Brontosaurus coming back to dinosaur science?


Brontosaurus as researchers imagined it in the late 1800s, on a chocolate wrapper. Photograph: Picasa

From daily The Guardian in Britain:

Brontosaurus is back! New analysis suggests genus might be resurrected

Despite its relegation to a subset of the Apatosaurus family in 1903, new research suggests that the Brontosaurus is distinct enough to be a genus

Hannah Devlin, science correspondent

Tuesday 7 April 2015 12.52 BST

The Brontosaurus is famous for having been resigned to extinction twice – the second time when scientists concluded that it was another long-necked dinosaur that had been misclassified.

Now, the “thunder lizard” looks set to make a comeback, after a new analysis suggests that Brontosaurus skeletons really are distinct enough to warrant their own genus.

The scientists behind the work hope the findings will trigger the resurrection of the Brontosaurus genus, which was discarded by most academics more than 100 years ago.

“It’s a nice example of how science works. A new finding can overturn more than 100 years of beliefs,” said Emanuel Tschopp, who led the study at the Nova University in Lisbon.

The discovery of Brontosaurus dates back to the so-called “Bone Wars”, a period in the US when a wealth of new dinosaur fossils were being discovered and rival palaeontologists were racing to name as many as possible. Brontosaurus was hastily named in 1870, a few years after another bulky long-necked specimen, the Apatosaurus (deceptive lizard), was discovered.

By 1903, it had been relegated to a subset of the Apatosaurus family, but the dinosaur has lived on as a mainstay in popular culture. “It’s probably because when it was found it was one of the first really complete long-necked dinosaurs,” said Tschopp. “It also just has a really good name.”

The argument for bringing back the iconic title is entirely objective, the scientists say. “Although I was excited when I found it might be the case,” he added.

Professor Paul Barrett, a senior dinosaur researcher at the Natural History Museum in London, said he is ready to re-adopt the Brontosaurus title, based on the findings. “It’s the biggest study on this family, they martial a lot of evidence and make a very good case,” he said.

“It’s taken us a long time to convince people that we shouldn’t be using the name ‘Brontosaurus’,” he added. “Just as we’ve got to that point, it looks like we’re going to have to turn around and say ‘Actually, it’s alright again’.”

Brian Switek, author of My Beloved Brontosaurus and amateur palaeontologist based in Utah, said: “I want to believe, but I’m not sure the Brontosaurus is here to stay just yet.”

The problem, he said, is that there is no standard way of picking which anatomical traits are significant, meaning there will always be a degree of subjectivity in drawing up distinctions between closely related species. Done a different way, another analysis could easily sink Brontosaurus back into the Apatosaurus genus. The question is unlikely to be definitively agreed, Switek predicts, without the discovery of new fossils, in particular a Brontosaurus skull.

The latest analysis focussed on the Diplodocidae clade, the family containing Diplodocus, Apatosaurus and several other long-necked specimens.

The Diplodocidae dinosaurs lived from 170 to 130 million years ago, and are distinguished by their short legs (they are sometimes dubbed the “dachshund” of dinosaurs) and incredible length. The average length of an Apatosaurus was 22m, but a related species, Supersaurus, was thought to have reached 34m head to tail.

The scientists analysed around 50 skeletons and measured around 500 anatomical traits to assess the hierarchy of differences within the family. Statistically, they found there were two main groups: one containing more slender species, such as Diplodocus, and a second containing the bulkier Apatosaurus. Within the Apatosaurus group, though, there were further considerable distinctions, including the fact that Apatosaurus had a thicker neck, according to the PeerJ report.

“The differences we found between Brontosaurus and Apatosaurus were at least as numerous as the ones between other closely related genera, and much more than what you normally find between species,” said Roger Benson, a co-author from the University of Oxford.

The distinction between species and genera is without clear rules, but should at least be self-consistent, the authors argue.

Unlike with living species, there is no official procedure for creating a new genus or reinstating an old one, and whether Brontosaurus makes a comeback will depend on popular consensus within the community. “Other researchers will now need to test the evidence for resuscitating Brontosaurus,” said Tschopp.

The authors said the research was only possible due to the recent discovery of several new dinosaurs similar to both Apatosaurus and Brontosaurus, which made it possible to undertake a detailed investigation of how different they actually were.

“Our research would not have been possible at this level of detail 15 or more years ago,” said Tschopp. “In fact, until very recently, the claim that Brontosaurus was the same as Apatosaurus was completely reasonable, based on the knowledge we had.”

Irrespective of the scientific outcome, the dinosaur is likely to live on in the popular imagination. “The ghost of Brontosaurus will always be with us,” said Switek.

See also here.

Very long-necked dinosaur discovered in China


This 2014 video is called Finding Dinosaur Documentary.

By Jacqueline Howard:

New Dinosaur Species Discovered In China Takes Long Necks To A Whole New Level

01/29/2015 2:59 pm EST

A new dinosaur species discovered in China is being called “extreme”–and for good reason. The dino’s neck is so long that it makes up more than half of the creature’s huge 49-foot-long body.

The dinosaur–dubbed Qijianglong guokr, or “dragon of Qijiang“–is believed to have roamed Asia about 160 million years ago in the Late Jurassic Period. It was identified by skull and vertebrae fossils unearthed in 2006 by construction workers near Quiang City in the southern part of the country.

“If you imagine a big animal that is half neck, you can see that evolution can do quite extraordinary things,” Tetsuto Miyashita, a Ph.D. student at the University of Alberta in Canada and a member of the team of scientists who identified the dinosaur, said in a written statement. “Qijianglong shows that long-necked dinosaurs diversified in unique ways in Asia during Jurassic times—something very special was going on in that continent.”

Qijianglong is believed to belong to mamenchisauridae, a family of dinosaurs known for extremely long necks. But unlike most mamenchisaurids, Qijianglong had vertebrae that were hollow and so tightly linked that the dinosaur’s neck is believed to have been stiff like a construction crane.

A paper describing the newly identified dinosaur was published online in the Journal of Vertebrate Paleontology on Jan. 26, 2015.

Purgatorius, world’s oldest primate?


This video says about itself:

PurgatoriusExtinction of the Dinosaurs

29 November 2014

Purgatorius and the extinction of the dinosaurs.

Scenes from Animal Planet‘s Animal Armageddon.

From Proceedings of the National Academy of Sciences of the United States of America:

Oldest known euarchontan tarsals and affinities of Paleocene Purgatorius to Primates

Significance

Purgatorius has been considered a plausible ancestor for primates since it was discovered, but this fossil mammal has been known only from teeth and jaw fragments. We attribute to Purgatorius the first (to our knowledge) nondental remains (ankle bones) which were discovered in the same ∼65-million-year-old deposits as dentitions of this putative primate. This attribution is based mainly on size and unique anatomical specializations known among living euarchontan mammals (primates, treeshrews, colugos) and fossil plesiadapiforms.

Results of phylogenetic analyses that incorporate new data from these fossils support Purgatorius as the geologically oldest known primate. These recently discovered tarsals have specialized features for mobility and provide the oldest fossil evidence that suggests arboreality played a key role in earliest primate evolution.

Abstract

Earliest Paleocene Purgatorius often is regarded as the geologically oldest primate, but it has been known only from fossilized dentitions since it was first described half a century ago. The dentition of Purgatorius is more primitive than those of all known living and fossil primates, leading some researchers to suggest that it lies near the ancestry of all other primates; however, others have questioned its affinities to primates or even to placental mammals.

Here we report the first (to our knowledge) nondental remains (tarsal bones) attributed to Purgatorius from the same earliest Paleocene deposits that have yielded numerous fossil dentitions of this poorly known mammal. Three independent phylogenetic analyses that incorporate new data from these fossils support primate affinities of Purgatorius among euarchontan mammals (primates, treeshrews, and colugos).

Astragali and calcanei attributed to Purgatorius indicate a mobile ankle typical of arboreal euarchontan mammals generally and of Paleocene and Eocene plesiadapiforms specifically and provide the earliest fossil evidence of arboreality in primates and other euarchontan mammals. Postcranial specializations for arboreality in the earliest primates likely played a key role in the evolutionary success of this mammalian radiation in the Paleocene.

Utahraptor dinosaur mass grave discovery


This video from the USA says about itself:

Gastonia vs Utahraptor– Epic!

This fight was a real fight that was recorded in bones! The Utahraptor was attacking such an armed dinosaur cause it was about to die by lack of food during a drought. And in the end both animals died, the Gastonia died by its wounds which the Utahraptor inflicted on its belly and legs. And the Gastonia died only 10 feet away after walking from the dead Utahraptor.

From the Washington Post in the USA:

Fossil treasure trove in quicksand reveals ancient dinosaur death trap

By Rachel Feltman

January 7 at 9:35 AM

Reports of what looked like a human arm brought Utah state paleontologist James Kirkland to a particular sandstone hill in 2001. But it turned out that his graduate student had actually found something entirely different — a veritable mass grave of Utahraptor dinosaurs. Now they’ve found the remains of six individual dinosaurs, and there may still be more inside of the 9-ton sandstone block they’re excavating.

That “arm” was actually a foot, and the fossil bits just kept coming. The site is now the largest find ever for this particular species, which was a large, feathered cousin to the more familiar Velociraptor. It seems that these unfortunate raptors were trapped in quicksand — sand so heavy with water that it loses much of the friction between its grains. Quicksand isn’t actually the deathtrap for humans that cinema would have us believe, but for a frightened animal who couldn’t gain purchase, it might have meant suffocation or slow starvation — or simply getting stuck until a bigger predator arrived to finish the job.

Brian Switek for National Geographic reports that a plant-eating dinosaur was found at the site, too, which could mean that the raptors all died at the same time while hunting the trapped creature. That would be exciting, because despite their depiction as pack hunters in the “Jurassic Park” films, we don’t have much evidence about whether dinosaurs like these came in droves or hunted solo.

If the researchers can show that the raptors grew tangled up together as they struggled to get free, or find evidence that the same weather patterns affected their bones when they died, it would add weight to the notion that raptors liked to rumble in gangs.

You can see clips of the excavation in progress over at National Geographic.

Tyrannosaurs video


This video is called Top 10 Largest Tyrannosaurs.

Sweden’s first carnivorous dinosaur discovery


This video says about itself:

5 August 2013

Dinosaurs that has been found in Sweden, Greenland, Denmark and the islands of Svalbard.

I also include amphibians, marine reptiles, birds, crocodiles & pterosaurs that lived during the same time as the dinosaurs.

Fortunately, not all news from Sweden is about racist criminals.

From The Local in Sweden:

Jurassic Park fan finds rare dinosaur remains

Published: 02 Jan 2015 06:42 GMT+01:00

A high school student from southern Sweden who discovered the remains of Sweden’s first known carnivorous dinosaur has been speaking about his discovery.

Clarence Lagerstam, who lives in Kristianstad in Skåne found a small piece of bone when he was searching in an area popular with fish and reptile fossil hunters.

“I did not think there would be more, but then I found more smaller fragments and I became more and more excited,” he told Swedish news network SVT.

Experts believe the bones are the remains of a large carnivorous dinosaur that lived on what is now Swedish soil around 80 million years ago when the region had a warm climate, similar to that in the Mediterranean today.

Lagerstam has kept his finding in a black cardboard box, wrapped in paper towels, but has opened it several times this week to show off what he calls his “dream” finding to the Swedish media.

Johan Lindgren, a paleontologist and researcher at nearby Lund University says it is “fantastic” that the schoolboy made the finding in an area where experts have been searching for fossils for 150 years.

“You can never stop being fascinated by what is actually out there in the Swedish soil,” he told SVT.

Lagerstram says he first became interested in fossils and dinosaurs when he watched the movie Jurassic Park and plans to continue with his interest.

“It’s a great feeling to be able to read about ancient ecosystems and to learn what prehistoric animals looked like, how they lived and how they interacted with their environment”.

Sauropod dinosaurs’ neck postures, new research


This video from the USA says about itself:

Scientists reconstruct giant sauropod dinosaur – by Scientific American

22 apr. 2011

A new exhibit at the American Museum of Natural History features a 60-foot model of the dinosaur named Mamenchisaurus. The model reveals what we know and don’t know about these plant-eating giants.

From PeerJ:

Quantifying the effect of intervertebral cartilage on neutral posture in the necks of sauropod dinosaurs

Michael P. Taylor​

December 23, 2014

Abstract

Attempts to reconstruct the neutral neck posture of sauropod dinosaurs, or indeed any tetrapod, are doomed to failure when based only on the geometry of the bony cervical vertebrae. The thickness of the articular cartilage between the centra of adjacent vertebrae affects posture. It extends (raises) the neck by an amount roughly proportional to the thickness of the cartilage. It is possible to quantify the angle of extension at an intervertebral joint: it is roughly equal, in radians, to the cartilage thickness divided by the height of the zygapophyseal facets over the centre of rotation.

Applying this formula to published measurements of well-known sauropod specimens suggests that if the thickness of cartilage were equal to 4.5%, 10% or 18% of centrum length, the neutral pose of the Apatosaurus louisae holotype CM 3018 would be extended by an average of 5.5, 11.8 or 21.2 degrees, respectively, at each intervertebral joint. For the Diplodocus carnegii holotype CM 84, the corresponding angles of additional extension are even greater: 8.4, 18.6 or 33.3 degrees. The cartilaginous neutral postures (CNPs) calculated for 10% cartilage—the most reasonable estimate—appear outlandish. But it must be remembered that these would not have been the habitual life postures, because tetrapods habitually extend the base of their neck and flex the anterior part, yielding the distinctive S-curve most easily seen in birds.

Introduction

The habitual posture of the necks of sauropod dinosaurs has been controversial ever since their body shape has been understood. Both elevated and more horizontal postures have been depicted, sometimes even in the same images—for example, Knight’s classic 1897 painting of Apatosaurus and Diplodocus (Fig. 1). See the introduction to Taylor & Wedel (2013) for a more comprehensive historical overview.

Figure 1: Charles R. Knight’s famous 1897 painting of sauropods, which were then considered amphibious

Figure 1: Charles R. Knight’s famous 1897 painting of sauropods, which were then considered amphibious.
In the foreground, Apatosaurus (“Brontosaurus” of his usage) wades in a lake, its neck erect. In the background, Diplodocus wanders on the shore, its neck held low and horizontal. These differences in posture may not represent different perceptions of the habitual behaviour of these different taxa, merely the postures these individuals happened to adopt at a particular moment.