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The Ultimate Comparison Between a Brontosaurus and a Brachiosaurus

Brontosaurus Vs. Brachiosaurus
Brachiosaurus

The Brontosaurus and Brachiosaurus were both one of the most gigantic dinosaurs that walked the surface of the earth many millions of years ago.

They were extremely similar, which is why are carefully assessing them today: Brontosaurus vs. Brachiosaurus!

Othniel Charles Marsh, Public domain, via Wikimedia Commons

The Brontosaurus and Brachiosaurus are two enormous herbivorous dinosaurs from the late Jurassic era, which people frequently confuse for one another. That’s a common misunderstanding because they have very similar appearances. Both of them possessed very long necks and small heads. However, they differ significantly in several ways.

Each had very different shapes and stances. Moreover, a Brontosaurus could roar even louder than a canon. The Brontosaurus was a solitary species, whereas the Brachiosaurus was a herd animal. Although both were nothing short of gigantic, the Brachiosaurus was much bigger and heavier in comparison to the Brontosaurus.

Comparing Brontosaurus and Brachiosaurus:

Here is a table that highlights the main differences between them:

FeaturesBrontosaurusBrachiosaurus
Alternative NameThunder lizardArm lizard
PeriodLate Jurassic period, 157 to 145 million years agoLate Jurassic period,161 to 145 million years ago
SizeHeight: 28 feet
Length: 72 to 85 feet
Height: 40 feet
Length: 60 to 70 feet
Weight33,000 poundsUp to 128,000 pounds
Body ShapeElephant-like, long & thin neck, small head, heavy body, long whip-like tail.Giraffe-like, small head, extremely long neck, muscular tail.
NareNo nareLarge nare over the skull, between eyes
TeethBroad and tough teeth, resembled spatulas or spoonsPencil or pegs-shaped teeth, comb-like arrangement of teeth
LimbsFront legs slightly shorter than hind legsFront legs larger and longer than hind legs
DietAte vegetation at ground levelHigh browser – ate vegetation from top of trees
HabitatOpen plains and marshy areasOpen plains and forests
Social BehaviourSolitary animalsHerd animals

Introduction To Brontosaurus

Brontosaurus Vs. Brachiosaurus
Brontosaurus. Image by Scott Greer via Unsplash

The Brontosaurus was a big sauropod dinosaur. It existed between the late Jurassic and early Cretaceous times, between 163.5 million and 100.5 million years ago. It is among the most well-known dinosaurs. Brontosaurus translates as “thunder lizard” in Greek.

They were believed to be a closely-related species of Apatosaurus. As a result, they were classified as a member of the Apatosaurus. However, they were identified as a separate genus later because they possessed various distinct traits.

Brontosaurus Species:

They had three species:

· Brontosaurus Excelsus

· Brontosaurus Yahnahpin

· Brontosaurus Parvus

Introduction To Brachiosaurus

The Brachiosaurus was a big giraffe-like dinosaur. It had a small skull and a lengthy neck. Brachiosaurus means “arm lizard” in Greek. It was given this name because its limbs were extremely long. They weighed more than 50 tons and were 40 to 50 feet tall.

They existed between 155.7 million and 150.8 million years ago, during the middle to late Jurassic era. The Brachiosaurus had short hind legs and long front legs, making it easier to keep its neck upright. As a result, it is regarded as one of the world’s tallest dinosaurs.

Brachiosaurus Species:

They had the following species:

· Brachiosaurus Alataiensis de Lapparent

· Brachiosaurus Zbyszewski

· Brachiosaurus Lusotitan

Key Differences Between Brachiosaurus and Brontosaurus:

Brachiosaurus
Brachiosaurus. Image by Elenarts via Depositphotos.

It is their outward appearance that most distinguishes the Brachiosaurus and Brontosaurus. Brachiosaurus dinosaurs were similar to giraffes and were among the Earth’s tallest dinosaurs to have ever existed.

On the other hand, the brontosaurus dinosaurs were similar to elephants in many aspects. It was one of the world’s longest dinosaurs.

Here is a more detailed breakdown of the key differences between both species:

Brontosaurus vs. Brachiosaurus: Size

YouTube video
Brontosaurus – The Story of the Thunder Lizard” Source: YouTube, Uploaded: Ben G Thomas

Size is the primary distinction between the Brachiosaurus and Brontosaurus. Both of these dinosaurs are large in their rights. However, the Brontosaurus was considerably longer, whereas the Brachiosaurus was relatively taller. The Brontosaurus could reach a height of 28 feet and grow to amazing lengths of between 72 and 85 feet – a result of their long tail and neck. However, the Brachiosaurus had the upper hand due to its height, it measured 40 feet tall and between 60 and 70 feet long.

Brontosaurus vs. Brachiosaurus: Weight

long neck dino
Image by Creative Vix via Pexels

The maximum weight of a brontosaurus was 33,000 pounds. But the Brachiosaurus weighed a lot more. Impressively, they reached 128,000 pounds. You can get an idea of their massive weight if you compare them to African bull elephants.

An African bull elephant weighs approximately 12,000 pounds. It is currently the heaviest mammal living on Earth. The Brachiosaurus was heavier than 10 African elephants. So, you can imagine how much heavier they would have been.

Brontosaurus vs. Brachiosaurus: Body Shape

how many long neck dinos
Image by Vaibhav Pixels via Unsplash

The forelegs of the Brachiosaurus were longer, and their physique had a sharp downward slope. But the Brontosaurus was inclined slightly in the opposite direction by nature. It made them appear hunched. The necks of the Brachiosaurus formed a modest “S” curve. Moreover, they had strong tails.

Unlike the Brachiosaurus, Brontosaurus did not carry its neck as high. They carried their necks out in front of them instead. Their neck was virtually parallel to the ground. As a result, they required a very long tail to balance off their long neck. Their tails were long and slender, with a whip-like shape at the end.

Brontosaurus vs. Brachiosaurus: Nare

Nares are big nasal airways. They are situated atop the head of the Brachiosaurus. It appears like a huge bulge in front of their eyes. The nares are thought to be placed there due to the presence of air sacs.

These sacs were also found down the neck. There was a connection between these air sacs and the lungs. They were there all the way down the base of their neck. Brontosauruses did not have these big nares.

Brontosaurus vs. Brachiosaurus: Teeth

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By S. Manitkoon, U Deesri, B. Khalloufi,T. Nonsrirach, V Suteethorn, P Chanthasit, W Boonla, & E Buffetaut – “A New Basal Neornithischian Dinosaur from the Phu Kradung Formation (Upper Jurassic) of Northeastern Thailand”, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=134500867

The teeth of the Brontosaurus were big and strong. They looked like spoons or spatulas. Compared to other sauropods, their tooth structure enables them to chop and chew the plant’s pieces more easily.

The Brachiosaurus had teeth that resembled pencils or pegs. These teeth had blunt triangular edges and were long and slender with a comb-like pattern. It implies that the Brontosaurus was unable to rip through hard plant matter.

Brontosaurus vs. Brachiosaurus: Limbs

long neck dino media
Toy Dinosaurs. Image by Nate Dewaele via Unsplash

Comparing the size of their limbs is another notable variation between the Brontosaurus vs. Brachiosaurus. On the Brachiosaurus, the front legs were longer than the back legs; meanwhile, the front legs of the Brontosaurus were shorter than the back legs.

The Brontosaurus had a single, substantial claw on each forelimb. Meanwhile, the Brachiosaurus had claws on the first three toes of each foot, with the front claw’s bone having a small bend to it. 

Brontosaurus vs. Brachiosaurus: Neck Posture

The neck of the Brontosaurus was short; therefore, they were able to lower and bring it closer to the ground easily. Moreover, they were linked together and twirled around the neck bone, which served to support their huge body.

The longer neck of the Brachiosaurus was held high and they adopted a giraffe-like posture as a result. This dinosaur’s cervical vertebrae enabled it to bend. As a result, it can easily lift its head to eat from large trees.

Brontosaurus vs. Brachiosaurus: Ribs and Vertebrae

The neck ribs of the Brachiosaurus were extremely lengthy. They ran along the back of the neck, crossing numerous vertebrae before them. These bony structures had their ends connected to neck muscles. There was a tiny shoulder hump between the third and fifth dorsal vertebra.

In comparison to other sauropod dinosaurs, the rib cage was deep. The neck vertebrae of Brachiosaurus had a deep bifurcation. There were 15 cervicals and ten dorsals in the spine and tail. Approximately 82 caudals and five sacrals were also present. There were ten dorsal ribs on each side of the body.

Brontosaurus vs. Brachiosaurus: Diet

Both the Brontosaurus and the Brachiosaurus were herbivores and they consumed a variety of flora and plants. However, their diet differed in terms of source of food. Because the two dinosaurs were physiologically different, they sourced their food differently. The Brachiosaurus was a high browser. It was so tall that it could eat from the tops of trees. As a result, the Brachiosaurus typically consumed foliage between 16 and 30 feet high. On the other hand, the Brontosaurus consumed food at ground level. 

Brontosaurus vs. Brachiosaurus: Feeding Pattern

Image via Wikiemedia Commons

The Brachiosaurus had a taller, more upright neck structure, allowing it to consume the vegetation growing at tall heights. Their teeth were strong and wide so that they could slice through the entire plant and break up the fragments.

The posture of the Brontosaurus’ neck was horizontal, making it suitable for eating low vegetation rather. Although its height also allows it to access high places and eat from trees. They didn’t chew their food like dinosaurs. Instead, they had gizzard stones to break rough and fibrous plant bits.

Brontosaurus vs. Brachiosaurus: Social Behavior

The Brachiosaurus is typically thought to coexist with other members of their species. They consume all of the local plants as a herd while feeding. Then, they move on to the next one.

Brontosaurus is said to be a more solitary herbivore. It often wanders in herds but generally walks alone when eating.

Brontosaurus vs. Brachiosaurus: Habitat

Brachiosaurus was widespread in terms of presence throughout the world. They had a significant population. In contrast, Brontosaurus was present in the western portion of the northern hemisphere.

Brontosaurus lived in a desert-like environment. It coexisted in the same habitat as dinosaurs, frogs, fish, and other extinct animals. They are sadly no longer in existence. The only remains of dinosaurs are fossils and lifelike artificial dinosaurs.

Brontosaurus vs. Brachiosaurus: Reproduction

Both the Brontosaurus and Brachiosaurus reproduce by laying eggs. But strangely, the young were typically no larger than an adult goose today. Sauropods were initially quite small. However, they expanded quickly.

Most sauropod eggs weighed less than 11 pounds when laid (five kilograms). Despite this, they grew to be adults 10,000 times heavier in only around three decades. No other land mammal has ever had a yearly weight rise that significant.

Brontosaurus vs. Brachiosaurus: Discovery

The first brontosaurus fossil was found in North America in 1874. Paleontologist Othniel Charles from the United States first characterized it.

The first Brachiosaurus fossil was discovered in the Colorado River Valley in Western Colorado. In 1903, American paleontologist Elmer S. Riggs described it for the first time.

Brontosaurus vs. Brachiosaurus: Weaknesses

The mobility and attack rate of a brontosaurus are both quite slow. They can become caught behind cliffs due to their enormous size. When wounded, they’ll also make an effort to flee. So, even if it won’t fight back, players underneath it still risk getting hurt.

It should also be noticed that their tail strikes to the left. This can be avoided by fast strafing in the opposite direction. Even with the most basic weapons, like the bow, it is simple to kill a Bronto. 

Frequently Asked Questions:

YouTube video
“Brachiosaurus Scene – Welcome to Jurassic Park” Source: YouTube, Uploaded: Best Clips

Are the Family Groups of Brachiosaurus and Brontosaurus the Same?

They are not members of the same family group, despite the fact that they were both sauropods. Brontosaurus belonged to the Diplodocidae family. It included some of the world’s longest sauropods.

Meanwhile, the Brachiosaurus was a member of the Brachiosauridae family. They were among the tallest sauropods on the Earth. As you can see, both of these animals belonged to different species.

Were Brachiosauruses and Brontosauruses Dangerous?

Despite their huge size, the Brachiosaurus and Brontosaurus were quite calm species. Both of them were large herbivores. There weren’t many predators around, which means they didn’t have to fight with other animals. It proves that they live quite peacefully.

The Brontosaurus’ very long tail was likely its most dangerous feature. It was long and narrow and spun with great force. 

Did the Brontosaurus and Brachiosaurus Live Side By Side?

The Brontosaurus and Brachiosaurus shared the same habitat and existed in the late Jurassic era in what is now North America.

Their existence spans the same number of years. As a result, it’s easy to deduce that they lived together. Both are thought to have lived for approximately 100 years.

Why Were the Brachiosaurus and Brontosaurus Called Arm Lizard And Thunder Lizard?

Brachiosaurus was also called “arm lizard” due to the length difference between their front and hind legs. The term “thunder lizard” refers to Brontosaurus because the Greek word for Brontosaurus is “thunder lizard.”

Did the Brontosaurus Live in Water?

According to historical theories, big dinosaurs like the Brontosaurus spent most of their time in the water. They reasoned that they could not have supported their weight on land because the dinosaurs’ bodies were so large. Therefore, they would have needed the assistance the weightlessness water provides. 

However, it was eventually argued and proven that they lived on land. They stayed on land most of the time but did wade in the shallows occasionally.

Did They Have Any Predators?

Image Via Wikimedia Commons

There weren’t many predators for the Brachiosaurus, primarily because of their size and long neck. However, other dinosaurs, like the Allosaurus, occasionally hunted down and killed some large dinosaurs in their vicinty.

Adults were probably too huge to take down typically, so perhaps the main victim was children. The Brontosaurus protected its long neck and shoulders from predators during the late Jurassic era. Its head extended higher than the largest carnivores. A similarity between the two dinosaurs is that neither had many predators.

How did Brachiosaurus Defend Itself?

The dinosaur Brachiosaurus was big enough to fend off most predators. It was marginally bigger than the largest carnivores of the time, such as the Allosaurus. If the Brachiosaurus encountered any dangers, its long tail would serve as its main line of defense.

Similar to the Brontosaurus, it would have been wielded like a whip. However, compared to other sauropods, its tail was shorter. As a result, its range would be limited. Additionally, they had thick, leather-like skin. However, the sharp teeth of smaller theropods would still be able to penetrate it.

Who Went Extinct First?

The Brontosaurus became extinct near the end of the Jurassic epoch, although the cause is unknown. However, the Brachiosaurus most likely perished along with the rest of the dinosaur species. Supposedly, a significant meteorite collision destroyed most of the dinosaurs. 

How Did the Brachiosaurus and the Brontosaurus Grow So Big?

Image by Charles R Knight via Wikimedia Commons

Studies on their bones reveal that the creatures initially acquired up to two tonnes annually. Their pace of growth slowed just before they turned 20, but the beasts continued to grow bigger and bigger. It is estimated that they reached sexual maturity at ten years old. 

How Many Brains Do a Brontosaurus and Brachiosaurus Have?

As far as we presently know, no dinosaur had a second brain. Here, there are two related problems. The first is that the spinal cords of numerous dinosaurs had observable extensions around their limbs.

It is a characteristic that made a lasting impression on the vertebrae’s neural canal size. The brain of the Brachiosaurus was small, making it doubtful that it was particularly intelligent.

The Bottom Line on Brontosaurus vs. Brachiosaurus

The Brontosaurus and Brachiosaurus were both giant sauropod dinosaurs, even in dinosaur terms. However, their physiology, dietary habits, and other traits were different. The primary distinction between the Brontosaurus and Brachiosaurus was their size. As a result, their postures differed and also affected their feeding patterns. The Brontosaurus was one of the largest dinosaurs known to have lived on Earth.

In addition, the Brachiosaurus had longer front legs than back legs. In contrast, the Brontosaurus had somewhat shorter front legs and longer back legs. 

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