Discovery of Earliest Known Fossil of a Toothless Bird Announced

The discovery of the oldest known toothless bird has been announced by Chinese scientists.  The evolution of birds and their diversification during the Late Jurassic and Cretaceous is little understood by palaeontologists.  There are very few fossils to study.  Birds with their ability to fly took to forests and wooded areas very early in their evolution, especially with so many small theropod dinosaurs running around, being up in a tree and relatively safe was a good place to be for a bird.  However, in forest environments the potential for fossil preservation is often very poor, so there are only a few fossils of early birds within the fossil record.

An Ancient Duck

The north-eastern Chinese province of Liaoning is the exception with many fine specimens of birds (and feathered dinosaurs) having been unearthed.  This new Liaoning genus, named Zhongjianornis yangi was about the size of a pigeon and like the majority of fossils found in this area, the specimen represents an individual that ended up at the bottom of a lake, covered with fine sediment which was low in oxygen and ultimately this aided preservation as a fossil.  A study of the fossil, the paper of which is due to appear in the scientific journal – Proceedings of the Royal Society B, reveals that this early bird may have been semi-aquatic, a sort of early duck.

Fossil Skeleton

To date only one fossil skeleton has been found, but it is virtually complete and like many of the other Liaoning fossils shows exceptional detail.  This particular bird had a long, pointed snout with toothless jaws, shedding new light on the evolution of that well-known feature of birds – the beak.  The Chinese team have dated this creature to approximately 120 million years ago, Early Cretaceous (Aptian faunal stage), it represents the most primitive toothless bird discovered to date.

Although the earliest known bird Archaeopteryx had a number of reptilian features including needle-like teeth in the jaws, a number of different types of bird soon lost their teeth as the Aves order diversified.  This is an example of parallel evolution, with different types of creature evolving the same solution to a common problem, in this case the need to lose weight so that flight could become more efficient.  This is an example of selective pressure to produce a lighter skeleton to aid flight.

A Replica of an Archaeopteryx Fossil

Archaeopteryx fossil cast. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

This particular primitive bird may have fed on fish, although this is speculation, the pointed snout would have helped it catch them but the lack of teeth may have made holding onto slippery prey difficult.  However, many bird species feed on fish today so this is quite possible.  There was a lot of prey in the lush forests and lakes of the Liaoning region during the Early Cretaceous.  The fossil record from Liaoning is very rich with many types of fish, amphibians, reptiles, mammals, plants and birds known, as well as the dinosaurs.

Commenting on this discovery, palaeontologist Dr Zhonghe Zhou, of the Chinese Academy of Sciences, Beijing, stated:

“Over 30 genera of Early Cretaceous birds have been reported in the last two decades from the Lower Cretaceous of north-eastern China, documenting a burst of avian diversification that followed the appearance of the earliest bird Archaeopteryx”.

This new discovery will add to our knowledge regarding the diversity of early birds.

Dr Zhou added:

“The new material is represented by a nearly complete and articulated skeleton. The new bird displays a combination of features that are unknown in any previously reported taxon; in particular, it represents the most basal avian that had completely lost teeth”.

It is very likely that the vast Liaoning deposits will yield even more strange and wonderful fossils in the future, providing scientists with an insight into life in the Mesozoic.

Visit Everything Dinosaur’s website: Everything Dinosaur.

Evidence Suggests Cave Women not Cave Men were Responsible for Cave Paintings

The contemporary image of a solitary cave man carefully painting an image of the animals he and his fellow hunters intended to catch is being challenged by a new study into European cave art. Cave women played a significant role, according to new research..

Professor Dean Snow and a team of researchers from Pennsylvania State University have compared the hand impressions left by our ancestors on cave walls with those of modern Europeans and concluded that many of the hand prints were from women.  If the prints are female, then it could be suggested that the artworks, too were by the hand of the fairer sex.  The hand print, being a symbolic gesture indicating ownership of the painting or perhaps staking a claim for recognition for their artwork, just as a painter may sign their work today.

Cave Women

Having studied the Palaeolithic paintings in French caves such as Pech Merle in south-western France and the cave at Gargas (French Pyrenees), the American team concluded that even after a “superficial” examination of published photographs there seemed to be plenty of female hands depicted on the cave walls.

Adult male hands are normally much larger in size than adult females, the smaller prints left behind by our ancestors on cave walls could have been made by woman or younger males or females.  Such a revelation could challenge our existing understanding of the role of the sexes in early human settlements.

Professor Snow and his team used measurements of the hands of modern Europeans and compared these to the measurements taken of the hands from the cave walls.  Using ratios between the digits to determine the sex, the team concluded that a number of the prints were female.

Commenting on the digit ratios, Professor Snow stated:

“The very long ring finger, it is a dead giveaway for male hands, a long index finger and a short little finger is very feminine”.

If you give a child a paint tray and ask him or her to make an impression of their hand, they normally place their hand in the paint and then press it down on the paper to make an impression of the hand.  However, cave paintings depicting hands were made very differently.  Hand prints were not used, instead the hand was used as a sort of stencil.

Scientists have suggested two techniques, firstly the hand was placed on the area of wall where the imprint was required and the paint spat out of the mouth to create a stencil affect.  An alternative method of using a straw to blow the pigment-like paint onto the wall has also been proposed.

CollectA Neanderthal Models (Cave Man and Cave Woman)

CollectA Neanderthal models.

To view the CollectA model collection: CollectA Age of Dinosaurs Popular Models.

Many of the cave paintings have been dated to between 40,000 and 20,000 years ago.  If the artwork was made by women, then the current thinking regarding the role of females in cave society will have to be re-examined.  Indeed, the artwork may have had a different purpose than that assumed previously.  Many of the pictures depict oxen, horses and antelope, the sort of animals that our ancestors hunted.  If the artwork was produced by the women of the clan, did they also participate in the actual hunts?  Images of people hunting left on cave walls have always been interpreted as male, but perhaps if the role of women was greater in ancient cave clan society, perhaps they also took part in hunts.

Dinosaur Size Linked to their Lifestyle and Availability of Food

No sooner have papers been published suggesting that the body weights of dinosaurs may have been overestimated, a new report has just come out suggesting that dinosaurs got so big simply because the resources in their environment allowed them to do so.

Recently, the accepted methodology for estimating the mass of dinosaurs has been challenged.  Heavyweight dinosaurs such as Apatosaurus and Diplodocus have had their estimated body weights reduced using a new mathematical formula.  Now zoologists from the University of Florida have published research that indicates that dinosaurs were the “couch potatoes” of the Mesozoic.

To read the article challenging the accepted methods for calculating the weight of dinosaurs: Dinosaurs were “Thinosaurs” – A weighty issue.

Dr McNab and his team have argued that with easy access to abundant food and a sedentary lifestyle dinosaurs were able to grow into the biggest land living animals known in the fossil record.  A number of theories have been put forward suggesting why dinosaurs were able to grow so big.  For example, natural selection may have favoured bigger and bigger animals through predation pressure and the need to fight to secure a mate.  Or being large may have helped dinosaurs regulate their body temperatures, as large animals with a greater surface area to body mass ratio are generally able to maintain a stable body temperature when compared to much smaller creatures.

However, the team from the University of Florida believe that it was the availability of food resources that was the most important factor.

Using a model based on a vertebrate’s energy use, expenditure, mass and eating habits, Dr McNab explained the body size of living and extinct mammals, including baleen whales, an ancient rhinoceros and modern elephants.  He used the example of the larger mass found in some marine mammals which reflect greater resources in their environment.  Developing his argument Dr McNab has stated that the dinosaurs were neither warm or cold-blooded but maintained a stable body temperature somewhere between the warm-blooded mammals and the cold-blooded reptiles of today, thanks to their enormous size.

While Dr McNab said that thermal biology differences are easily seen in small organisms, he suggested dinosaurs were neither cold nor warm blooded but maintained an intermediate temperature between mammals and reptiles, thanks to their size.

According to the American team, herbivorous dinosaurs grew large as their diet of plants was very edible, with later types of dinosaur benefiting from the development of flowering plants (angiosperms) and fruit.  The paper is published in the scientific journal “The Proceedings of the National Academy of Sciences”.

Dr McNab commented:

“Like couch potatoes sitting within easy reach of high calorie foods, the gargantuan size of dinosaurs most likely stems from the abundance of resources available, coupled with low energy expenditures.   Some dinosaurs reached masses that were at least eight times those of the largest, ecologically equivalent terrestrial mammals”.

A Scale Drawing of a Herbivorous Dinosaur – Torosaurus

Picture credit: Everything Dinosaur

The picture shows an approximate size comparison between a person and a Late Cretaceous herbivorous horned dinosaur, a Torosaurus, a close relative of Triceratops.  Could access to lots of plants including fruit have helped these dinosaurs grow so big?

Dr McNab went onto state:

“The factors most responsible for setting the maximal body size of vertebrates are resource quality and quantity, as modified by the mobility of the consumer, and the vertebrate’s rate of energy expenditure”.

This new report is certainly going to raise one or two eyebrows, when extant types of fern and conifer are studied it is clear that they are difficult to digest and lacking in nutrients.  Even angiosperms quickly evolved toxins and other defences to protect themselves from the ravages of large herbivores.  Having to eat particularly difficult to digest food may be a reason in itself why dinosaurs grew so big.  Herbivores needed a huge digestive system to cope with such a diet and the carnivores grew big too, as their prey got gradually bigger and bigger – a sort of plant-eater/meat-eater arms race.

Visit Everything Dinosaur’s website: Everything Dinosaur.

Winton Formation Yields New Dinosaur Species

Western Queensland is once again vying for the attention of palaeontologists with the announcement of the discovery of three new dinosaur species, one theropod and two titanosaurs.  The fossil remains were discovered near the town of Winton, an area that is rapidly becoming a hot spot for Cretaceous dinosaur fossils with a number of exciting discoveries over the last few years.

Three New Dinosaur Species

The town of Winton and the surrounding Mesozoic strata has become the hub of activity for a number of research teams as they strive to unlock secrets about the southern continent’s prehistoric past.  Winton and the Winton Formation has gained a reputation as being one of the best places to go to in the world to find new dinosaurs.

To read an article about the work going on in Winton: Putting Australia on the Palaeontology Map.

To date something like 400 individual dinosaur bones have been removed from the various dig sites, the report on the three new types of dinosaur has been published in the online scientific journal PLoS One (Public Library of Science One).  The scientists claim that the theropod discovered is a member of the Allosauridae and may be a relative of the meat-eating dinosaur known as Neovenator, the remains of which have been found on the Isle of Wight.

A New Theropod Dinosaur

This new allosaur has been named Australovenator wintonensis.  It would have stood over two metres tall on its strong hind legs, and with three, large claws on each powerful hand, this dinosaur would have been a speedy and formidable hunter.  The fossils have been dated to approximately 98 million years ago, to the mid Cretaceous (Albian faunal stage), when Australia was much nearer the south pole than it is today.  The fossils of Australovenator are the most complete meat-eating dinosaur fossils found to date on the continent.

When compared to other land masses, the dinosaur fossil record for Australia is quite sparse, scientists are working hard to “plug the gaps” in their knowledge of Australian dinosaurs as this work will help researchers understand the geographic distribution of certain dinosaur groups and their taxonomic relationships.

Titanosaur Fossils

The fossil site was discovered in 2006 when a single bone was found, after extensive excavation a large amount of fossil material has been unearthed, including this new allosaurid and two new types of titanosaur.  The dinosaurs were nick-named during the excavation and preparation process, a common occurrence in palaeontology.  The Australian song, Waltzing Matilda was composed in the town of Winton in the late 19th Century, so these new dinosaurs acquired nicknames from characters featured in the song.

The ferocious Australovenator was named “Banjo”, the two titanosaurs Diamantinasaurus matildae was called “Matilda” and the second more gracile titanosaur with a longer neck, Wintonotitan wattsi was christened “Clancy”.  The fossils of meat-eating “Banjo” and the herbivore “Matilda” were found in close proximity.  The sediment from which these fossils were removed indicate that this was a lake or to give it a more Australian term a billabong, when these animals met their end.

Images show a scale drawing of the three new types of dinosaurs.  The stocky titanosaur Diamantinasaurus, the larger, although more slender Wintonotitan and the medium sized allosaurid Australovenator.

Perhaps the large herbivore got stuck in the mud and the theropod was attracted to the site in the hope of getting an easy meal but became stuck itself.  Several of these sites, called predator traps have been found in the fossil record.

A team of palaeontologists from Queensland Museum led the excavation, one of the scientists, Scott Hocknull commented on the discovery of the allosaurid theropod stating:

“It [Australovenator] was the cheetah of its time, light and agile.  It could run down most prey with ease over open ground “.

He went onto say how important these new finds were, and how as a result of the new discoveries, Australia was firmly on the “palaeontology map”.

A Model of the Australian theropod dinosaur Australovenator

The CollectA Australovenator replica.

The picture (above) shows a model of the Australian theropod dinosaur Australovenator.  This model is part of the CollectA Age of Dinosaurs Prehistoric Life series: CollectA Age of Dinosaurs Prehistoric Life Models.

Professor Rod Wells from the School of Biological Sciences at Flinders University, South Australia, added:

“Australia is the exciting new frontier in vertebrate palaeontology.  Scott Hocknull and his team have opened a new window on the dinosaur fauna of a 110 million-year-old portion of the world that remains largely unexplored, indeed a unique Australian fossil heritage”.

The announcement of the discovery was made at the Australian Age of Dinosaurs Museum in Winton, Queensland.  Scientists expect to find many more dinosaurs and other prehistoric animal remains in the area, helping to build up a picture of the ancient Australian outback.

Getting under the Skin of the Dinosaur Mummy – Dakota

A team of scientists led by researchers from the University of Manchester, England, have identified preserved organic molecules in the skin of a dinosaur (dinosaur mummy) that died approximately 66 million years ago.

Dinosaur Mummy

The beautifully preserved fossil of a large, herbivorous duck-billed dinosaur, a hadrosaurine (Edmontosaurus) has been the subject of a National Geographic documentary as the scientists tried to understand what processes had taken place leading to such detailed preservation.

Dinosaur bones are rare, well preserved ones are exceptionally rare and for some palaeontologists the discovery of fossilised bones in association with each other or bones in articulation are the find of a life-time.  However, the discovery of “Dakota” by Tyler Lyson, a young research undergraduate, may prove to be one of the most significant finds in palaeontology.  This dinosaur has much of its skeleton preserved but also, skin, ligaments, tendons and now it has been revealed that some of the organic materials in the skin tissues are present in the fossil as well.

To read more about the duck-billed dinosaur called “Dakota”:

Dinosaur Mummy discovery: Dinosaur Mummy Unlocks Duck-Billed Dinosaur Secrets.

Update on Dakota: Update on Dakota (March 2008).

In a paper published in the prestigious scientific journal Proceedings of the Royal Society B, the team report that the dinosaur’s soft tissues were prevented from decay as it was buried quickly by fine sediments and the fossil was sealed in a mineral cast.  The lack of oxygen helped the preservation process as the soft tissues reacted with the minerals in the sediment to form a kind of protective seal around parts of the fossil leading to this remarkable state of preservation.

Traces of Organic Material

Traces of the original organic matter of the dinosaur are mixed up with the minerals.  The fossil contains microscopic cell-like structures although the proteins that made them have long since decayed.

Dr Phil Manning, Senior Lecturer in Palaeontology and Research Fellow at the Manchester University’s School of Earth, Atmospheric and Environmental Sciences had hinted that “Dakota” may yield some amazing fossil evidence, the like of which has never been seen before in a dinosaur.

An array of advanced and sophisticated techniques were employed by the researchers to test and cross-examine the data they were producing.  For example, the mummified dinosaur reveals two distinct skin layers, a similar composition to that of birds and crocodiles, the closest living relatives to dinosaurs.  The skin of Dakota seems to consist of two distinct layers; a surface epidermis and then underneath a deeper dermis layer made up of dense connective tissue.

Commenting on this research, Dr Manning stated:

“You’re looking at cell-like structures: you slice through this and you’re looking at the cell structure of dinosaur skin.  That is absolutely gobsmacking”.

Photographs show the fossilised skin of the hadrosaurine beginning to emerge from its sandstone casing, the brush is for scale, it is one of the tools used by palaeontologists to remove fine particles carefully from around a fossil.

Pictures reveal a part of the fossilised skin, this picture was taken when Dakota was still in the ground.  Although the proteins that made up the duck-billed dinosaur’s skin have decayed, the amino acids, the building blocks that make up the proteins could still be detected.

Dr Manning went onto state:

“We’re looking at the altered products of proteins from the skin of this animal, locked within the three dimensional mineralised skin”.

These findings regarding the structure of the dinosaur’s skin and its similarities to extant relatives is what Dr Manning refers to as “clean science”.

Preserved Organic Materials in Dinosaur Skin Tissue

Analysis of the skin molecules.

Picture credit: University of Manchester/Dr Phil Manning

“If you’ve got a hypothesis and you can’t test it, it remains a hypothesis.  Now we’ve had an exceptionally preserved dinosaur which has allowed us to ask that question and answer it for the first time”.

Studies of the skin from across the fossil show that the skin was thinner toward the flanks, between the tail and the hips, where other hadrosaur fossils have shown bite marks. Dr Manning said that region may have been the dinosaur’s “Achilles heel”.  The thickness of the animal’s hide and its relationship to bite marks found in other hadrosaur fossils  may provide evidence of the attack strategies of predatory dinosaurs such as the tyrannosaurs

Dr Manning commented:

“If you understand the distribution of these structures in the skin of a prey animal, you can understand something about predator-prey interactions, and it might explain some of the Hadrosaur fossils we see with these bite marks”.

The presence of skin and tissue may also help scientists accurately estimate the weight of this dinosaur.  Recently, new research has been published from teams in Germany and the USA questioning the accepted mathematical formulae that have been used to calculate the weight of extinct animals.  With such a superbly preserved specimen, more data on the mass of dinosaurs can be gathered and this should give more reliable results than estimating body mass from skeletal remains only.

To read more about the controversy over the weight of dinosaurs: Dinosaurs were “Thinosaurs” – A weighty issue.

Derek Briggs, the Director of the Peabody Museum of Natural History at Yale, praised the thoroughness of the work, stating that this research was an important step in elucidating the mechanism by which such soft tissues could be preserved.

“One can’t be certain, but I suspect that in many cases these kinds of skin impressions have gone unnoticed and people have gone after the skeleton, which is of course what you’d expect to be preserved”.

If conditions are right then a remarkable state of preservation can occur and giving the rather zealous way in which dinosaur fossils were collected in the late 19th Century a lot of valuable information could have been lost as collectors tried to find the most complete and best preserved fossilised bones for display.

“This kind of discovery just demonstrates very clearly that soft tissue does survive, that the processes involved are unusual but not absolutely extraordinary – so there’s no reason why this kind of material won’t be discovered again”.

Dr Manning said that studies on Dakota were continuing apace on a fossil he described as a pleasure to work with.   There had been difficulties scanning the two huge sandstone blocks that the dinosaur was removed from the dinosaur’s North Dakota site, after all they weighed several tonnes.

“Whereas most of us have to deal with disjointed sentences and occasional fractured words to reconstruct the volumes of the fossil record, you’ve got a whole chapter lying there and you can flick through the pages at your leisure”.

For models of duck-billed dinosaurs such as Edmontosaurus visit Everything Dinosaur’s award-winning website and take a look at the CollectA Deluxe prehistoric animal range.