Prehistoric Earth was a dangerous place - and the creatures of that time had to be equally deadly. Check out the...
Fossils of some specimens such as Llallawavis scagliai show that the birds could hear low frequencies, meaning that they may have been able to track prey by the rumble of their footsteps. 3D reconstruction of the skulls showed that they would have been fairly solid but also quite rigid. This in turn suggests that terror birds didn't grab and shake prey—instead they drove their hooked beak into a victim, dragging it back out to cause massive rending injuries with the point.
While terror birds are extinct, you might be interested to know that the seriema birds of today are their descendants!
Humans and many other animals have active lungs that provide oxygen to the blood in our circulatory system. In contrast, Arthropods have a simple respiratory system that relies on trachea (tubes running from the skin to the innards) and passive "book lungs" to provide tissues with direct access to oxygen. Researchers theorize that this simple respiratory system would not be able to provide enough oxygen for a giant arthropod to survive under modern conditions.
Livyatan melvillei reached around 17m, putting it in the same ballpark as the modern squid-hunting sperm whale - though equipped with a much larger and more powerful bite. This whale is thought to have shared the waters with megalodons and possibly even competed with them for food.
There are significant advantages to being a massive predator, but none of them were enough to counter famine. Cooling sea temperatures 12 million years ago led to a scarcity of the large prey that Livyatan melvillei depended on, and the leviathan faded into history.
This creature was an apex predator in the Early Devonian. Fossil remains indicate well-developed compound eyes that would grant excellent vision, whilst the claws would offer a lethal offensive weapon. If the two species had ever crossed paths, it is likely that these armored aquatic beasts would have dismantled a human in short order.
Some are rather surreal, like Araripesuchus rattoides, the 3ft long "rat crocodile" that dug for grubs and plants with a set of buckteeth in the lower jaw. Others, such as Kaprosuchus saharicus, were clearly dangerous predators. This species was a 20ft long meat eater that possessed an armored snout that may have been slammed into victims like a battering ram and three vicious sets of protruding blade-like interlocking teeth to butcher cornered prey. With a snorkel-like snout, this monster could hide in water and sprint bipedally on land.
- Terror Birds
- Monstrous Millipedes
- Leviathans
- Giant Sea Scorpions
- Bipedal, Sprinting Crocodilians
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| Terror birds could have easily made a meal of a human... (Michael_Pointner) |
1. Terror Birds
Found in America around 3.5 million years ago, terror birds were mighty carnivores that reached 10ft in height and sported a hooked beak to rend flesh. Fossils found in France and Switzerland indicate that they also had a presence in Europe.Fossils of some specimens such as Llallawavis scagliai show that the birds could hear low frequencies, meaning that they may have been able to track prey by the rumble of their footsteps. 3D reconstruction of the skulls showed that they would have been fairly solid but also quite rigid. This in turn suggests that terror birds didn't grab and shake prey—instead they drove their hooked beak into a victim, dragging it back out to cause massive rending injuries with the point.
While terror birds are extinct, you might be interested to know that the seriema birds of today are their descendants!
2. Monstrous Millipedes
Reaching around 2.6 meters in length and boasting an estimated weight of 50 kilograms, Arthropleura is the largest land-living arthropod ever discovered on Earth. This massive millipede lived during the Carboniferous (around 300 million years ago), and it probably owed its size to comparatively high oxygen levels. Carboniferous Earth was inundated with plants, and much of the carbon now in our atmosphere was locked inside vegetation—over 26% of the atmosphere was oxygen rather than the 21% of today.Humans and many other animals have active lungs that provide oxygen to the blood in our circulatory system. In contrast, Arthropods have a simple respiratory system that relies on trachea (tubes running from the skin to the innards) and passive "book lungs" to provide tissues with direct access to oxygen. Researchers theorize that this simple respiratory system would not be able to provide enough oxygen for a giant arthropod to survive under modern conditions.
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| The modern, less dangerous version... (Anonymous) |
3. Leviathans
They weren't subtle when they named Livyatan melvillei. An ancient ancestor of the modern sperm whale, fossil remains from these titanic creatures have been found in Peru. With a 3-meter-long skull adorned with 12cm diameter and 36cm length teeth, this creature is thought to have hunted other, lesser whales.Livyatan melvillei reached around 17m, putting it in the same ballpark as the modern squid-hunting sperm whale - though equipped with a much larger and more powerful bite. This whale is thought to have shared the waters with megalodons and possibly even competed with them for food.
There are significant advantages to being a massive predator, but none of them were enough to counter famine. Cooling sea temperatures 12 million years ago led to a scarcity of the large prey that Livyatan melvillei depended on, and the leviathan faded into history.
4. Giant Sea Scorpions
Though referred to as a sea scorpion Jaekelopterus rhenaniae lacked a poisonous stinger - though, in fairness, it hardly needed one. A chelicera (claw) of the species found in Germany reached 46cm in length and (when cross-referenced with other fossils) it suggested an estimated body length of 2.5m.This creature was an apex predator in the Early Devonian. Fossil remains indicate well-developed compound eyes that would grant excellent vision, whilst the claws would offer a lethal offensive weapon. If the two species had ever crossed paths, it is likely that these armored aquatic beasts would have dismantled a human in short order.
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| Worrying enough in water... (Bergadder) |
5. Bipedal, Sprinting Crocodilians
Modern crocodiles are deadly ambush predators, lunging out of the water and dragging a meal into a river to drown. It seems that this wasn't always the case, though, as researchers have discovered bipedal-crocodilian tracks in Korea and bipedal crocodilian skeletons in Africa.Some are rather surreal, like Araripesuchus rattoides, the 3ft long "rat crocodile" that dug for grubs and plants with a set of buckteeth in the lower jaw. Others, such as Kaprosuchus saharicus, were clearly dangerous predators. This species was a 20ft long meat eater that possessed an armored snout that may have been slammed into victims like a battering ram and three vicious sets of protruding blade-like interlocking teeth to butcher cornered prey. With a snorkel-like snout, this monster could hide in water and sprint bipedally on land.
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