New Evidence to Support Gastornis was a Herbivore

When the BBC decided to follow up their ground-breaking television series “Walking with Dinosaurs” by exploring the weird and wonderful animals that survived the Cretaceous mass extinction and went onto dominate life in the Cenozoic, they needed a spectacular animal to feature in the first episode of the new series.  Enter Gastornis, a giant, flightless bird that featured in the opening episode of  “Walking with Beasts”.

“Terror Bird”

This near six foot tall giant bird was depicted as an apex predator stalking the steamy jungles of what was to become Germany.  In the publicity material to promote the six programmes, Gastornis with its huge, powerful beak featured prominently, here was a “terror bird” from a time when birds ate horses.  An attack by a female Gastornis on a Propalaeotherium (an ancient ancestor of modern horses), was vividly depicted.  However, over recent years a growing body of evidence has been presented which suggests this big bird does not deserve its ferocious reputation.

An Illustration of the Giant Bird Gastornis

Not so terrible after all?

Picture credit: Everything Dinosaur

Gastornis/Diatryma

Recently, Everything Dinosaur reported on research carried out by scientists at Western Washington University (United States).  The researchers had studied the footprints, believed to have been made by a Gastornis/Diatryma creature.  The absence of talons and the short stride length led them to conclude that this “terror bird” reputation may be undeserved.

To read more about this study: Not so Terrible Terror Bird.

Much of the reputation of these Palaeocene and Eocene giant birds has been  implied after comparative studies with the Phorusrhacidae group of birds.  Scientists in Germany have added weight to the vegetarian Gastornis/Diatryma debate by presenting a new paper that suggests these birds were essentially herbivores.  Dr Thomas Tuetkin from the University of Bonn (Germany) in collaboration with Dr Stephen Galer, Dr Meinoff Hellmund and Petra Held presented an analysis of bone isotopes from a Gastornis skeleton.  The paper was presented during a session of the Goldschmidt Conference held in Florence, Italy.

Dr Tuetkin Pictured Next to a Model of Gastornis

Gastornis a vegetarian?

Picture credit: Dr Tuetkin (Bonn University)

Gastornis

Commenting on the study, lead researcher Dr Tuetkin stated:

“The terror bird was thought to have used its huge beak to grab and break the neck of its prey, which is supported by biomechanical modelling of its bite force.  It lived after the dinosaurs became extinct and at a time when mammals were at an early stage of evolution and relatively small; thus, the terror bird was thought to have been a top predator at that time on land.”

Isotope Composition

The research team examined the calcium isotope composition contained within the fossilised bones of a Gastornis specimen from a coal mine in the Geisel Valley region of central Germany.  The calcium isotope analysis permitted the team to learn what proportion of the bird’s diet was plant or animal based.  The Gastornis data was then compared to a number of extinct and extant species and the German based team were able to conclude that the calcium isotope composition was similar to that found in herbivorous mammals and dinosaurs.

A Drawing of the Skeleton of Gastornis/Diatryma

Scale bar = 1 metre

Picture credit: Bonn University

Studying Tooth Enamel

Dr Tuetkin added:

“Tooth enamel preserves original geochemical signatures much better than bone, but since Gastornis didn’t have any teeth, we’ve had to work with their bones to do our calcium isotope assay.  Because calcium is a major proportion of bone, around 40% by weight, its composition is unlikely to have been affected much by fossilisation.  However, we want to be absolutely confident in our findings by analysing known herbivores and carnivores using fossilised bone from the same site and the same time period.  This will give us an appropriate reference frame for the terror bird values.”

Team members at Everything Dinosaur have been explaining the latest research regarding the likes of Gastornis to visitors at the Beacon Museum’s exhibition (Whitehaven).  The Beacon Museum is holding  an exhibition into life after the dinosaurs and on certain, special weekends, Everything Dinosaur team members have been invited along to answer questions and help the public to understand more about the amazing birds and mammals that evolved after the dinosaurs died out.  Everything Dinosaur will be making one more appearance at the Beacon Museum, catch up with the team on the weekend of 26th/27th October.

To view models and replicas of Cenozoic animals: Wild Safari Dinos and Prehistoric Animal Models.

Ancient Fossils from New Guinea Help Scientists to Understand Distribution of Prehistoric Sea Cows

A gap in Australasia’s marine evolutionary record has been filled by a group of sea cow fossils recently identified by museum scientists as the oldest ever found in the region.  The 12-million-year-old fossils were discovered in a cave under the remote central highlands of New Guinea more than 30 years ago, but remained unstudied.  Last year, they were rediscovered in a museum drawer by scientists from Museum Victoria and the Smithsonian Institution, who immediately found the fossils curious.

Australian Sea Cow

Examples of the Fossil Material Discovered in the Cave (Vertebrae)

Picture credit: Dr Erich Fitzgerald

Dr Erich Fitzgerald, Museum of Victoria’s Senior Curator of Vertebrate Palaeontology stated:

“Until now, Australasia didn’t have a particularly ancient fossil record of sea cows, the group of marine mammals that includes our living dugongs.  The records only went back some five million years.  Elsewhere in Asia, sea cow fossils are found in much older rocks, so it was always a mystery as to why the fossils hadn’t been found in this part of the world.  Now, with this one discovery, we’ve more than doubled the length of their evolutionary history in Australasian seas.”

A Vital Perspective

Dr Fitzgerald says the fossils provide a vital perspective on the relationship modern sea cows have with Australia’s northern marine ecosystems.

He went onto add:

“Modern-day dugongs are major consumers of sea-grass, and, by doing so, have a tremendous impact on the structure of the ecosystem.  They participate in a delicate balancing act: their feeding allows diversity in sea-grass and animal species that would otherwise be lacking.”

Studying the Fossils

Until this drawer of fossils was studied, it had been thought that sea cows were fairly recent arrivals in Australasian waters and that these grazers and their relationship with sea-grass ecosystems around Australian waters was also recent.   This new research suggests that these gentle giants have been an important part of Australasia’s marine ecosystems for at least twelve million years and that their role in the long-term health of these environments may be very significant.

Everything Dinosaur is grateful for the Museum Victoria for their assistance in compiling this news story.

For models and replicas of prehistoric animals from Australia and elsewhere in the world: CollectA Age of Dinosaurs Popular Models.

Fossilised Eggs and Large Dinosaur Bones Discovered

Sources at the Institute of Vertebrate Palaeontology and Palaeoanthropology (IVPP) in Beijing, China have reported the discovery of a large number of dinosaur fossils at a site in Laiyang City, in Shandong Province (East China). Over 130 fossils including fossilised egg fragments and large dinosaur bones were unearthed at an excavation adjacent to the village of Jingangko.

Dinosaur Fossils

Fossils were first discovered at the site back in 2010 and palaeontologists working for the IVPP have stated that many of the fossils are in an excellent state of preservation.  Field workers have sealed off the fossils and their exposed matrix with gypsum to protect them before the site can be properly mapped and formal excavation work begun.

Wang Xiaolin, a researcher with the Institute and the scientist in charge of this site declared:

“Most of the fossils are relatively intact, and this is favourable for assembly of a complete dinosaur skeleton.”

Fossilised Bones

Amongst the many fossilised bones the researchers have already recovered is a sixty centimetre long humerus (upper arm bone).  The strata is particularly rich in fossil vertebrates and this latest excavation is one of a number going on in the area as palaeontologists have already unearthed many dinosaur fossils from at least twenty different layers of strata.  Two years ago, the Chinese state set up the Laiyang region as a national park for dinosaur fossil remains.

Great Wealth of Dinosaur Fossils in Eastern China

The enormous amount of dinosaur fossils in Eastern China.

Picture credit: Institute of Vertebrate Palaeontology and Palaeoanthropology

The picture above shows acclaimed Chinese palaeontologist Xing Xu amongst a bone bed of hadrosaur fossils.

Hadrosaur Fossils

Shandong Province has been regarded as one of the most important dinosaur sites discovered in the last one hundred years or so.  A number of important discoveries have been made, including a new genus of tyrannosaurid and in 2010, Chinese scientists uncovered the fossilised remains of a new genus of large horned dinosaur which was named Sinoceratops zhuchengensis.

To read more about this discovery: New Genus of Chinese Ceratopsid Discovered.

PNSO have created a wondeful Sinoceratops figure. To view the extensive PNSO range: PNSO Age of Dinosaurs – Models and Figures.

Estimating the Size of Leedsichthys

Regarded by many scientists as possibly the largest fish of all time, the filter-feeding teleost Leedsichthys is known from just a few fragmentary remains.  With a skeleton made from cartilage, a material that has a poor preservation potential, scientists have struggled for more than a century to try to piece together data on this immense bony fish.  The specific name for Leedsichthys is L. problematicus, which reflects the problems palaeontologists have had in interpreting the fossil evidence.  After all, it was once suggested that fossils found in eastern England and now ascribed to Leedsichthys belonged to an armoured dinosaur.

Leedsichthys problematicus

A new study carried out by scientists at the University of Bristol in collaboration with the University of Kunming in China have estimated the growth rates of these Jurassic creatures.  The research indicates that these animals ranged in size from 12 metres to 16 metres when fully grown.  At the top end of this range, Leedsichthys is indeed capable of claiming the title of the largest, bony fish of all time.  The animals that occupy a similar niche in today’s marine environment are also of an impressive size, filter feeders such as the Baleen whales, manta rays as well as basking and whale sharks.

There has been a lot of debate about just how big Leedsichthys actually was, to read an earlier article: Leedsichthys Subjected to Fish Shrink Ray.

Professor Jeff Liston a member of the research team that reviewed the known Leedsichthys fossil material stated:

“Leedsichthys skeletons preserve poorly, often only as isolated fragments, so previous size estimates were largely historical arm-waving exercises.  We looked at a wide range of specimens, not just the bones but also their internal growth structures – similar to the growth rings in trees – to get some idea about the ages of these animals as well as their estimated sizes.”

The Giant Filter-Feeder Leedsichthys

Giant filter feeder of the Jurassic

Picture credit: Robert Nicholls

Cartilaginous Back Bone Preserved

Occasionally, elements of the cartilaginous back bone are preserved.  These parts of the skeleton can become mineralised and thus have a better chance of surviving the fossilisation process.  Just like in shark species today, the discs that make up the back bone can show preserved internal rings that permit scientists to estimate the age of the animal when it died and how quickly it grew.  Using data from documented Leedsichthys fossil finds, including evidence from a recently discovered specimen found near Peterborough (East Anglia, England), the team estimated that an, adult fish of 8-9 metres would be around twenty years of age.  Lengths in excess of 16 metres would have been reached when the animal was around 38 years of age.

For models and replicas of prehistoric fish and other ancient creatures: PNSO Age of Dinosaurs Replicas and Scale Models.

Scientists are not sure how long these animals lived, but it has been suggested that these leviathans could leave for forty years or more.

Research Project

The project began in Glasgow with a review of the remains of the giant Jurassic fish Leedsichthys, in conjunction with the excavation of a new specimen of this creature (the Peterborough specimen). Professor Liston, who ran the excavation in Peterborough, wanted to explore an anomaly as before Leedsichthys, most vertebrate suspension feeders did not grow much larger than half a metre in length.  It seems sometime around 165 million years ago, the ocean’s ecosystem changed, which permitted these large vertebrates to evolve.

Professor Liston stated:

“The existence of these large suspension-feeding fish at this time is highly significant as it would seem to be clear evidence of a major change in plankton populations in the oceans of Jurassic Earth: a ‘smoking gun’ that something new, widespread and highly edible was around, possibly related to the first appearance of small crustaceans called copepods.  This has implications for our understanding of biological productivity in modern oceans, and how that productivity has changed over time.”

The researchers also looked at specialist structures on the gills as a means of how Leedsichthys grew so large.

Professor Liston added:

“One of the truly fascinating aspects of this fish as a suspension feeder, is that it seems to have developed a unique mesh structure on its gills to help it extract plankton as the seawater passed through its mouth.  Extremely delicate and rarely-preserved, it resembles the honeycomb pattern in a bee-hive.  It functioned like a trawler’s net to trap plankton, and obviously was very effective, given the large sizes this animal achieved.  This mesh structure is very different to what we see in today’s suspension-feeding fish and whales.  It had a unique way of solving a similar problem.”

A Filter Feeding Giant

Filter feeding seems to have enabled Leedsichthys to grow to a very large size.  Its bulk would have made it almost invulnerable to attack, very helpful when you shared the sea with predators such as pliosaurs, plesiosaurs and marine crocodiles.

Leedsichthys

Professor Liston had been involved in a related project reported upon by Everything Dinosaur in 2010.  The fossil record is so poor for cartilaginous fish that there was a huge gap in the fossil record from the likes of the Middle Jurassic Leedsichthys to the filter feeders known from the Cenozoic.  A discovery of a giant, filter-feeding fish of the Late Cretaceous (Bonnerichthys) helped plug what was a 100 million year gap in the fossil evidence.

To read more about Bonnerichthys: Filter-Feeder from the Western Interior Seaway (Cretaceous).