Dinosaurs: New Findings & Theories

Jim

Justified & Ancient
Joined
Jan 19, 2016
Messages
1,129
Reaction score
1,244
Points
154
Location
NYS, USA
Dinosaurs were 'poisoned'


Scientists claim dinosaurs were poisoned to extinction and not killed off by an asteroid collision with Earth.

Researchers say the animals became extinct when arsenic and other toxic metallic elements were released into the atmosphere during volcanic eruptions.

The emissions, mainly in India and New Zealand, happened 500 to 800 years before an asteroid hit the Gulf of Mexico 65 million years ago.

The team at Vienna's Natural History Museum and the Russian Academy of Sciences came to this conclusion by examining earth samples taken from Styria in Austria.

http://www.ananova.com/news/story/sm_17 ... ?menu=news. scienceanddiscovery
The jury is out to how the animals died and it will always be speculation. Some claim the plant life was changing and the dinosaurs couldn't adapt. The theories are endless.
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
It could be the long-lost ancestor of the dinosaurs from Jurassic Park. A fossil discovered in the UK is thought to be the oldest Jurassic dinosaur ever found and is one of the most complete specimens from the time period.

The well-preserved remains of a juvenile dinosaur were found at Lavernock Point near Cardiff, Wales, a location that exposes rocks spanning from the late Triassic to the early Jurassic.

The fossil came from rocks that lie right in between these two eras, but subsequent analysis showed the specimen was from the early Jurassic.

“Only a few handfuls of specimens worldwide come from this time and most of them are only fragments,” saysSteven Vidovic from the University of Portsmouth in the UK, a member of the team that investigated the fossil.

https://www.newscientist.com/articl...paign=hoot&cmpid=SOC|NSNS|2016-GLOBAL-twitter
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
A pair of researchers has found that a dinosaur unearthed in Arizona back in 1942, had a record number of injuries and bone growth problems. In their paper published in the open access site, PLUS ONE, Phil Senter, with Fayetteville State University and Sara Juengst with Appalachian State University describe the condition of the dinosaur and suggest that it very likely had problems hunting and was almost certainly in a lot of pain for the latter period of its life.

In examining the dinosaur (Dilophosaurus wetherilli) the researchers found eight places where bones were either broken or were damaged through infections, they included: a fractured left shoulder blade, fractured left radius, an infection in its left ulna, two areas of damage due to bone infection in its left thumb, an injury to its right humorous and two examples of osteodysplasia, where the bone was deformed due to unusual growth.

The researchers theorize that several of the injuries likely occurred as the result of a single fight, from broken bones to infections due to piercings. There were also parts of bones that were simply missing—prior research has shown that unlike mammals, dinosaurs were unable to re-grow lost bone

http://phys.org/news/2016-02-dinosaur-bone-problems-lots-pain.html
 

Mythopoeika

I am a meat popsicle
Joined
Sep 18, 2001
Messages
42,805
Reaction score
33,499
Points
309
Location
Inside a starship, watching puny humans from afar
In examining the dinosaur (Dilophosaurus wetherilli) the researchers found eight places where bones were either broken or were damaged through infections, they included: a fractured left shoulder blade, fractured left radius, an infection in its left ulna, two areas of damage due to bone infection in its left thumb, an injury to its right humorous and two examples of osteodysplasia, where the bone was deformed due to unusual growth.
Humerus!
Heck, who writes this stuff...
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
Interstellar cloud could have wiped out the dinosaurs

A nebular winter could have doomed the dinosaurs. The clue is a thick layer of an extraterrestrial element on the ocean floor, now claimed to be the result of Earth colliding with a galactic cloud.

The most-heard explanation for the dinosaurs’ demise is an asteroid impact, which left a crater off the coast of Mexico and a worldwide 30-centimetre-thick layer of iridium, an element otherwise rare on Earth.

But every so often, astronomers suspect, the solar system ploughs into a giant nebula of molecular gas and dust much denser than typical interstellar space. The resulting galactic fog would have darkened skies and cooled the ground until a harsh winter set in. It would also have destroyed the ozone layer and halted photosynthesis.

Now Tokuhiro Nimura of the Japan Spaceguard Association in Ibara and colleagues claim such a collision could have ended the dinosaurs’ 150-million-year reign. At a site in the Pacific Ocean, the team found an iridium-rich sediment layer 5 metres thick, too thick for a sudden event like an asteroid strike to account for it. ...

https://www.newscientist.com/articl...have-wiped-out-the-dinosaurs/?utm_source=NSNS
 
  • Like
Reactions: Jim

rynner2

Gone But Not Forgotten
(ACCOUNT RETIRED)
Joined
Aug 7, 2001
Messages
55,247
Reaction score
9,094
Points
284
Suggestion for a good read:

The Black Cloud is a science fiction novel by astrophysicist Sir Fred Hoyle. Published in 1957, the book details the arrival of an enormous cloud of gas that enters the solar system and appears about to destroy most of the life on Earth by blocking the Sun's radiation. The cloud is later revealed as a sentient alien gaseous creature.

https://en.wikipedia.org/wiki/The_Black_Cloud

(I wonder if those Japanese researchers had read it! :p)
 

Mythopoeika

I am a meat popsicle
Joined
Sep 18, 2001
Messages
42,805
Reaction score
33,499
Points
309
Location
Inside a starship, watching puny humans from afar
I read that when I was a teenager.
Good book.
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
Researchers have used 'network theory' for the first time to visually depict the movement of dinosaurs around the world during the Mesozoic Era - including a curious exodus from Europe.

The research, published today in the Journal of Biogeography, also reaffirms previous studies that have found that dinosaurs continued to migrate to all parts of the world after the 'supercontinent' Pangaea split into land masses that are separated by oceans.

Study lead Dr Alex Dunhill from the School of Earth and Environment at the University of Leeds, said: "We presume that temporary land bridges formed due to changes in sea levels, temporarily reconnecting the continents."

"Such massive structures - spanning, for example, from Indo-Madagascar to Australia - may be hard to imagine. But over the timescales that we are talking about, which is in the order of tens of millions of years, it is perfectly feasible that plate tectonic activity gave rise to the right conditions for such land bridges to form."

In the study, the researchers used the Paleobiology Database that contains every documented and accessible dinosaur fossil from around the world. Fossil records for the same dinosaur families from different continents were then cross-mapped for different periods of time, revealing connections that show how they have migrated.

Some regions of the world, such as Europe, have extensive fossil records from a long history of palaeontology digs, while other parts of the world have been largely unexplored. To help account for this disparity in fossil records, which could otherwise skew the findings, the researchers applied a filter to the database records to only count the first time that a dinosaur family connection occurred between two continents.

The findings support the idea that, although continental splitting undoubtedly reduced intercontinental migration of dinosaurs, it did not completely inhibit it. ...

http://phys.org/news/2016-04-dinosaur-families-chose-exit-europe.html
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
An international team of scientists, including a graduate student lead author from Ohio University, have identified a new species of centrosaurine, a member of the large-bodied ceratopsians (horned dinosaurs) that diversified in North America and Asia during the final stages of the age of dinosaurs.

Although many fossils of this group have been discovered in North America, particularly from the northern portion of the Cretaceous landmass Laramidia (Alaska, Alberta, Montana, and Saskatchewan), relatively few have been recovered from the southern portion (Utah, Colorado, New Mexico, Texas, and Mexico) of this ancient continent.

The new species, named Machairoceratops cronusi (UMNH VP 20550), was discovered by scientists conducting paleontological and geological surveys in Grand Staircase-Escalante National Monument, southern Utah. With the help of professional excavators and volunteers from Ohio University and the Natural History Museum of Utah (NHMU), the team unearthed the characteristic horncores and other skull elements over the course of three field seasons.

Comparisons with other horned dinosaurs revealed unique features, indicating the animal was different from other horned dinosaurs—including those from elsewhere in Utah, according to a study the team published today in PLOS ONE. Lead author and Ohio University graduate student Eric Lund stated "The discovery of Machairoceratops not only increases the known diversity of ceratopsians from southern Laramidia, it also narrows an evolutionary information gap that spans nearly 4 million years between Diabloceratops eatoni from the lower middle Wahweap Formation and Nasutoceratops titusi from the overlying Kaiparowits Formation ".



Read more at: http://phys.org/news/2016-05-paleontologists-species-horned-dinosaur-southern.html#jCp
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
In the Mesozoic, the time of the dinosaurs, from 252 to 66 million years ago, marine reptiles such as ichthyosaurs and plesiosaurs were top predators in the oceans. But their origins and early rise to dominance have been somewhat mysterious.

New research published this week in the journal Paleobiology by palaeobiologists from the University of Bristol shows that they burst onto the scene, rather than expanding slowly into their ecosystems.

Lead author of the study Dr Tom Stubbs said: "We show that when marine reptiles first entered the oceans in the Triassic period, they rapidly became very diverse and had many morphological adaptations related to feeding on varied prey. Within a relatively short space of time, marine reptiles began feeding on hard-shelled invertebrates, fast-moving fish and other large marine reptiles. The range of feeding-related morphological adaptations seen in Triassic marine reptiles was never exceeded later in the Mesozoic."

The new research uses the rich fossil record of Mesozoic marine reptiles to statistically quantify variation in the shape and function of their jaws and teeth. Up to now, studies had been based mainly on estimates of their biodiversity, or number of species, through time. The new study explores the range of shapes and sizes, and ties characters of the shape of the jaws and teeth to modes of life, including their specialised modes of feeding. ...

http://phys.org/news/2016-05-rapid-mesozoic-sea-dragons.html

Articles on Marine Saurs have in the past resulted in lively debates on this thread. Hopefully this will result in more discussion.
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
Early armored dino from Texas lacked cousin's club-tail weapon, but had a nose for danger
May 24, 2016 in Other Sciences / Archaeology & Fossils

Pawpawsaurus lived 100 million years ago during the Cretaceous Period. It was first identified from a skull found in north Texas. Credit: Karen Carr
Pawpawsaurus's hearing wasn't keen, and it lacked the infamous tail club of Ankylosaurus. But first-ever CT scans of Pawpawsaurus's skull indicate the dino's saving grace from predators may have been an acute sense of smell.

Well-known armored dinosaur Ankylosaurus is famous for a hard knobby layer of bone across its back and a football-sized club on its tail for wielding against meat-eating enemies.

It's prehistoric cousin, Pawpawsaurus campbelli, was not so lucky. Pawpawsaurus was an earlier version of armored dinosaurs but not as well equipped to fight off meat-eaters, according to a new study, said vertebrate paleontologist Louis Jacobs, Southern Methodist University, Dallas. Jacobs is co-author of a new analysis of Pawpawsaurus based on the first CT scans ever taken of the dinosaur's skull.

A Texas native, Pawpawsaurus lived 100 million years ago during the Cretaceous Period, making its home along the shores of an inland sea that split North America from Texas northward to the Arctic Sea.

Like Ankylosaurus, Pawpawsaurus had armored plate across its back and on its eyelids. But unlike Ankylosaurus, Pawpawsaurus didn't have the signature club tail that was capable of knocking the knees out from under a large predator.

Ankylosaurus lived about 35 million years after Pawpawsaurus, around 66 million years ago toward the end of the Cretaceous. During the course of its evolution, ankylosaurids developed the club tail, and bone structure in its skull that improved its sense of smell and allowed it to hear a broader range of sounds. "Stable gaze" also emerged, which helped Ankylosaurus balance while wielding its clubbed tail.

"CT imaging has allowed us to delve into the intricacies of the brains of extinct animals, especially dinosaurs, to unlock secrets of their ways of life," said Jacobs, a professor in the SMU Roy M. Huffington Department of Earth Sciences. ...

http://phys.org/news/2016-05-early-armored-dino-texas-lacked.html
 

PeteByrdie

Privateer in the service of Princess Frideswide
Joined
Jan 19, 2014
Messages
2,290
Reaction score
2,084
Points
159
An interesting creature not related to the dinosaurs but often mistaken for one

One of my favourite prehistoric creatures when I wa small.
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
Dinosaurs May Have Cooed, Not Roared

Contrary to the big, scary roars that we see at the movies, dinosaurs, even the large ones, might not have roared at all.

Just as we now know that dinosaurs had feathers and potentially had mating rituals similar to modern birds, it's very possible that dinosaurs sounded more like birds than we'd like to think.

In a paper published in Evolution researchers raise the possibility that the sounds some birds make (coos, booms, and hoots) might have their roots in the vocalizations of their ancestors: dinosaurs.

“To make any kind of sense of what nonavian dinosaurs sounded like, we need to understand how living birds vocalize,” co-author of the paper Julia Clarke said. “This makes for a very different Jurassic world. Not only were dinosaurs feathered, but they may have had bulging necks and made booming, closed-mouth sounds.”

A closed-mouth sound is one that some birds make while keeping their beaks shut, instead producing noises in their throat. In a press release the authors note that the sound is much lower pitch than other open mouth vocalizations, like a songbird's tune. Instead, they say, it might have more in common with an ostrich.

“Looking at the distribution of closed-mouth vocalization in birds that are alive today could tell us how dinosaurs vocalized,” Chad Eliason, a co-author of the study said. “Our results show that closed-mouth vocalization has evolved at least 16 times in archosaurs, a group that includes birds, dinosaurs and crocodiles. Interestingly, only animals with a relatively large body size (about the size of a dove or larger) use closed-mouth vocalization behavior.” ...

http://www.msn.com/en-us/news/offbeat/dinosaurs-may-have-cooed-not-roared/ar-BBufY1z
 

Jim

Justified & Ancient
Joined
Jan 19, 2016
Messages
1,129
Reaction score
1,244
Points
154
Location
NYS, USA
On the other hand let's remember the load roaring bellows of an adult male alligator, so who knows? Some claim these the most intelligent and highly developed of modern day reptiles are related to dinosaurs. Crocodilians have a multi-chambered heart, ability to regulate body temp to a degree, care for their young and a strong memory.
 
Last edited:

oldrover

Justified & Ancient
Joined
Oct 18, 2009
Messages
4,002
Reaction score
1,458
Points
169
Crocodilians are related to dinosaurs, they're both in the archosaur group. But birds are dinosaurs.

As an aside, the animal noise I truly cannot stand to hear, it really, really turns me. Is that horrible hollow noise of a croc's jaw slamming shut. Oooh I hate just thinking about it.
 

PeteByrdie

Privateer in the service of Princess Frideswide
Joined
Jan 19, 2014
Messages
2,290
Reaction score
2,084
Points
159
Those arms aren't made for hugging: New species of predatory dinosaur found to have tiny two-foot-long forelimbs just like T-rex

While it may have had a ferocious set of teeth and a terrifying turn of speed, Tyrannosaurus rex is also famed for its absurdly weedy 'arms'.

Now experts have found the dinosaur's small forelimbs are perhaps not as unique as first thought.

Palaeontologists have discovered a new species of dinosaur in northern Patagonia that has similar short arms with two-fingered claws that look similar to those of the famous predator.


However, the newly discovered carnivorous dinosaur is not thought to be closely related to the T. rex, suggesting its stumpy forelimbs may have evolved independently.

...

http://www.dailymail.co.uk/sciencet...-dinosaur-tiny-forelimbs-just-like-T-rex.html
 

Jim

Justified & Ancient
Joined
Jan 19, 2016
Messages
1,129
Reaction score
1,244
Points
154
Location
NYS, USA
But birds are dinosaurs.
I think it's speculation to say that that birds are dinosaurs. Perhaps some dinosaurs had bird like traits , but dinosaurs = to birds, not so sure. They are separate vertebrates. Sure some had feather or feather-like covering. Still I can't quite see the bird like analogy of an Apatosaurus, a Stegosaurus or an Ankylosaurus for example for some un-bird like examples. As for them making bird like sounds this also is a highly speculative theory.
 

PeteByrdie

Privateer in the service of Princess Frideswide
Joined
Jan 19, 2014
Messages
2,290
Reaction score
2,084
Points
159
I think it's speculation to say that that birds are dinosaurs.
Nah, it's based on a massive amount of evidence. They don't just make this stuff up, you know. It's pretty hard to avoid the conclusion that birds are theropod dinosaurs, unless your definition of 'theropod' is 'a dinosaur of the theropod lineage that isn't a bird.'

Perhaps some dinosaurs had bird like traits , but dinosaurs = to birds, not so sure. They are separate vertebrates. Sure some had feather or feather-like covering. Still I can't quite see the bird like analogy of an Apatosaurus, a Stegosaurus or an Ankylosaurus for example for some un-bird like examples.
Can you see much similarity between those ornithischian dinosaurs you mentioned and velociraptor or t-rex? If not, does that mean they're not all dinosaurs? What does 'separate vertebrates' mean? How distantly related do taxa have to be to be described as separate, or how closely to be described as the same thing?
 
Last edited:

oldrover

Justified & Ancient
Joined
Oct 18, 2009
Messages
4,002
Reaction score
1,458
Points
169
I think it's speculation to say that that birds are dinosaurs. Perhaps some dinosaurs had bird like traits , but dinosaurs = to birds, not so sure. They are separate vertebrates. Sure some had feather or feather-like covering. Still I can't quite see the bird like analogy of an Apatosaurus, a Stegosaurus or an Ankylosaurus for example for some un-bird like examples. As for them making bird like sounds this also is a highly speculative theory.
Jim, as Pete has replied, this really isn't speculative.

There's a basic division in the dinosaur evolutionary tree, between 'lizard' and 'bird hipped'. Both were present in the Triassic, the period in which true dinosaurs first appeared. Both sides of this very early divergence are now known to have had feathers. Indicating that this was a feature of their common ancestor. And in both, the earliest known body plan is that of a biped.

The 'lizard hipped side went on the produce, the sauropods, theropods, and modern birds. Birds are 'lizard hipped dinosaurs'. The other, 'bird hipped dinosaurs' went on to produce among others the ankylosaurs and stegosaurs.

So in relation to your reservations, the most significant point to make again, is that all these diverse body plans were later developments from a common basal form. And as a feathered biped, one which perhaps doesn't seem too unlikely to peg as a bird ancestor.

Look at it this way, there's every bit of a seemingly huge gulf between a bat and a whale, than between a robin and a sauropod. Or an echinda and a buffalo, as there is between a duck and a ceratopsian. But we know for certain they're all part of the same clade.
 
Last edited:

rynner2

Gone But Not Forgotten
(ACCOUNT RETIRED)
Joined
Aug 7, 2001
Messages
55,247
Reaction score
9,094
Points
284
X-rays reveal complete dino skeleton
By Paul Rincon Science editor, BBC News website
27 July 2016

Scientists have used high-power X-rays to "see inside" an exquisite and complete dinosaur specimen.
The skeleton belongs to a small, plant-eating dinosaur which lived 200 million years ago - at the beginning of the Jurassic Period.

Although this species was widespread at the time, scientists have largely had to rely on incomplete fossils.
The analysis was carried out at the ESRF facility in Grenoble, France, and showed that the specimen was juvenile.
The skeleton is too small and fragile, and the rocks around it too hard, to allow it to be studied by conventional means.
In addition, the rock matrix in which the fossil is preserved contains trapped minerals which prevented it from being scanned in a standard CT scanner.
The specimen was discovered in a stream bed on a farm in the Eastern Cape province of South Africa by palaeontologist Billy de Klerk.

"There's still a lot we don't know about early plant-eating dinosaurs," said Prof Jonah Choiniere from the University of the Witwatersrand in Johannesburg, South Africa.
"We need new specimens like this one and new technology like the synchrotron to fill in those gaps."

Prof Choiniere, along with Dr Vincent Fernandez, from the ESRF (European Synchrotron), scanned the specimen with high-powered X-rays to understand how the species, Heterodontosaurus tucki, ate, moved, and breathed.

Scanning the fist-sized skull might allow the scientists to perform a 3D reconstruction of the animal's brain, offering insights into its lifestyle - including its sense of smell, and whether it was capable of complex behaviours.
The scientists think the diminutive dinosaur used its back teeth to grind down plant food. In other animals with similar anatomy, this requires the teeth to be replaced due to wear and tear.
The team members said they can now begin testing this theory and others regarding the dinosaur's biology and behaviour.

http://www.bbc.co.uk/news/science-environment-36901907

Plenty of photos on page. This specimen seems to be feathered: for those interested in the Dinosaurs/Birds debate, I watched this on iPlayer yesterday:

Fossil Wonderlands: Nature's Hidden Treasures - 2. Feathered Dinosaurs

Professor Richard Fortey travels to north eastern China to see a fossil site known as the 'Dinosaur Pompeii' - a place that has yielded spectacular remains of feathered dinosaurs and rewritten the story of the origins of birds. Among the amazing finds he investigates are the feathered cousin of T-rex, a feathered dinosaur with strong parallels to living pandas, and some of the most remarkable flying animals that have ever lived.

http://www.bbc.co.uk/iplayer/episod...atures-hidden-treasures-2-feathered-dinosaurs
 

ramonmercado

CyberPunk
Joined
Aug 19, 2003
Messages
51,391
Reaction score
25,967
Points
309
Location
Eblana
A dinosaur has been diagnosed with severe arthritis 70 million years after its death.

Scientists believe the hadrosaur, a plant-eating duck-billed dinosaur, must have endured considerable suffering before reaching the end of its life.

X-ray analysis of its fossilised elbow joint revealed evidence of septic arthritis, an especially nasty form of the disease caused by infection and known to afflict modern birds, crocodiles and humans.

A micro-tomography scan — a high resolution version of the kind of CT scans used in hospitals — showed that the joint was fused and covered in bony growths.

It is the first time septic arthritis has been seen in a dinosaur, although another arthritic condition called osteomyelitis was quite common among the creatures.

In this case, osteomyelitis was ruled out because of the “highly reactive” bone growth and the location of the affected area around the elbow joint. ...

https://www.newscientist.com/articl...of-dinosaur-arthritis-shows-it-lived-in-pain/
 
Top