in a row, but the first thing that came to mind was that it was some sort of Plesiosaur [marine reptile fossils are occasionally found in this area].”

The fossil has been donated to the National Museum of Wales, joining the rest of the Theropod material.  Sam’s tutor is renowned vertebrate palaeontologist Dr. David Martill, he has been tasked with the job of studying the Welsh fossils and producing a scientific paper on the 200 million year old dinosaur.  Everything Dinosaur expects the paper, along with a name for this three metre long, meat-eater to be published next year.

Sam admits to “jumping up and down like a little boy” when he realised the significance of his discovery.

Set for a Bright Future in Vertebrate Palaeontology

Third year palaeontology student Sam Davies.

Third year palaeontology student Sam Davies.

Picture Credit: BBC News

Dr. Caroline Butler, (Head of Palaeontology, National Museum of Wales) exclaimed:

“The dinosaur found by Nick and Rob Hanigan is the first skeleton of a Theropod found in Wales.  Sam’s find adds to its significance because we can learn more about the animal and how it is related to the dinosaurs that eventually evolved into birds.”

The fossil was actually found some weeks ago, but the announcement of this latest discovery coincides nicely with a television documentary being aired on ITV1 on Monday 31st August with part two the following evening.  The documentary entitled “Dinosaur Britain” explores the rich dinosaur heritage of the British Isles and the Welsh Theropod is featured in the second programme of this two-part documentary.

For information on “Dinosaur Britain”: Dinosaur Britain Scheduled for Bank Holiday Monday

A spokesperson from Everything Dinosaur explained:

“The first dinosaurs to be scientifically studied, were described from fossils found in the British Isles, but even today something like one in twenty of all the known dinosaurs is represented by fossil material discovered in this part of the world.  The finding of the additional Welsh Theropod bones was extremely serendipitous and we wish Sam every success with his studies.”

Here’s one palaeontology student who has helped to put Welsh Theropods on a firmer footing.

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