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A Big Dinosaur

Started by Recusant, January 29, 2021, 05:05:53 AM

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Recusant

I've been neglecting my science story hound endeavours. Distracted by this, that, and the other thing. Hounds be like that sometimes.

The thumping as this one went by would have been significant.

"Gigantic dinosaur unearthed in Argentina could be largest land animal ever" | Phys.org

QuoteA team of researchers with Naturales y Museo, Universidad de Zaragoza and Universidad Nacional del Comahue has found evidence that suggests the remains of a dinosaur discovered in Argentina in 2012 may represent a creature that was the largest ever to walk the Earth. In their paper published in the journal Cretaceous Research, the group describes the fossilized remains that have been found so far and what they have revealed.

The largest creature ever to live is believed to be the blue whale—the largest of which grow to 33.6 meters long. The biggest land creatures are believed to have been the dinosaurs—of them, the titanosaur (as their name suggests) is believed to be the largest. And of those, Argentinosaurus represents the largest that left enough evidence for it to be classified the heaviest—at approximately 36.5 meters in length and weighing in at a hundred tons, it would have dwarfed today's land animals by a considerable amount. Researchers studying Patagotitan fossils (another titanosaur found in Patagonia) have suggested some of them might have broken the record for the largest, but there was insufficient fossil evidence to prove it. In either case, the researchers studying the new remains have begun to believe that they have found an even bigger titanosaur.

[Continues . . .]
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Icarus

The unthinkably large creatures are thought to have been herbivores.  The nourishment required for a 100 ton creature would surely have wiped out entire forests.  Their presence must have made life difficult for small animals who depended on vegetation for survival.

Icarus

I am skeptical that the beast could have weighed even close to 100 tons. Here's why...................
It is a biped. It can perambulate
It must have had very large feet

Following is an exercise of little consequence except that I like to play with numbers.........................

There is the matter of soil bearing; the surface that the beast walked on.  The limit of stable footing varies from solid rock to sandy soil.  Limits are:
Solid bed rock.... 12000 pounds per square foot
loose rock...........6,000 psf
gravel and sand...5,000 psf
Sandy soil...........3,000 psf

If the beast had feet that covered 10 square feet then his foot and leg pressure would amount to    20,000 psf.
                                                  20 square feet of foot surface would have had a unit pressure    10,000 psf
                                                  30 square feet of foot surface ..........................unit pressure     6,6oo  psf
These approximate figures imply that the Tyranasaurus had to have feet with a footprint area of 65 square feet if he were to survive a walk on sandy soil. That is about 6.0 square meters of foot surface. That also uses the improbable notion that his feet had evenly distributed support area. 

For perspective, a typical American bedroom is  about 11 meters square (10 x 12 feet) . Larger in mega dollar houses.

feel free to check my arithmetic.  I sometimes get it wrong. (geriatric reality)



xSilverPhinx

100 tonnes? I think 'big' would be an understatement! :lol:
I am what survives if it's slain - Zack Hemsey


Recusant

I think your mathematics is fine, Icarus and your point is well taken. However, titanosaurs were quadrupeds, so while they did have large feet, not so large as they would have been if they were trying to waddle all that weight around on two feet (and perhaps a tail).
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Icarus

Recent discoveries in the south of Wales have some imprints of small dinosaurs, estimated height of 75 cm. It seems that there are many archeological finds for dinosaur types in that particular area.  The evidence most recently found has a foot imprint that resembles the bird like foot mechanism, claws and all.

The big one from Argentina or Patagonia as shown, indeed is a quadraped. Whether it used the fore legs for propulsion is unclear.  Perhaps so because it would have needed the extra suspension to support the enormous weight.  In any case that thing was one big creature.  I suspect that it might have been slow and clumsy simply because of it huge mass.

Recusant

#6
Quote from: Icarus on January 31, 2021, 01:38:17 AM
Recent discoveries in the south of Wales have some imprints of small dinosaurs, estimated height of 75 cm. It seems that there are many archeological finds for dinosaur types in that particular area.  The evidence most recently found has a foot imprint that resembles the bird like foot mechanism.

Yes, Lark sent a link with the story--the print was found by a very young girl on a walk with her father.

"Dinosaur footprint found by girl, four, on Barry beach" | BBC

Quote

Image Credit: National Museum Wales




A well-preserved dinosaur footprint has been discovered by a four-year-old girl on a beach.

Lily Wilder spotted it at Bendricks Bay, Barry, in the Vale of Glamorgan - and scientists believe it could help establish how they walked.

The footprint, spotted in January, is 220 million years old and had been preserved in mud.

While it is impossible to tell what type left it, the print is 10cm long and likely from a 75cm tall dinosaur.

National Museum Wales palaeontology curator Cindy Howells described it as "the best specimen ever found on this beach".

[Continues . . .]
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


xSilverPhinx

I am what survives if it's slain - Zack Hemsey


Recusant

More from Argentina: An early titanosaur that's been given an extra-cool name: Ninjatitan zapatai. It wasn't a big ninja, but is named after Sebastian Apesteguia, an Argentinian paleontologist nicknamed "The Ninja," and technician Rogelio Zapata, who both have worked for several years in the region where the fossil was discovered. Apesteguia was the first paleontologist to look for fossils there.

Not the same find as the one described in the original post.  :heyhey:

"Paleontologists Discover Oldest Known Titanosaur" | Sci-News

Quote

Ninjatitan zapatai.
Image credit: Jorge González.




Ninjatitan zapatai belongs to Titanosauria, a diverse group of sauropod (long-necked plant-eating) dinosaurs.

This group includes species ranging from the largest known terrestrial vertebrates to 'dwarfs' no bigger than elephants.

"During evolutionary history, sauropods had different moments, different pulses of gigantism, which were not only related to the group of titanosaurs," said Dr. Pablo Ariel Gallina, a paleontologist at the Fundación Azara in Maimonides University and CONICET [link goes to an interesting article in Spanish].

"There were large animals towards the end of the Jurassic period, such as Apatosaurus and Brachiosaurus. And, already in the line of titanosaurs, the pulse with the largest giants occurs towards the middle of the Cretaceous period, with species such as Patagotitan, Argentinosaurus or Notocolossus."

Ninjatitan zapatai was about 20 m (66 feet) in length, and had a long neck and tail.

"The main importance of Ninjatitan zapatai, beyond the fact that it is a new species of titanosaur, is that it is the earliest record worldwide for this group," Dr. Gallina said.

[Continues . . .]

The paper is behind a paywall.

QuoteAbstract [paragraph breaks added]

The titanosaur sauropod record of Patagonia, mainly recovered from Upper Cretaceous strata, is probably the richest worldwide. Here we present a new sauropod dinosaur, Ninjatitan zapatai gen. et sp. nov., from the Lower Cretaceous Bajada Colorada Formation (Berriasian–Valanginian) of north Patagonia (Neuquén Province, Argentina), from which postcranial remains are preserved.

The anatomical analysis and comparisons performed in this specimen evidence strong affinity with titanosaur sauropods. This assumption is corroborated with the inclusion of the new taxon in an updated phylogenetic data matrix. The cladistic analyses indicate that Ninjatitan could be considered the earliest known titanosaur sauropod. The combination of features such as the presence of procoelous anterior caudal centra, the pneumatized neural arch of anterior caudal vertebrae, and the posterodorsal border of the scapular acromion near the glenoid level supports its titanosaur affinities.

The presence of a basal titanosaurian sauropod in the lowermost Cretaceous of Patagonia supports the hypothesis that the group was established in the Southern Hemisphere and reinforces the idea of a Gondwanan origin for Titanosauria. The Bajada Colorada sauropod fauna represents one of the most diverse and unique associations from the lowermost Cretaceous worldwide recorded.

"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Recusant

#9
Using fossil trackways (ancient footprints) to identify the gait of the really big sauropods:

"We discovered how the largest dinosaurs walked – and it was more like hippos than elephants" | The Conversation

QuoteWhile our knowledge of dinosaurs and other extinct animals has dramatically increased during the last couple of decades, their gaits – the order and timing of how animals move their legs – have remained a blind spot.

We are particularly interested in the giant long-necked sauropod dinosaurs, which include the largest animals that walked the earth, including such famous species as Diplodocus, Brontosaurus and Brachiosaurus. How did these giants move? What role did efficiency and stability play during their locomotion?

Those questions have not been easy to answer. The problem is that skeletons are the remains of deceased animals and don't preserve motion. So reconstructing gaits based on fossilised bones can only indirectly provide clues, and are far from conclusive.

As it happens, there is another type of fossil that records the activity of an animal when it was alive, and they are known as fossil trackways. But until now, extracting gait information about extinct dinosaurs from these footprints has proved difficult.

A 2016 study demonstrated that two animals of different sizes and using different gaits could produce identical track patterns. This means that to identify gait from the tracks we would need to know the trunk length of the animal (distance from hip to shoulder). Unfortunately it could not be accurately estimated from tracks so we were left with too many unknowns.

But one important aspect had not yet been taken into account – the variation along a set of tracks caused by small changes in speed. In our new study, we used this variation to present a new method to use tracks to work out which gait had been used.

[. . .]


[Continues . . .]

The paper is open access:

"A new method to calculate limb phase from trackways reveals gaits of sauropod dinosaurs" | Current Biology

"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Recusant

Oh hey, another item for the sauropod/titanosaur thread.  :yes!:

"First near-complete sauropod dinosaur skull found in Australia hints at ancient links between continents" | The Conversation

QuoteIn May and June of 2018, Australia's first near-complete skull of a sauropod – a group of long-tailed, long-necked, small-headed dinosaurs – was found on a sheep station northwest of Winton in Queensland.

I was part of the dig team from the Australian Age of Dinosaurs Museum that made the discovery, and subsequently had the privilege of leading the team that studied the skull. After years of work, our results are published today in Royal Society Open Science.

The skull belonged to a creature we have dubbed "Ann": a member of the species Diamantinasaurus matildae which shows surprising similarities to fossils found halfway across the world, lending weight to the theory that dinosaurs once roamed between Australia and South America via an Antarctic land connection.

[Continues . . .]

The paper is open access:

"A nearly complete skull of the sauropod dinosaur Diamantinasaurus matildae from the Upper Cretaceous Winton Formation of Australia and implications for the early evolution of titanosaurs" | Royal Society Open Science

QuoteAbstract:

Titanosaurian sauropod dinosaurs were diverse and abundant throughout the Cretaceous, with a global distribution. However, few titanosaurian taxa are represented by multiple skeletons, let alone skulls. Diamantinasaurus matildae, from the lower Upper Cretaceous Winton Formation of Queensland, Australia, was heretofore represented by three specimens, including one that preserves a braincase and several other cranial elements.

Herein, we describe a fourth specimen of Diamantinasaurus matildae that preserves a more complete skull—including numerous cranial elements not previously known for this taxon—as well as a partial postcranial skeleton. The skull of Diamantinasaurus matildae shows many similarities to that of the coeval Sarmientosaurus musacchioi from Argentina (e.g. quadratojugal with posterior tongue-like process; braincase with more than one ossified exit for cranial nerve V; compressed-cone–chisel-like teeth), providing further support for the inclusion of both taxa within the clade Diamantinasauria.

The replacement teeth within the premaxilla of the new specimen are morphologically congruent with teeth previously attributed to Diamantinasaurus matildae, and Diamantinasauria more broadly, corroborating those referrals. Plesiomorphic characters of the new specimen include a sacrum comprising five vertebrae (also newly demonstrated in the holotype of Diamantinasaurus matildae), rather than the six or more that typify other titanosaurs. However, we demonstrate that there have been a number of independent acquisitions of a six-vertebrae sacrum among Somphospondyli and/or that there have been numerous reversals to a five-vertebrae sacrum, suggesting that sacral count is relatively plastic.

Other newly identified plesiomorphic features include: the overall skull shape, which is more similar to brachiosaurids than 'derived' titanosaurs; anterior caudal centra that are amphicoelous, rather than procoelous; and a pedal phalangeal formula estimated as 2-2-3-2-0. These features are consistent with either an early-branching position within Titanosauria, or a position just outside the titanosaurian radiation, for Diamantinasauria, as indicated by alternative character weighting approaches applied in our phylogenetic analyses, and help to shed light on the early assembly of titanosaurian anatomy that has until now been obscured by a poor fossil record.
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Tank

If religions were TV channels atheism is turning the TV off.
"Religion is a culture of faith; science is a culture of doubt." ― Richard P. Feynman
'It is said that your life flashes before your eyes just before you die. That is true, it's called Life.' - Terry Pratchett
Remember, your inability to grasp science is not a valid argument against it.