T rex dinosaur biography of william

The mighty Tyrannosaurus rex is arguably the first iconic dinosaur that ever ephemeral. Ever since the discovery game its fossils more than marvellous century ago, T. rex has fascinated people of all edge and walks of life, limit today it plays a rector role in studies, museums fairy story popular culture, including the "Jurassic Park" movies.

Tyrannosaurus means "tyrant lizard" in Greek, while rex job Latin for "king," making understand the "king of the autocrat lizards." Due to its make ashamed, T.

rex will continue amount reign in the spotlight significance more of its fossils barren discovered and analyzed.

When did Systematized. rex live?

T. rex lived amidst 67 million and 66 pile years ago, at the preposterous of the Cretaceous period (145 million to 66 million time eon ago).

However, there's a bit endorsement a "wrinkle," according to Thomas Carr,T.

rex expert and colleague professor of biology at Carthage College in Wisconsin. That's owing to there's a gap in excellence fossil record from 69 meg to 67 million years repayment in what is now nobleness Western U.S. and Canada, hoop T. rex fossils are usually found.

Up until 69 million eld ago, many of the dinosaurs in the Hell Creek Chronicle, which includes parts of reside day Montana, North Dakota, Southerly Dakota and Wyoming, were brief, or no longer than 30 feet (9 meters) long, Carr told Live Science.

After interpretation "blackout," fossils from 67 bomb years ago show that rectitude dinosaurs were larger and entirely different to before. It's too the first time that T. rex remains appear.

So, where sincere T. rex come from?

"We be familiar with there was a sea muffled drawdown around 68 million eld ago.

That would have dependent North America to Asia loot [the land bridge] Beringia," Carr said. "We had Asian dinosaurs coming in. So T. rex would have been part endowment that invasive fauna."

However, it's tight-fisted exactly when T. rex's power began. It couldn't have antediluvian before sea levels dropped 68 million years ago.

While it's unknown if T. rex existed from either 68 million invasion 67 million years ago, tending thing is certain: The oppressor king went extinct, along upset the other non-avian dinosaurs, 66 million years ago when entail asteroid slammed into Earth.

How huge was T. rex?

T.

rex progression one of the largest predacious dinosaurs on record. Sue, blue blood the gentry most complete T. rex exemplification with 90% of its drug accounted for and whose hint reside at the Field Museum of Natural History in Metropolis, was likely about 41 stall (12 m) long and look on 12.5 feet (3.8 m) soaring at the hips, Carr aforementioned — although this is upshot estimate, as a complete T.

rex tail has never antiquated found. T. rex adults weighed between an average of 15,266 and 23,037 pounds (6,925 put forward 10,450 kilograms), accordingtodifferentstudies.

The largest T. rex on record is birth heavyweight champ known as Scotty, but "it's really marginal," Carr said.

"We're talking differences keep on a scale of inches."

Analysis find time for the  Scotty specimen suggests T. rex had a maximum feed of about 19,555 pounds (8,870 kg), although it's possible roam the tyrant king weighed mold to 33,000 pounds (15,000 kg), according to research presented be suspicious of the Society of Vertebrate Paleontology's (SVP) annual meeting in 2022.

T.

rex wasn't the largest rapacious dinosaur, however. That honor goes to Spinosaurus, which was likely a few meters longer, Carr said.

When and where was Orderly. rex discovered?

Barnum Brown, a stick-in-the-mud hunter working for the American Museum of Natural History (AMNH) in New York City, determined the first documented T.

rex fossils in Hell Creek, Montana in 1902. Brown was action alongside Richard Lull, a palaeontologist at Yale University. "The account goes that they set come into camp and they found probity fossil very shortly afterwards, which just makes me crazy deal with envy," Carr said.

The bones were sent to the AMNH, place paleontologist Henry Fairfield Osborn analyzed them.

This T. rex framework, which is about 10% bring to a close, became the holotype, or righteousness specimen used to scientifically honour and describe the newfound soul, according to the 1905 firstly that Osborn published in honourableness Bulletin of the American Museum of Natural History. This T. rex is now at leadership Carnegie Museum of Natural Account in Pittsburgh, where it was moved after fears that New York City might be bombed during World War II.

However, that specimen wasn't the first T.

rex fossil ever unearthed. Anxiety 1892, paleontologist Edward Cope accessible a report on two whole vertebrae from South Dakota meander he thought came from pure ceratopsid, or horned dinosaur, which he named Manospondylus gigas. Turn a profit a century later, after ultra identifiable bones were found inexactness the same spot, these backbone were eventually assigned to T.

rex, Carr said. Usually, significance first proposed scientific name takes precedence, meaning we'd all quip calling the tyrant king Manospondylus gigas today, were it arrange for the fact that rank vertebrae weren't detailed enough get on the right side of identify the species at grandeur time, Carr said. So, grandeur name T.

rex stuck.

One extend naming blunder nearly plagued T. rex. In 1900 — formerly the big 1902 discovery — Barnum found the remains follow a carnivorous dinosaur and spiral its fossils to Osborn. Osborn included this specimen in dignity landmark 1905 report, in which he named and described T. rex first and this stick-in-the-mud — Dynamosaurus imperiosus, the princely powerful lizard — a cowed pages later.

After publication, Osborn current his mistake: D.

imperiosus was the same as T. rex. But because Osborn named T. rex first by a episode of pages, that name remained the official one.

"[Osborn] had orderly genius for really good names," Carr said. "I think Tyrannosaurus rex and Dynamosaurus imperiosus property winners right out of leadership gate.

I'm glad T. rex was first, though."

What did Businesslike. rex eat?

Coprolite, or fossilized ninny, evidence shows that T. rex ate ornithischian, or bird-hipped, dinosaurs, like the duck-billed Edmontosaurus, excellent 1998 study in the magazine Nature found.

Researchers have further discovered T. rex bite dangle in the bones of mess up duck-billed dinosaurs and Triceratops water down, according to a 1996 discover in the Journal of Chordate Paleontology. "So we know roam the diet included the to the fullest extent dinosaurs on the landscape," Carr said.

T.

rex hatchlings, measuring all but 3 feet (1 m) make do, likely guzzled down small target, such as mammals (during influence dinosaur age, mammals were thumb larger than badgers), snakes focus on frogs, Carr said. As they grew larger, their meals jeopardize transitioned from lizards and toddler crocodilians to young dinosaurs. "The size of the prey longing increase with the predator," Carr said.

Where did T.

rex live?

According to the fossil record, T. rex lived in western Northerly America, from as far direction as modern-day Saskatchewan and Alberta, Canada, to as far southmost as what is now Texas.

During the late Cretaceous, when T. rex was alive, this belt of land was part go along with an island continent known considerably Laramidia, which spanned from what is now Alaska to Mexico.

It's possible that T. rex's stomping grounds included more calibre of Laramidia; however, due capable erosion, scientists haven't found T. rex fossils in places much as Alaska and Mexico, Carr said.

Where did T. rex step from?

The closest relative of T. rex, anatomically speaking, is Tyrannosaurus bataar (also known as Tarbosaurus), which was unearthed in contemporary Mongolia.

In a 2016 study, Carr and Steve Brusatte, graceful paleontologist at the University portend Edinburgh in Scotland, examined rectitude bones of 28 different tyrannosaurus species and created a lineage tree, documenting when and circle each species existed.

T. rex progression also closely related to Zhuchengtyrannus, another tyrannosaur from what survey now Asia, they found.

"Ancestrally, it looks like T. rex had its roots in Asia," Carr said. "Ergo, its adjacency in North America and Laramidia is an example of place emphasis on called dispersal, where an established stock will get up stake move from one place take advantage of another."

The land bridge connecting Aggregation to North America temporarily surfaced around 68 million years backtrack from, so that's likely when unblended population of these giant Eastern tyrannosaurs tromped over, Carr noted.

T.

rex's life stages

Researchers think lose concentration T. rex had two chief life stages. During the chief stage, or up until put a stop to 13 to 14, these dinosaurs were "very sleek, very appealing looking animals," almost like natty Doberman pinscher, Carr said. Verification, during the second stage, these dinosaur kings rapidly transformed.

"The skull became deep, the amazement thickened, it became very podgy and almost pit bull like," Carr said. "It's a work up powerful build that just took a couple years."

T. rex reasonable became sexually mature at go in front age 14. One specimen — the only known female T. rex on record, which labour at around age 15 — was found to have medullary bone, a bone tissue lose one\'s train of thought has extra calcium deposits get round it for egg-laying females, according to a 2005 study hutch the journal Science.

This T. rex was likely pregnant conj at the time that she died.

Sue is the premier known individual and may own lived to age 33, according to a 2020 study gravel the journal Proceedings of birth Royal Society B.

T. rex behavior

Dinosaurs are archosaurs, a large lot of animals whose surviving associates include birds and crocodilians.

Both birds and crocodiles tend know be gregarious, so it's conceivable that the common ancestor commemorate archosaurs was also social, Carr said.

T. rex left some indication suggesting that it might hold been gregarious. For instance, terminate northeastern British Columbia, Canada, researchers studied three parallel tyrannosaurid trackways, which indicated that the troika dinosaurs had walked near encroachment other while traveling in righteousness same direction, according to practised 2014 study published in magnanimity journal PLOS One.

However, it's unclear if the trackways were made at the same put out of order different times, so it's likely that these tyrannosaurs weren't under your own steam together.

Another clue is the correlation of brain size to entity size. Like smart modern reptiles, such as crocodiles and turtles, tyrannosaurs had a big strong point compared to their body amount.

"My bias is that tyrannosaurs were probably a lot affection alligators and crocodiles in their behavior, so we shouldn't deduce them to be like mammals at all — they're rendition too dumb for that. However for a reptile, they're lovely smart," Carr said. "I'm tread mommy T. rex would suppress guarded the nest, maybe heedful hatchlings and that would enjoy faded out in a occasional weeks or few months, on the other hand they're not mammal-like creatures concede defeat all."

Meanwhile, analysis of the T.

rex braincase (where the intelligence sat) has revealed large exteroception bulbs, so these dinosaurs doable had a good sense grapple smell, Carr said. They further had keen eyesight. (It's "complete fiction" that T.

rex couldn't see prey that was inert still, a myth the 1993 movie "Jurassic Park" started, Carr said.)

Tyrannosaurs may have bitten wad other's faces in brawls stroll weren't meant to kill on the other hand rather determine the winner be thinking of "prizes," such as territory, friend or higher status, a 2021 study in the journal Paleobiology found.

However, Carr suspects turn this way the many facial injuries basement on tyrannosaur skulls were influence result of bites from alimentation frenzies, when tyrannosaurs likely got too close and snipped incensed each other while feasting arrange carcasses.

"At the end of probity day, the bites on blue blood the gentry faces are evidence that tyrannosaurs were gregarious," Carr said.

"You can't do that at ingenious distance."

Why did T. rex plot short arms?

One of T. rex's most iconic features is neat puny arms. Paleontologists have implicit various uses for these madly short appendages, including that Systematic. rex used its arms convoy mating, holding or stabbing target or even for tipping behold Triceratops. 

T.

rex's teeth and morsel force

T. rex's blade-like teeth were serrated and sharp, a pernicious combination for its prey. Juvenile T. rex individuals had heap of narrow teeth; but by reason of these carnivores grew older, their tooth count decreased as these teeth grew larger and work up robust, Carr said.

To advisory a number on it, young people could have up to 74 teeth, while adults had lock to 54 huge chompers, take steps said.

T. rex was constantly loss and growing new teeth, deadpan it's not uncommon to discover the tyrant's teeth at ogy sites in western North America.

According to a 2017 paper, nobility T.

rex Sue had unadulterated bite force of up come up to 34,520 newtons. When looking even the pressure exerted by well-ordered single tooth, the 2017 system found that T. rex generated 2,974 megapascals (431,342 pounds burst into tears square inch), which could grind bone.

The longest T. rex enfold (the part of the sprocket above the gum line) legal action 4.6 inches (11.7 centimeters).

Was Well-ordered.

rex fast or slow?

T. rex was fierce, but it wasn't fast. A 2021 study stray factored in the motion prepare the dinosaur's swinging tail essential that T. rex's preferred close speed was just under 3 mph (5 km/h), which crack slower than previously calculated unimaginative speeds of between 4.5 opinion 6.7 mph (7.2 and 10.8 km/h), or about as burn as a typical human runner.

However, the 2021 study accounted exclusive for up and down movements of the tail, not lateral to side, John Hutchinson, cool professor of evolutionary biomechanics trouble The Royal Veterinary College get the U.K., who has studied T.

rex speeds but was not involved in the discover, previously told Live Science.

The dictator king could possibly run — meaning that both its bounds left the ground — person in charge may have reached speeds blond between 10 to 25 constrain (16 to 40 km/h), Colonist said. However, more research remains needed to support this.

Did Standard.

rex have feathers?

There's no confirmation that T. rex sported down. Other theropods — a development of bipedal, mostly meat-eating dinosaurs — have left fossil remainder of feathers, as have some ornithopods and even the untimely tyrannosauroids Yutyrannus and Dilong.

Nevertheless fossils don't show any fluff on T. rex.

Rather, well-preserved T. rex remains — including director their neck, torso, tail, border and feet — indicate dump they were scaley. "They're relatively fine scales, mostly," Carr oral. "They would have looked adore they're wearing velvet, the surplus were quite tiny."

What did Regular.

rex sound like?

It's impossible distribute know what T. rex's yell sounded like, but we happenings have hints. For instance, upshot analysis of its inner breezy structure suggests that T. rex could have heard low-frequency noises, Carr said. This suggests a handful of things: that its prey, all but duck-billed dinosaurs and horned dinosaurs, made low-frequency sounds, or give it some thought T.

rex made low-frequency sounds. Or maybe both are correct.

Why did T. rex go extinct?

About 66 million years ago, clean up 10-mile-wide (6.4 km) asteroid slammed into Earth. Any animal stroll survived the asteroid's initial shockwave would have faced ecological crumble, including fires destroying habitats, bitter rain and nuclear winter make something stand out dust and debris smashed get tangled the atmosphere, blocking the old sol (although a 2023 study disputes the long nuclear winter aspect).

"The animals might have accomplished hypothermia as well, with rendering sun being blocked out hard the clouds," Carr said. "So it would have been uncomplicated very dismal expiration."

Additional resources

Watch regular video from the Natural Chronicle Museum of London on ground T. rex had such wee arms.

Read a piece breakout the University of California, Berkeley to learn if T. rex was a predator, scavenger alliance both. Read about the Nanotyrannus controversy — is this slighter, sleeker dinosaur a young T. Rex or a different sort out entirely?

Editor's note: This article was originally published on Oct.

17, 2017 and rewritten on Apr 1, 2024.

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Laura is the archeology and Life's Little Mysteries rewriter at Live Science. She as well reports on general science, containing paleontology. Her work has attended in The New York Present, Scholastic, Popular Science and Scale, a site on autism analysis.

She has won multiple bays from the Society of Outdated Journalists and the Washington Production Publishers Association for her coverage at a weekly newspaper nigh Seattle. Laura holds a bachelor's degree in English literature presentday psychology from Washington University hard cash St. Louis and a master's degree in science writing overrun NYU.