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Why Did Brachiosaurus Have A Bump On His Head?

When you see pictures of the Brachiosaurus, the first thing you notice is its giant size. It’s a sauropod just from the first look. The next thing you notice is the unusual stance. The dinosaur’s back legs are bent, and it stands on tiptoes with its front feet planted solidly on the ground. Why did this dinosaur have such a strange posture? Then you notice its long neck and small head, which has a well-defined bump on it. Why was there a bump with two holes on its head?

As a general rule, scientists agree the bump on the head of the Brachiosaurus served as nostrils for the dinosaur. The nostrils are similar to other sauropods and dinosaurs in general. According to new research, the position of the nostrils, forming a bump on the dinosaur’s head, should likely be positioned closer to the front of the nose.

Some questions still puzzle scientists today. For instance, they know that Brachiosaurus had an unusually high stance, possibly because it needed to reach up into trees to feed itself. He also used his long neck for defense against predators who dared hunt him! But without a living specimen, we only have fossils to help determine more about how this dinosaur lived and the exact type of anatomy it had.

Let’s take a closer look at that bump on the Brachiosaurus’ head.

Why Did Brachiosaurus Have Nostrils on Top of The Head?

Understanding the structure of nostrils is crucial to determining how a species lived. The body should correlate with an animal’s lifestyle, and paleontologists can take hues from different parts of fossils.

There are reasons to believe that Brachiosaurus lived on earth and smelled its food with a snout. The land animal also breathed via its huge nostrils to sustain its high-rate metabolism. Nostrils tell how a creature smelled and breathed. 

Brachiosaurus-with-nasal-bump-on-head-AdventureDinosaurs-1

These two functions are more important than reconstructing its cosmetics.

More studies will tell more about this species, and we’ll hopefully unearth more fossils with finer details. Then, we can finally reconstruct this giraffe-like species with more accurate cosmetics. 

For now, let us get more details on the nostrils.

The peculiar nose on top of Brachiosaurus heads is subject to heated debates among paleontologists. 

This species confused scientists with big nasal openings on top of its peculiar sauropod skeleton.

Brachiosaurus was a neosauropod with bony nasal openings. The nostrils were large and on top of the skull.

Previously, scientists thought that Brachiosaurus was a swamp herbivore with its head. However, evidence from fossils and living relatives of dinosaurs suggest otherwise.

Lawrence Witmer was among the first and most impactful paleontologists to reject the theory. He disputed that the brachiosaurid nose was an amphibian trait. Additionally, he suggested that the position of the bump forming the nostrils should be positioned closer to the tip of the nose. (Source)

Brachiosaurus really could not do as well in water as on land. Its body was filled with air sacs, which could have made it buoyant and unstable in water. Moreover, its limbs were not broad enough to propel its massive size through muddy swamps.

Brachiosaurus also had a narrow chest, which could not be sufficient for underwater breathing.

This creature did not have a snorkel-like breathing system. 

Paleontologists observed the pattern of blood vessels in Brachiosaurus skulls and ruled out the possibility of a snorkel. 

The anatomy of crocodilians, amniotes, and birds also suggests that this giraffe-like dinosaur had a front snout.

Anatomy specialists can determine if ancient creatures had trunks. They study the skull and the distribution of blood vessels. 

They can also tell if a species had a snout or a snorkel by observing other bone structures. (Source)

What Special Features Did The Brachiosaurus Have?

Brachiosaurus was a highly unusual dinosaur. It lived 150-156 million years ago and resembled gigantic giraffes. 

In 1903, paleontologists thought that Brachiosaurus was the largest dinosaur. But bigger sauropod fossils proved otherwise as time passed.

Scientists and dinosaur fans refer to Brachiosaurus as the armed lizard. They didn’t even consider their belief that Brachiosaurus was the biggest ever dinosaur when naming it. 

YouTube Video About the Size Comparison of Brachiosaurus to Other Dinosaurs

YouTube Video by Amazing Viz which shows comparisons of dinosaurs including the Brachiosaurus. Video starts at 3:03 – AdventureDinosaurs

They took a deep interest in its fore legs, which were longer than its hind legs.

Brachiosaurus was a sauropod, and it had relationships with other long-necked dinosaurs. Its gigantic size allowed it to generate high body temperatures. 

It could maintain body temperatures of 45°C or 113°F.

This species had an egg-shaped head and nostrils at the top. The size of its nasal openings in the skull indicates that Brachiosaurus had an elaborate sense of smell. 

The exceptionally tall and long herbivore browsed treetops, eating ferns and conifers.

It had chisel-like teeth that cut off the top leaves and branches of trees. It never chewed. Instead, it swallowed the vegetation whole for its gut to digest.

Brachiosaurus was like all sauropods in its enormous size and gigantothermic body heat. 

But it was unlike all sauropods in its limb structures. Its longer forelimbs inclined its back. It also had a long neck, which made it look like an 80-foot giraffe. (Source)

The longer forelimbs also gave this dinosaur species an exceptionally high stance. It could tower up to 26 meters (50 feet) high and make an imposing defensive stance. 

Its tail was short and thick, which improved its balance.

The tail was almost useless for defense reasons. But, it prevented Brachiosaurus front constant falls. A fall could easily shutter the egg-shaped head of the dinosaur.

For its massive size, Brachiosaurus had a relatively small head. The dinosaur had low intelligence compared to the carnivores that dared hunt it.  

The exact angle and flexibility of the neck relative to its body are unknown. However, scientists believe flexibility was integral for its survival.

Moreover, this dinosaur breathed via an elaborate air sacs system. Its respiratory system was like that of modern birds or all ancient sauropods. 

The species enjoyed a unidirectional flow of oxygen, which supported its massive demand for fresh air. After all, giganthotherms required high rates of metabolism.

Brachiosaurus Phylogeny and Where Its Fossils Were Found

Paleontologists initially thought that Brachiosaurus and the Tanzanian Giraffatitan were the same species. The Giraffatitan species was much bigger and from Sub Sahara Africa. Brachiosaurus fossils have only been discovered in the Morrison Formation.

The North American fossil-rich formation gave telling clues about the species. Scientists could even deduce how Brachiosaurus interacted with other dinosaurs.

YouTube Video About Brachiosaurus – The Giant of Jurassic

YouTube Video by Cleaver Rex which explains about the Brachiosaurus and the role it played in North America during the late-Jurassic period – AdventureDinosaurs

The formation was most likely a semi-arid environment. It had dry seasons and very wet spells. Studies on fossils discovered in the area suggest Brachiosaurus were a rare species when they still roamed North America.

For example, it only had 12 specimens out of a fossil-rich locality with 98 Diplodocus, 112 Apatosaurus, and 179 Camarasaurus.

It is easy to tell that Brachiosaurus was a sauropod. It is the longest North American dinosaur yet, with its neck helping it to reach 82 feet at a young age. (Source)

The body temperature estimate also confirms Brachiosaurus was like other sauropods. It was a giganthotherm. 

The animal had to cool off the heat, and it evolved several mechanisms to regulate the heat. For example, it reduced its metabolism as it aged.

Paleontologists with specialized expertise can determine the body temperature of ancient species. They only need to analyze the isotopes taken from fossils. 

They measured the ratio of atoms and neutrons in Brachiosaurus teeth. From the findings, they estimated that Brachiosaurus body temperature averaged at 107°F.

Studies on Brachiosaurus fossils indicate the species could be much taller than 82 feet. The fossils that estimated an average of 82 feet were from relatively young dinosaurs. 

The youngster could have averaged 62 tons in weight.

Parting Shot

The Brachiosaurus is one of the most interesting sauropod dinosaurs ever discovered. Unlike other sauropods, this dinosaur sported an unusual neck position. An enlarged bump on its head, which served as nostrils, grew to enormous sizes and had very large necks and forelimbs. In terms of size, it was the largest sauropod found in North America.

It is amazing how diverse the sauropod species are. Titanosaurs, Dicreaosaurs, Prosauropods, and Sauropods all had their differences and similarities. One thing is for sure; the Brachiosaurus is distinctive thanks to the bump on its head, and I hope this article has helped provide some insight as to what that bump was all about.