10 Animals That Once Ruled The Earth But Are Now Forgotten.

10 Animals That Once Ruled The Earth But Are Now Forgotten: Time Capsules Of The Past!

Did you know that there were once animals that ruled the earth but are now forgotten? 

Our planet’s incredible diversity of life has seen species come and go throughout history.

While dinosaurs often steal the spotlight, other animals once dominated the earth but have been overshadowed by their prehistoric counterparts. 

These forgotten creatures had unique features and adaptations that allowed them to thrive in their respective environments. 

A few fascinating examples of animals that were once rulers are Meganeura, Thylacoleo, Andrewsarchus, Titanoboa, etc.

While these animals may no longer exist, their imprint on the natural world is still felt today. 

Exploring the stories of these forgotten rulers of the earth allows us to appreciate the incredible diversity and richness of our planet’s history.



Meganeura Overview And Characteristics

Meganeura is an ancient species of dragonfly that once ruled the Earth during the Carboniferous period, approximately 310 to 325 million years ago. 

This giant insect had a wingspan of up to 2.5 feet, making it one of the most giant insects to have ever existed. 

Meganeura had a slender body and large compound eyes, which allowed it to have excellent vision and hunt prey efficiently.

Despite its intimidating size, Meganeura was harmless to humans as it primarily fed on other insects and small vertebrates. 

Its diet consisted of creatures like tiny amphibians and, possibly, the primitive ancestors of reptiles. 

Meganeura had a unique ability to fold its wings while resting, contributing to its evolutionary success.

Reasons For Meganeura’s Extinction

The decline and eventual extinction of Meganeura can be attributed to several factors:

  • Decrease in oxygen levels: During the Carboniferous period, oxygen levels in the atmosphere were much higher than today. 

However, as oxygen levels gradually decreased over time, Meganeura’s large size and high oxygen demand became unsustainable, limiting its survival ability.

  • Changing climate: The Earth underwent significant climate changes during the Carboniferous period, transitioning from moist swampy environments to drier areas. 

These changes may have impacted Meganeura’s habitat and food sources, leading to a decline in population.

  • Competition: As other insects and animals evolved, competing for resources and habitats, Meganeura faced increased competition for prey and territories. 

This competition and the challenges posed by changing environmental conditions further contributed to its decline.

While Meganeura may be forgotten today, its existence is a significant reminder of the diverse and intriguing creatures that once roamed the Earth millions of years ago.



Thylacoleo Description And Physical Attributes

Once a powerful predator, Thylacoleo, also known as the “marsupial lion,” ruled the forests of Australia around 30,000 years ago. 

Standing at about 75 centimeters tall, this carnivorous mammal possessed a strong build with a muscular body. 

It had sharp retractable claws, a unique feature for a marsupial, which aided in climbing trees and capturing prey. 

The Thylacoleo had a unique set of razor-like teeth, specialized for slicing through flesh. 

Its robust jaw and powerful bite force made it a formidable hunter.

Factors That Led To The Extinction Of Thylacoleo

The disappearance of Thylacoleo can be attributed to several factors:

  • Loss of habitat: The expansion of humans into the region caused deforestation and a significant loss of the marsupial lion’s natural habitat.
  • Competition for food: As more human settlements were established, the competition for prey increased. 

The introduction of large predators, such as dingoes, also threatened Thylacoleo’s food sources.

  • Climate change: Climate changes, including shifts in temperature and rainfall patterns, affected the availability of food for Thylacoleo. 

These fluctuating conditions likely contributed to its decline.

  • Human hunting: Aboriginal communities may have hunted Thylacoleo for food and fur, further impacting the population.

Unfortunately, due to a lack of written records, much of what we know about Thylacoleo is based on fossils and scientific speculation. 

Despite its fascinating nature and powerful presence in ancient Australia, Thylacoleo has become one of Earth’s forgotten rulers.



Overview Of Andrewsarchus And Its Features

Andrewsarchus, known as the “giant predator,” was a unique mammal that roamed the Earth during the Eocene epoch, approximately 45 to 36 million years ago. 

Despite its name suggesting a dinosaur-like creature, Andrewsarchus was a mammal, the largest in its family.

This ancient creature was estimated to be about 13 feet long and weighed around 1,000 pounds, making it one of the largest terrestrial mammal carnivores ever known. 

Its physical features included a large head, long limbs, and sharp teeth, indicating that it was a fierce predator. 

Some theories suggest that Andrewsarchus might have had a scavenger-like behavior due to its jaw structure.

Reasons For Extinction Of Andrewsarchus

Although it was a formidable predator of its time, Andrewsarchus eventually became extinct. 

The exact reasons for its extinction remain uncertain, but scientists speculate on several factors that could have contributed to its downfall.

One theory is that competition for resources significantly affected their extinction. 

As the environment changed and other animals evolved and diversified, Andrewsarchus may have struggled to find sufficient prey, leading to its decline.

Another contributing factor may have been climate change. During the Eocene epoch, the Earth experienced significant environmental shifts, including global cooling. 

These changes likely affected the habitats and food sources available to Andrewsarchus, potentially driving them towards extinction.



Titanoboa was an enormous snake that once ruled the Earth but is now largely forgotten. 

Its name means “titanic boa,” a fitting description for this prehistoric predator.

Titanoboa’s Size And Physical Characteristics

Titanoboa was the most giant snake ever with a length of up to 42 feet and weighing over a ton. 

Its weight and length surpassed even the most enormous pythons and anacondas of today. 

This monstrous serpent had a girth of over three feet and could easily swallow crocodiles whole.

Titanoboa roamed the Earth approximately 60 million years ago during the Paleocene epoch. 

Its massive size was made possible by the warm climate of this period. 

The high temperatures allowed the snake to have a more efficient metabolism and grow to incredible proportions.

Probable Causes Of Titanoboa’s disappearance

As the Earth’s climate changed and cooled, the creatures that thrived in the warm temperatures, including Titanoboa, began to decline. 

Around 58 million years ago, the global temperature started to drop, causing the decline of the rainforests that the snake relied on for its survival. 

With the loss of their habitat and the decrease in suitable prey, Titanoboa eventually went extinct.

Another factor that may have contributed to Titanoboa’s disappearance is the competition from other predators. 

As the climate changed, new predators emerged, and the ecosystem became more diverse. 

This would have placed additional pressure on Titanoboa to adapt to new conditions, which it was ultimately unable to do.

Although Titanoboa is now forgotten by most, its fossils and the scientific discoveries it has led to continue to fascinate paleontologists and provide valuable insights into the Earth’s ancient climate and ecosystems.



Description And Features Of Glyptodon

Glyptodon was a massive, prehistoric creature that once roamed the earth. 

It belonged to the same family as armadillos and appeared similar to a giant armadillo on steroids. 

This fascinating animal was covered in a thick, bony armor, which protected it from predators. 

It measured about 10 feet long and could weigh up to 2 tons, making it one of the largest land mammals of its time.

Glyptodon had a domed shell of around 1,000 bony plates, offering excellent defense against predators. 

Its short legs and stout tail allowed it to move relatively slowly. Its diet consisted mainly of plants and grasses.

Factors Contributing To The Extinction Of Glyptodon

Despite its impressive size and armored protection, Glyptodon eventually became extinct. 

Several factors likely contributed to its demise.

  • Climate Change: The earth experienced significant climate fluctuations during the Pleistocene epoch. 

The changing environment and the loss of suitable habitats may have disrupted the food chain, leading to a scarcity of resources for Glyptodon.

  • Overhunting: Human arrival in the Americas is believed to have coincided with the decline of Glyptodon. 

Native tribes would have hunted these large animals for their meat and shells, ultimately decimating their population.

  • Competition: The arrival of new predators, such as the saber-toothed cats and American lions, would have posed a significant threat to Glyptodon’s survival. 

The competition for resources may have further limited their chances of survival.

Although Glyptodon walked the earth for thousands of years, its existence eventually ended. 

Today, it remains a fascinating creature of the past, reminding us of the diverse array of animals that once ruled the earth but are now forgotten.


Dunkleosteus Overview And Unique Characteristics

Dunkleosteus, a prehistoric fish that lived during the Late Devonian period around 380-360 million years ago, was one of the most fearsome predators of its time. 

It was an armored fish with a length of up to 33 feet and weighed around 4-6 tons. 

What made Dunkleosteus truly remarkable was its powerful jaws, which could exert a force of up to 1,100 pounds per square inch, enabling it to crush the armor of its prey with ease.

This ancient creature had no teeth but possessed two large bony plates that acted as sharp cutting edges. 

Its body was covered in thick armor-like plates, providing excellent protection from other predators. With its ferocious appearance and exceptional hunting abilities, Dunkleosteus dominated the oceans and was a top predator during its existence.

Possible Reasons For Dunkleosteus’ Extinction

The exact reason for Dunkleosteus’ extinction remains uncertain, but scientists propose a few theories. 

One possibility is that changes in the Earth’s climate led to a decrease in the availability of food sources for Dunkleosteus. 

As its prey became scarce, the population of Dunkleosteus may have declined, ultimately leading to its extinction. 

Another theory suggests that competition with other marine predators could have played a role in its demise.

Additionally, the Late Devonian period was marked by significant environmental changes, including a drop in sea levels and the oxygen content in the oceans. 

These changes may have negatively impacted the survival of Dunkleosteus and its ability to thrive in its habitat.

Although Dunkleosteus is now forgotten and extinct, it serves as a reminder of the diverse and fascinating creatures that once ruled the Earth’s oceans. 

Their incredible adaptations and impact on the ecosystem offer valuable insights into the history of life on our planet.



Entelodon, also known as “The Hells Pig,” was a prehistoric mammal that once ruled the Earth. 

Despite its fierce and intimidating appearance, this forgotten creature is rarely mentioned in discussions about ancient animals. 

Let’s delve into the fascinating world of Entelodon and uncover why it is now forgotten in the annals of history.

Entelodon’s appearance and characteristics

Entelodon was a member of the family Entelodontidae, which lived during the Eocene and Oligocene epochs, approximately 56 to 33.9 million years ago. 

It had a robust build, with a height of about six feet and jaws armed with powerful, sharp teeth. 

Its massive head, stocky body, and strong limbs were evidence of its predatory nature.

Despite sharing similarities with modern-day pigs, Entelodon was not closely related. Instead, it was more closely related to hippos, whales, and carnivores. 

This unique combination of features sets Entelodon apart from other ancient mammals.

Likely Causes For The Extinction Of Entelodon

While the exact reasons for the extinction of Entelodon remain unclear, several possibilities have been suggested. 

Changes in the Earth’s climate during the Oligocene period could have influenced the availability of food sources, impacting the survival of Entelodon and other large mammals.

Additionally, competition from other predators might have contributed to the decline of Entelodon. 

The emergence of more specialized and efficient predators could have threatened its existence. 

The evolutionary success of these competing species and the decline in their food sources could have led to the extinction of Entelodon.

Despite its disappearance from the Earth millions of years ago, Entelodon’s legacy lives on through paleontological discoveries. 

While this ancient creature may be forgotten, its unique characteristics and place in Earth’s history remind us of the diversity and intrigue of prehistoric life.



When we think of animals that once ruled the Earth, we often imagine dinosaurs or other prehistoric creatures. 

However, there are lesser-known animals that are equally fascinating and deserve recognition. One such animal is the Moa.

Moa Description And Size

The Moa was a flightless bird that was native to New Zealand. 

These magnificent birds stood at an awe-inspiring height of up to 12 feet and weighed as much as 500 pounds. 

They had long, slender necks, powerful legs, and no wings. 

They were herbivores and were able to reach leaves in trees and shrubs and played an important role in the ecosystem.

Factors Contributing To The Extinction Of Moa

Unfortunately, the Moa is now extinct, and several factors contributed to their demise. 

The arrival of humans in New Zealand brought along hunting and deforestation, ultimately leading to the extinction of the Moa. 

The indigenous Maori people hunted these birds for food and used their feathers and bones. 

Furthermore, the introduction of predatory mammals, such as rats and dogs, also played a significant role in the decline of the Moa population.


Megalodon Overview And Impressive Traits

The Megalodon, known as the “big tooth,” was a prehistoric giant shark that ruled the Earth’s oceans millions of years ago. 

With an estimated length of about 50 to 60 feet, the Megalodon was one of the largest predators in history. 

Its immense size and powerful jaws with rows of gigantic teeth made it a fearsome creature.

The Megalodon’s teeth were about seven inches long, much larger than any shark species today. 

These teeth were undoubtedly its most impressive feature, allowing it to catch and devour large prey easily. 

Its massive body and sharp senses ensured it could dominate the prehistoric oceans.

Reasons For The Disappearance Of Megalodon

Despite its impressive reign, the Megalodon mysteriously vanished from the Earth’s waters around two million years ago. 

Scientists have proposed several theories to explain its disappearance, but the reason remains debatable.

One theory suggests that a decline in the Megalodon’s primary food source, such as whales, may have led to its extinction. 

Others believe changes in ocean temperatures or competition from other predatory species could have played a role. 

Another hypothesis is that the Megalodon’s large size made it more susceptible to environmental changes, making it unable to adapt to a shifting ecosystem.

Regardless of the cause, the Megalodon’s absence left a void in the marine world. 

Although modern-day sharks have their own unique adaptations, none can match the awe-inspiring presence and power of the Megalodon.

In conclusion, the Megalodon was a remarkable creature that once dominated the Earth’s oceans. 

Its massive size and extraordinary teeth set it apart from all other sharks. 

Although its disappearance remains a mystery, the Megalodon legacy remains a reminder of the Earth’s fascinating prehistoric past.

The Gigantic Elephant Bird

The Gigantic Elephant Bird
The Gigantic Elephant Bird

The Gigantic Elephant Bird: The Massive Prehistoric Shark

The Gigantic Elephant Bird, also known as Aepyornis maximus, was an incredible creature that roamed the Earth millions of years ago. 

It was a massive flightless bird that stood up to 10 feet tall and weighed about 1,000 pounds. 

The Gigantic Elephant Bird is believed to be the heaviest bird that ever lived.

The bird was native to the island of Madagascar and only became extinct around 1,000 years ago. 

The Gigantic Elephant Bird had a long, slender neck, a small head, and tiny wings that were too small to fly. 

It was primarily herbivorous, feeding on plants and fruits.

Reasons For Extinction Of The Gigantic Elephant Bird

There are several theories as to why the Gigantic Elephant Bird became extinct. 

One theory suggests that human activity plays a significant role. 

The arrival of humans on the island introduced hunting, habitat destruction, and the introduction of invasive species that competed with the Gigantic Elephant Bird for resources.

Another theory proposes that climate change and environmental changes also contributed to their extinction. 

As the climate changed and the forests gave way to grasslands, the Gigantic Elephant Bird lost its habitat and food sources, leading to a decline in population.

The Gigantic Elephant Bird is an intriguing species that once roamed the Earth. 

While it is now extinct, its legacy lives on in the form of fossils and scientific research. 

Studying these incredible creatures helps us understand the Earth’s rich history and the delicate balance of nature.


While they may be forgotten now, these animals once roamed the Earth as dominant rulers of their respective ecosystems. 

From the majestic Titanoboa to the hulking Megalodon, these creatures played a vital role in shaping the natural world as we know it today. 

Reflecting on their existence allows us to marvel at the diversity and grandeur of our planet’s history.

Reflecting on these forgotten animals helps us appreciate the incredible diversity that once existed on Earth. 

It also serves as a reminder of the importance of conservation efforts to protect the species that remain today.

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