Birds of terror, what you didn’t know about these extinct birds

Birds of terror, we are talking about giant birds with a maximum height of three meters and about 150 kilos in weight. These characteristics allow it to easily become the largest predator in South America, but the available data indicate that it began to move northward five million years ago, with the incomplete Panamanian state and still in education.

Bird of Terror History

The Great American Interchange was one of the most important events already recorded, with a wide movement of wildlife, which developed from north to south, and vice versa. According to experts, carnivores from the North triumphed over predators from South America, but for several million years, there was an exception to that rule: Phorusrhacidae, also known as “terror birds”, whose remains were found in Florida and Texas.

History tells us that after the separation of the supercontinent Gondwana, South America became an isolated environment that resulted in a completely different wildlife than the rest of the planet. It is estimated that the first visits to the northern South American continent occurred 7.3 million years ago, long before the formation of the Isthmus of Panama, but it was only with its final appearance (2.8 million years ago) that the American Grand Exchange was established.

The agile carnivores (canids, cats, bears and various rodents) traveled south and had great success, thanks to better preparation for domestic competition, climatic adaptation and wider development space, while the south to the north, only marsupials and xenarthrans (tatus, sloths, tamanduas) managed to succeed in their new land. However, there is an asterisk in the record: Birds of Terror, Phorusrhacidae.

Some species under the terror bird family were necrophagous, but the rest definitely fell into the predator category. The bones of their skulls were fused, so they used the combination “beak” as if it were a hammer. The spikes ended in a hook, ideal for piercing, splitting and tearing prey, and the strength of their legs was such that they could break bones.

Experts believe that the modern descendants of the caryamid of terrorist birds, inherited from their ancestors ??a certain type of hunting, which take their with the beak and whip the ground to death. Imagine a three-meter bird to do so.

For the time being, the terror birds were the most successful carnivores in the north, even in Florida and Texas, but that’s where they found a lot of competition, courtesy of wolves, wild dogs and the famously sleepy tigers. But the most important aspect contributing to their demise was climate change (in connection with the recent Ice Age), which limits their effective invasion of less than three million years.

Main data for this species:

  • Lived in what is now South America
  • Lived during the Middle Miocene Period
  • Weighed as much as a panda bear
  • It could run faster than a horse
  • Could not fly
  • It was carnivorous

Like prehistoric predators

About three million years ago, volcanism brought the Isthmus of Panama to the surface, and the continents of North and South America were joined. But before that, South America remained isolated for about 150 million years, since it separated from Africa at the beginning of the Cretaceous period.

During all that time, the fauna of South America was very particular; especially in relation to mammals. South American mammals belonged mainly to the marsupials, xenarthrans, sloths, tatus and tamanduas, and several groups of ungulates have now disappeared.

But the apex of the ecological pyramid was occupied by animals that evolved into a form reminiscent of tyrannosaurs and other large carnivorous dinosaurs of the previous era. They were large, hulking, bipedal, with strong, narrow, curved, sharp claws on their legs.

Although quite large mouth with sharp teeth have a strong curved beak, instead of a muscular tail probably have a tail feathers, and instead of weapons have wings, but very short, withered wings, which do not gain flight. They are forusracids, known as terror birds, large carnivorous birds that cannot fly. They are between one and three meters tall, can weigh more than 350 kilograms and almost all are fast. Some species reach up to 70 km (43 miles).There are two groups of giant circidian forus: brontornithines and forusracines. The first, older, has very strong legs and are slow animals. The second survived until the eradication of the group, and is softer, with thinner legs.

Among the brontornithines, the most famous and the largest is Brontornis, the predominant predator in Patagonia during the Miocental period between 20 and 5 million years ago. Brontornis reaches 2.80 meters in height and weighs between 350 and 400 kilos. He is not a fast runner, chases underground, and is also an opportunistic grappler; thanks to his enormous size, he can steal change from smaller predators.

Although some recent studies of the anatomy of Brontornis suggest that it was not a bark forus but a giant spirit. a giant carnivorous duck, yes. But not all paleontologists agree with this classification. Paraphysornis is another brontornithine, somewhat smaller, that lived in southeastern Brazil 23 million years ago. About this species, there is no doubt, it is really a forusracid. It is two meters tall, with a skull sixty centimeters long.

Among the forusracines, the giant forusracid giant, is Phorusrhacos Longissimus, the first species was discovered by this group and named. Its discoverer was the Argentine naturalist Florentino Ameghino, who in 1887 described a piece of jaw that he identified as belonging to a xenarthro mammal.

The name, which means “wrinkle-bearing,” refers to the rough surface of the jaw. A few years later, in 1891, it was recognized as a bird. Phorusrhacos, 2.5 meters tall and weighing 130 kilograms, lived in forests and grasslands in Patagonia between 20 and 10 million years ago.

The skull of Phorusrhacos is sixty centimeters long, half of which corresponds to the beak, robust and addicted. The wings, although atrophied, are not useless; they function as short arms ending in claws, with which the Phorusrhacos can bring down its prey. What we don’t know for sure is how he killed them. Either he picked them up with his beak and slammed them repeatedly on the ground, as rains do today, or else he pierced the victim’s skull with a claw, killing him instantly.

It presumably used its large size and speed to pursue its target. Scientists think that snoring its would hold its claws and then grab it in its jaws. He would then repeatedly slam the small mammal to the ground until he killed it. Then he could feed himself as his free time.


Diatryma, extinct, giant flightless bird found as fossils in early Eocene rocks in North America and Europe (the Eocene Epoch lasted from 57.8 to 36.6 million years ago). Diatryma grew to a height of approximately 2 1More complete specimens of a fourth species are known from North America , which had previously been classified in the distinct genus Diatryma.

Many scientists now consider Diatryma to be so similar to the other Gastornis species that it should also be included in that genus. A fifth species, also previously classified in its own genus, is known from China. Diatryma grew to a height of about 2.3 meters. Its small wings were not used for flight, but its legs were massively built up.

Their highly reliable apomorphic anatomy prevents any group of allocation birds, especially since no relatives are close to surviving today. In modern times, they were placed with the set “Gruiformes” including. But in the 21st century, these birds are considered gallanaries or “fowl” in the same super-orderly hens and seabirds.

Ironically, Hebert’s original assessment, which perceived similarities to Anseriformes in the original shinbill, would be much more correct than any later placement. Also, given that galloanosaurs are known to originate in chalk, it is not difficult to explain how such a gigantic bird could develop 10 million years after the dinosaurs died out as a non-avian.

Types of Terror Birds


During the cenozoic era developed a large number of descendants of dinosaurs, birds. In cenozoic era was different diversified bird animals, prepared for life in almost all parts of the world. Within this large group of different birds arose neorniterna (new birds).

This group is characterized by having a horny nose, no teeth, bones fused to the limbs and an effective four-chambered heart, suitable for fast muscle movements performed during flight. Birds measured up to three meters in height and called terrorism as their main species were raptors that were at the top of the food pyramid and among the most terrible carnivores of their time.

Neornitanerna, including giant birds, bizarre waterfowl, and also others very different than those that exist today, are now extinct. Their extinction coincided with the expansion of man.

The neornites, also called ornithura, is a subclass of extant or extinct birds, with or without teeth in the jaws, tail with some vertebrae, the last welded on a pygostyle, collapsed I sternum or flat, metacarpals welded and without claws on their wings.

They are grouped into four supercomputers, odontognaths and ichiornites are extinct; and living creatures of paleognaths, prop plates or runners. impennates; and neognaths or carinates.


One of them was the huge carnivorous Titanis (giant), was a forusrácido or touch of terror. A bird flygelös of South America, which is about 2.5 m long, had a large head, powerful curved bills and long legs with strong claws and highly destructive.

This terrifying bird fed on mammals that inhabited the plains four million years ago, such as, for example, the Hipparion, a primitive horse. The Titanis, surprisingly agile and with powerful legs capable of catching even the fastest prey, could hunt a 150 kg prey, like this horse.

The remains of Titanis were found in North America. Despite its South American origin, this bird migrated northward as North America merged with South America, and is the only large predator to make the journey in the opposite direction, apparently surviving until almost 400,000 years ago.


In Argentina, remains of another relative of the Tinanis were found, the Andalgalornis, with a deadly beak and a very velóz, lived approximately 50 million years ago. The Andalgalornis has its descendants in Argentina. Its closest relatives are the chuñas, which inhabit northwestern Argentina.

Andalgalornis was a Sumerian terror bird, small in size and had the largest beak in comparison. It had a huge, curved eagle, about the size of a horse’s head, which served to strike ponds and cause damage to the areas used to attack the sides, back and neck.

In these areas, the upper part of the curvature fits better between the legs and could immobilize the animal’s legs, causing this to fall. Its beak was not designed for cutting meat, but for breaking bones. Its wings were rather faded and practically unusable for hunting, but probably had some utility, perhaps, as a small aid when traveling on hillsides.

The hind legs were slender and thin, but the thigh muscles were very strong and allowed the bird to reach speeds of more than 70 km (43 miles).This animal gathered in small groups during mating time, consisting of males and females. The males fought with their spikes and with the claws of their hind legs to obtain the right to mate, to ensure that future generations would be stronger.


Paraphisornis was also found in Brazil, with its complete skeleton.

Paraphysornis was a large flightless bird. Although it was a terrible predator, there were predators for carnivorous cubs. Paraphysornis was one of the most exultant members of the terror birds and was closely related to Physornis and Brontornis. (See Article: Agapornis Personata)

Due to its large size and heavy conditions, Paraphysornis probably relied on trekking tactics to surprise change rather than running towards it. Although this does not mean that Paraphysornis did not endanger the change.

Terror bird videos

In Argentina

It was a large carnivorous bird that was discovered by Florentino Ameghino in the spring of 1887 in Santa Cruz, Argentina. Although it was given the name Phorusrhacos, a name meaning “rag-bearer” it is officially known as the terror bird, and that it must have been a bird that terrorized mammals living in South America during the Middle Miocene or about 12 million years ago.

When it was first named by Florentino Ameghino, he gave it a name that he didn’t end up with, which is the norm was to end up with the name of a fossilized bird because that’s the Greek word for “bird.” And that was not the case. It’s an oversight Initially, he didn’t think the terror bird was a real bird. He assumed it was a megafaunal mammal. However, he was wrong and it was recognized as a bird.

Looking at the images of the terror bird will quickly give you an idea of why that bird got its name. When alive, it was about 8 meters tall and weighed about 300 pounds. He had a very large head that was equipped with a very sharp beak, he had clawed wings and large claws on his feet. He would have been feared by any small mammal that stumbled upon him. Especially since he loved to eat small mammals.

One of the most interesting facts about the terror bird is that, although it was unable to fly, it could run at incredible speeds. Scientists estimated that it was capable of spinning at approximately 35 miles per hour. That’s faster than a horse! Just one more tool in their arsenal of weapons that would have scared that bird.

The largest forusracid and the largest known bird of prey was discovered in Patagonia in 2006 and described in 2007. It is Kelenken, named after a fearsome Tehuelche mythology spirit that takes the form of a giant bird of prey. Kelenken fossil remains of a skull and fragments of a foot and a leg, was discovered at the Comallo train station, near the town of Bariloche, by William Oscar Aguirrezabala and the Paleontological Museum in Bariloche.

Kelenken lived about 15 million years ago, measuring more than three meters tall and weighing more than 160 kilos. The skull is 70 cm long, almost equivalent to the upper 46, narrow and beaked like an eagle. Despite its size, it is a fast runner; Adults reach 50 km.

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