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What are the chances that Tyrannosaurus Rex could roar?


Tyrannosaurus Rex is now thought to have possibly had lips. Less of chance of it roar though I was told by a friend just because there are birds doesn't mean they can't.

Evolution isn't linear, just because one branch of a tree could/couldn't do something, doesn't mean 70+ million years later descendants could/couldn't do it too?


Careful now: T Rex was not a bird, it was a non-avian theropod. Birds are dinosaurs but not all dinosaurs are birds. In the same way, tigers are cats but not all cats are tigers.

The argument that T Rex could not roar is not only based on none of its closest relatives being able to as you seem to indicate. Dinosaurs (and by extension birds) are archosaurs, a clade that includes crocodilians too and crocodilians are quite a bit more close to the basal form of archosaurs than T Rex was. Crocodilians can only sort of "hiss", not roar in the colloquial sense. And birds cannot roar. This is a decent start to a thought process but this isn't really the argument for why dinosaurs likely didn't roar in the past.

Researchers who have studied the potential vocalizations of prehistoric, non-avian dinosaurs have found indications that similar closed-mouth vocalization to those found in other living archosaurs are very probable: https://news.utexas.edu/2016/07/11/dinosaurs-may-have-cooed-like-doves

Closed-mouth vocalization is not really compatible with what people typically think of as roaring. It still allows a variety of sounds that don't necessarily (though perhaps probably) somewhat resembled crocodialian or simple bird vocalizations. So no, it's not impossible that some non-avian dinosaurs could roar but the current state of our knowledge is that they very likely could not.


Sergey Krasovskiy / Stocktrek Images / Getty Images

Giganotosaurus (pronounced GEE-gah-NO-toe-SORE-us) is Greek for "giant southern lizard," not "gigantic lizard," as it's often mistranslated (and mispronounced by people unfamiliar with classical roots, as "giganotosaurus"). This common error can be attributed to the numerous prehistoric animals that do, in fact, partake of the "giganto" root—two of the most notable examples being the giant feathered dinosaur Gigantoraptor and the giant prehistoric snake Gigantophis.


What Sound Did T. rex Actually Make?

It's an iconic scene in every dinosaur movie: the huge, conquering carnivorous theropod rears back and lets out a terrifying bellow. But how close to reality are these sounds? Do we have any ways of using science to figure out what dinosaurs and other stem-birds may have sounded like? Do we have evidence that they made sounds at all?

Sound effects artists spend huge amounts of time sampling vocalizations from various animals to create just the right mix to create an unfamiliar, otherworldly roar. Take a look at this Vulture article . It lists some of the amazing places sound effects artists went to create the sounds for the dinosaur movie Jurassic Park in 1993. The iconic T. rex roar was created by playing with the speed and frequency of elephant and dog sounds. The raptor sounds were created using tortoises, horses, and geese. Only one of these sources – the goose – is an animal anywhere close to being related to dinosaurs. Many of the other sounds are re-mixed from various mammals, the kinds of sounds we expect large predators (which today are almost all mammalian) to have, thus increasing the scare factor for audiences.

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In reality, mammalian or even tortoise sounds are probably not the best analogue for real-life dinosaur sounds. But then what are? The only real evidence for stem-bird vocalizations in fossils comes from two sources: good old phylogenetic bracketing, and correlations between bone structure and soft tissue vocal chords. ( Phil Senter reviewed this evidence in his 2009 paper on evidence for vocalization in prehistoric animals .)

Many groups of animals today can make noise using vocal chords of some kind, and most of these do so using some kind of larynx or larynx-like vocal organ. Most groups of mammals vocalize, so the prince of a larynx is probably ancestral for our own major group, though how far back down the stem-mammal lineage the larynx might go is hard to say. One line of evidence cited by Senter is the presence of a tympanic ears, which would be necessary to hear any complex vocal communication being made. The earliest stem-mammals lacked ears, which don't appear until almost the mammalian crown group, though the grade leading up to the crown may have been able to hear some low-frequency airborne sounds.

The almost random distribution of tympanic ears and the larynx in modern tetrapods indicates that these features evolved multiple times, for example in frogs, some salamanders, mammals, turtles, gekkotan lizards, and crocodiles. This is supported by the fact that birds lack the larynx entirely, and vocalize with an entirely different organ called the syrinx. While it is possible that the ancestors of birds had a larynx and it was later replaced with the syrinx, there is currently no evidence to support or test this possibility, and it should be assumed that stem-birds never had a larynx.

Above: Pigeon anatomy, via Wikimedia Commons . The Syrinx is labeled number 5.

Can we tell how far down the bird family tree the syrinx evolved? It turns out that the presence of a sound-making syrinx is strongly tied with the presence of a clavicular air sac, without which the syrinx could not function (Olsen & Joseph, 2011). Like other air sacs, the clavicular sac creates hollow spaces in the bones of the forelimb and shoulder girdle. There are three known stem-bird clades that have such air sacs: Pterosauria, Aerosteon, andOrnithothoraces.

The latter, of course, is the one that includes birds, so the air sacs in non-avian ornithothoracines are probably homologous with those of modern birds. Aerosteonand pterosaurs, though, are problematic. Aerosteon are bracketed on both sides by theropods known to definitely lack clavicular air sacs, so the presence in the former taxon is probably an independent evolution possibly unrelated to vocalization. The same goes for pterosaurs, which may have independently evolved air sacs to help cope with flight, and independently developed the air sacs in their forelimbs, possibly without any relation to a syrinx (Senter, 2009).

Does this mean T. rex and her dinosaurian buddies were all silent? The answer is no, because animals can make plenty of sounds by means other than a larynx or syrinx, just not the mammal- or bird-like sounds we are used to associating with them in pop culture. Hisses, drumming sounds, clicking or rattling sounds can all be produced just by moving air and not vocalizing. Non-ornithothoracine stem-birds could also have made physical sounds, like whip-cracking tails in diplodocids, beak-clacking, jaw-grinding, water-slapping, etc. Some birds can also make low booming and drumming calls using only passages through the trachea and cervical air sac, like emu and cassowary (Olsen & Joseph, 2011).

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What about the famous hooting horns and crests of lambeosaurines? Senter noted that even in modern animals, the presence of resonating chambers don't always correlate with the presence of vocal chords. Some snakes, for example, have massive resonating chambers in their skulls which amplify and modify the sound of their hiss. It's entirely plausible, Senter argued, and more in line with the other evidence, to think that Parasaurolophus used their crests to project loud hissing or drumming sounds, rather than trumpeting (Senter, 2009). However, it's also possible that the complex internal, trumpet-like tubes of such crests evolved because these animals lacked vocal chords. After all, a trumpet player doesn't vocalize into his instrument, he simply blows air through, and the internal "anatomy" of the trumpet create the musical sound. I have to disagree with Senter here and suggest that lambeosaurines did hoot and trumpet, but were probably one-note instruments, unless some kind of weird soft tissue allowed them to hit different "keys" and modify the sound. Either way, no syrinx or larynx should be required for this to work.

It needs to be noted that the larynx evolved many times in tetrapods, and it's entirely possible that some stem-bird lineages also independently evolved such an organ. But absent any kind of testable, direct evidence, or unusual sound-related structures like the ones found in lambeosaurines, any good scientist needs to presume that most of them could not vocalize the way depicted in movies.

So how did these animals communicate if their were largely silent and limited in vocal repertoire? Stem-birds, more than possibly any other group of tetrapods, are well-known for outlandishly flamboyant visual display structures. Huge, flashy crests, plates, spikes, sails, and frills abound in nearly every stem-bird group. The idea that these animals were very limited in audible communication may help explain why they developed such a dazzling array of visual communication devices. It is only in the ornithothoracines that we see direct evidence for acoustic communication and, maybe not coincidentally, this is the first group of stem-birds to become fully arboreal. For very small species living mostly hidden from each other in the dense leaves of trees, visual communication would become more difficult, and there would be selective pressure for alternate means of communication, such as sound, to evolve.

Bird calls may have developed initially to keep in touch between animals that had become hidden from each there in the trees and could no longer regularly maintain visual signals. Like songbirds today, which use visual but mainly vocal communication to find and attract mates, basal ornithothoracine protobirds may have become the first stem-birds to call to each other through the foliage.

So, what did T. rex say? It may have hissed and boomed like crocodiles, snakes, and emus. It may have been the strong, mostly-silent type. But it probably couldn't roar. Except, of course, in the next Jurassic Park film. Movie producers will never let science get in the way of a good scare!

  • Olsen, P., & Joseph, L. (2011). Stray Feathers: Reflections on the Structure, Behaviour and Evolution of Birds. Csiro Publishing.
  • Senter, P. (2008). Voices of the past: a review of Paleozoic and Mesozoic animal sounds: review . Historical Biology, 20(4): 255-287.

This post by Matthew P. Martyniuk originally appeared at his paleontological blog, DinoGoss . It has been republished with permission. Martyniuk is an illustrator and science educator specializing in Mesozoic birds and avian evolution. He has been drawing prehistoric flora and fauna since he first held a pencil, and became fascinated with the dinosaur/bird transition after discovering a copy of Gregory S. Paul's Predatory Dinosaurs of the World at his local library. His illustrations and diagrams have appeared in a variety of books, news articles, and television programs from Discovery, the Smithsonian, and the BBC. Follow him on Twitter .


The Tyrannosaurus Rex’s Dangerous and Deadly Bite

Tyrannosaurus rex has always been recognized as fearsome—the New York Times labeled it the “prize fighter of antiquity” when the first mounted T. rex bones were displayed in 1906—but thanks to two British researchers, it’s now clear that the giant carnivore bit harder than experts had thought. A lot harder.

From This Story

The Tyrannosaurus Rex known as Stan, excavated in South Dakota in 1992, is one of the most complete tyrannosaurus rex skeletons in the world. (Greg Latza / AP Images)

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Karl Bates, a biomechanics expert at the University of Liverpool, and Peter Falkingham, a paleontologist at the Royal Veterinary College, London, and Brown University, acknowledge that measuring the biomechanics of an extinct species “is notoriously difficult and involves numerous assumptions.” But for their assessment of T. rex’s bite, published in Biology Letters, they constructed a three-dimensional digital model of the animal’s skull and reconstructed the relevant jaw musculature, based on anatomical research on birds (which are, after all, living dinosaurs) and crocodilians (the closest living cousins to Dinosauria as a group). Previous assessments relied on extrapolations from crocodile bites or fossil T. rex tooth marks.

When Bates and Falkingham used computer models to simulate T. rex’s bite, the result was “quite surprising,” Bates told us: a maximum bite force of almost 12,800 pounds, about the equiva­lent of an adult T. rex’s body weight (or 13 Steinway Model D concert grand pianos) slamming down on its prey. That would make T. rex the hardest-biting terrestrial animal ever known. (C. megalodon, an extinct giant shark, bit at an estimated 41,000 pounds Deinosuchus, an ancient crocodilian, at about 23,000 pounds.) Bates and Falkingham’s figure was two to three times greater than previous estimates, six to seven times greater than the biting force they calculated for the dinosaur Allosaurus and about three and a half times greater than the hardest bite measured in an extant species, an Australian saltwater crocodile.

“The posterior part of the skull that housed the muscles was particularly large,” Bates says. Rare juvenile T. rex skeletons indicate that these dinosaurs were leggy runners with relatively shallow skulls incapable of anchoring muscles that would generate a bite proportional to the adults’. In Bates and Falkingham’s tests, juvenile T. rex bites topped out at about 880 pounds. But as the animal matured, its jaw-closing muscles grew exponentially, to the point where they were huge “even for an animal of its colossal size.”

Young T. rex were still formidable—they just targeted different prey. While the juveniles raced down small game, Bates notes, the adults had the power to bring down megaherbivores such as Edmontosaurus and Triceratops. This phenomenon, called resource partitioning, would have reduced competition between parents and offspring—a big evolutionary advantage. As if T. rex needed it.

About Riley Black

Riley Black is a freelance science writer specializing in evolution, paleontology and natural history who blogs regularly for Scientific American.


Dr. Universe: Did dinosaurs actually roar? – Susan, Spokane, Wash.

In the movies, we often hear dinosaurs let out big, scary sounds. If you’ve ever played with toy dinosaurs, maybe you’ve also made your little Tyrannosaurus rex roar.

While dinosaurs have a reputation for roaring, I wasn’t entirely certain whether or not they actually did so in real life. I asked my friend and Washington State University professor, Cynthia Faux.

“It’s impossible to say for sure,” Faux says. “But we can speculate.”

Faux is really curious about dinosaurs, especially those descendants of two-legged dinosaurs that soar through the sky today: birds.

Examining an animal’s voice box might give us clues about what kind of sound it made. There are lots of birds on our planet and they all have different tweets, caws, and chirps. Of course, a dinosaur’s voice box would have been much bigger than a bird’s voice box.

Sometimes when we want to learn about life in the past, we examine fossils. Fossils are preserved traces of plants and animals. Some scientists even study poop fossils to find out what animals ate. But not all parts of an animal can be traced through fossils. Some voice boxes are made up of soft tissue.

This soft tissue breaks down over time, which makes it hard to figure out exactly what kind of voice box a dinosaur used to make their sounds.

Scientists who conducted some of the most recent research into dinosaur sounds have found that the creatures actually might have cooed or boomed. In fact, that sound may been similar to the kinds of noises today’s emus or ostriches make, says Faux.

Roaring is also more of a mammal thing, Faux adds. Lions, tigers, and bears are all predators that roar— but they aren’t roaring all the time. When they do roar, it’s often to show their dominance or to scare away another animal.

After all, making a lot of sound when you approach your prey isn’t the brightest idea. It works much better to quietly sneak up on your prey, so they don’t know what’s coming.

There may have been some other ways dinosaurs communicated, too. Some dinosaurs may have displayed their feathers. Yes, some dinosaurs had feathers. They may have used them as a way to send messages to those around them—perhaps as a defense or to attract a mate.

Sauropods, plant-eating, four-legged dinosaurs that usually had long necks, were as big as houses and made a lot of noise just by walking around. Perhaps their stomping sent a message to those around them. Some dinosaurs may have communicated in a way similar to alligators. By creating vibrations in the water, they could let creatures around them know they are frightened and might strike.


Laboratory Part 2: Estimation of the Rates of Locomotion in Cretaceous Dinosaurs

In Part 2, you will calculate and compare the speed of T. rex and four of its large potential prey species (listed in Table 2). While we can determine the speed of cheetahs and gazelles very accurately because they are alive, one of the only ways to determine extinct dinosaurs’ speeds is to use fossilized trackways. Measurements of a dinosaur’s footprint length and stride length can be used to calculate speed (Table 2). In the data in Table 2, a footprint length is measured from the longest toe to the heel and sometimes a footprint width is used, measured from side to side at its largest point. The measurements are taken on the larger hind foot in four-legged dinosaurs. Stride length is measured from the heel impression of the left foot to the heel impression when that same left foot is put down again a stride later. Hip height (h) cannot be measured directly from the footprint trackway but can be estimated. Using data from living animals, Alexander (1976) developed a formula for calculating the speed of dinosaurs from trackways of their footprints:

Speed (m/s) = 0.25(acceleration due to gravity) 0.5 × (stride length) 1.67 × (hip height) –1.17 [Equation 1]

where hip height according to Alexander (h A ) is estimated to be 4× footprint length, and acceleration due to gravity (g) is 9.81 m/s.

A little later, Thulborn (1982, 1990) suggested the need to modify the speed estimates for different dinosaur groups, using different leg lengths or heights (h T ) in the calculations. These different hip heights by groups, called hip height conversion factors, were derived from direct measurements taken from dinosaur fossilized skeletons. Thulborn also developed the idea that L/h A , or relative stride length, could be used to determine whether the animal was walking (L/h A ≤ 2.0), trotting (2.0 < L/h A < 2.9), or running (L/h A ≥ 2.9).

Table 2 has representative foot-length and stride-length numbers for T. rex and four potential prey species, plus columns of numbers calculated using Equation 1 (Alexander, 1976), along with the hip height conversion factors and relative stride length calculations of Thulborn (1982, 1990). Calculate and insert the numbers in columns E and G. You can obtain calculated speeds for both the Alexander and Thulborn methods by inserting the numbers into the online Dinosaur Speed Calculator (Sorby Geology Group, University of Sheffield, 2010). You will input the foot length (Table 2, column C), Thurlborn hip height conversion factor (Table 2, column F), and stride length (Table 2, column D). The Calculator will supply the answers to Table 2, columns H, I, and J. Note that if you use direct measurements and calculate using the formula, the speed (m/s) can be converted into kilometers per hour by multiplying (m/s) by 3.6 = kilometers per hour, and (kilometers per hour)/0.621 = miles per hour. Compare your results with those published by researchers in this field (Table 3). Can you conclude that these estimates of dinosaurs’ running speeds are very accurate?

Published calculated speeds of Cretaceous dinosaurs.

Genus . Speed . Maximum Speed .
Tyrannosasurus 15–20 km/h (Thulborn, 1982)
32 km/h (Farlow et al., 1995)
18–40 km/h (Hutchinson & Garcia, 2002)
28.8 km/h (Sellers & Manning, 2007)
24 km/h (Zimmermann, 2012) 24–40 km/h (Paul, 2010, p. 31)
Triceratops 25 km/h (Thulborn, 1982)
Ankylosaurus6–8 km/h (Thulborn, 1982) 6–8 km/h (Thulborn, 1982)
Edmontosaurus12–17 km/h (Thulborn, 1982) 20–30 km/h (Thulborn, 1982) 61.2 km/h (Sellers et al., 2009)
Alamosaurus3.6–4.0 km/h (Alexander, 1976) 4.7–4.9 km/h (González Riga, 2011) 12–17 km/h (Thulborn, 1982) 25 km/h (Paul, 2010, p. 31)
Genus . Speed . Maximum Speed .
Tyrannosasurus 15–20 km/h (Thulborn, 1982)
32 km/h (Farlow et al., 1995)
18–40 km/h (Hutchinson & Garcia, 2002)
28.8 km/h (Sellers & Manning, 2007)
24 km/h (Zimmermann, 2012) 24–40 km/h (Paul, 2010, p. 31)
Triceratops 25 km/h (Thulborn, 1982)
Ankylosaurus6–8 km/h (Thulborn, 1982) 6–8 km/h (Thulborn, 1982)
Edmontosaurus12–17 km/h (Thulborn, 1982) 20–30 km/h (Thulborn, 1982) 61.2 km/h (Sellers et al., 2009)
Alamosaurus3.6–4.0 km/h (Alexander, 1976) 4.7–4.9 km/h (González Riga, 2011) 12–17 km/h (Thulborn, 1982) 25 km/h (Paul, 2010, p. 31)

Why it matters

Once we figured out the average population size, we were able to calculate the fossilization rate for T. rex – the chance that a single skeleton would survive to be discovered by humans 66 million years later. The answer: about 1 in 80 million. That is, for every 80 million adult T. rex, there is only one clearly identifiable specimen in a museum.

This number highlights how incomplete the fossil record is and allows researchers to ask how rare a species could be without disappearing entirely from the fossil record.

Beyond calculating the T. rex fossilization rate, our new method could be used to calculate population size for other extinct species.


Jurassic Quest roars into The Pavilion at Star Lake through Father's Day

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The current act showing at The Pavilion at Star Lake in Burgettstown is a big one.

Jurassic Quest Drive-Thru, a touring dinosaur exhibit, opened Friday. From their cars, guests get to see larger-than-life dinosaurs and other animals from that time period.

The attraction runs through Sunday, June 20.

Cars need to keep their speed at 5 miles per hour.

&ldquoWe are a covid-friendly, family-friendly experience, and when you stay in your cars, you stay safe from the dinosaurs,&ldquo said &ldquoPrehistoric&rdquo Nick Schaefer,&rdquo a show tour guide. &ldquoWe also have some dinosaurs people can interact with.&rdquo

As they drive through the course, they can text questions about what they are curious about.

The animal figures are made of steel and silicone. They include details from feathers to scales to tails and teeth.

They move and roar, loudly.

They&rsquove been created with input from paleontologists, who are scientists who study the history of life on Earth through the fossil record, the American Geosciences Institute said.

&ldquoChildren with sustained interests in dinosaurs typically do better in STEM (science, technology, engineering and math) careers,&rdquo Schaefer said. &ldquoIt creates interest in learning about chemistry and molecular science and geology and biology and astrology.&rdquo

Jurassic Quest is the largest exhibition of life-size, moving dinosaurs in North America, according to its organizers.

Guests experience Cretaceous, Jurassic and Triassic Periods.

Jurassic Quest has been shown in 34 states and Canada. It sold more than one million tickets in 2019.

Jurassic Quest Drive-Thru is a touring dinosaur exhibit that has been attended by more than 2.5 million people, according to organizers.

The Tribune-Review announced it was coming to Western Pennsylvania in April.

The show features over 70 life-like dinosaurs including the Tyrannosaurus Rex, known as T-Rex, Spinosaurus and Triceratops. They&rsquore displayed in realistic scenes.

There are also baby dinosaurs.

The tour lasts about an hour.

Attendees receive a free photo in their vehicles set against a dinosaur backdrop.

Cost is $49 per vehicle. They can be purchased here.

Hours are 9 a.m. to 9 p.m. Saturdays 9 a.m. to 8 p.m. Thursdays, Fridays, and Sundays 1 p.m. to 8 p.m. Wednesdays closed Mondays and Tuesdays.

JoAnne Klimovich Harrop is a Tribune-Review staff writer. You can contact JoAnne at 724-853-5062, [email protected] or via Twitter .

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That evolutionary lineage might explain why T. rex had tiny arms.

D. Finnin/American Museum of Natural History A full-scale cast of the T. rex fossil skeleton on display in the AMNH’s Hall of Saurischian Dinosaurs.

For earlier tyrannosaur relatives with smaller bodies, these tiny arms were long enough to grasp prey or pull food into their mouth.

“The earliest tyrannosaur species had arms that were perfectly proportioned,” Erickson said.

He said he thinks T. rex’s puny arms were vestigial – a body part or organ that no longer serves a function but is nevertheless retained (kind of like a human’s appendix or wisdom teeth).


What’s next

This study might lead to other hidden facts about T. rex biology and ecology.

For instance, we might be able to learn whether T. rex populations fluctuated up and down with Triceratops – similar to wolf and moose predator and prey relationships today. However, most other dinosaurs do not yet have the incredibly rich data from decades of careful fieldwork that allowed our team to tally up T. rex.

If scientists want to apply this powerful technique to other extinct animals, we’ve got some more digging to do.


Watch the video: What Did The T-Rex REALLY Sound Like? (December 2021).