Nightmarish Animals That You Should Be Glad Are Extinct

Overview

The video presents extinct animals whose size, anatomy, or predatory adaptations might have made them frightening. Its descriptions are delivered humorously, and some claims—such as the suggestion that Megalania was venomous—are presented without detailed supporting evidence.

Animals Featured

Megalania (Varanus priscus)

A large Australian monitor lizard related to the Komodo dragon, Megalania is said to have reached about 18 feet long and weighed more than 1,300 pounds. It lived until roughly 50,000 years ago, when Indigenous people were already in Australia. The video suggests human activity may have contributed to its extinction.

The video also connects Megalania to the Aboriginal Australian legend of the Wawi, although reports that the Wawi had six legs do not match Megalania’s anatomy. It claims Megalania had venom that interfered with blood clotting.

Terror Bird

The subtitles name this animal “Forest Rhekode,” possibly as an auto-caption error. The video describes a flightless South American predator about 8 feet tall and around 800 pounds. It reportedly could run at an estimated 31 mph and had a powerful beak and sharp talons.

According to the video, terror birds later migrated into North America during the Great American Interchange, after the Isthmus of Panama formed a land connection.

Gigantopithecus

A large, herbivorous ape known from fossils found in southern China, Gigantopithecus is estimated in the video to have stood about 10 feet tall. Its size estimates rely on teeth and jaw fragments rather than complete skeletons.

The video also discusses the unsupported “Bigfoot Giganta Hypothesis,” which proposes that Gigantopithecus survived in the forests of the Pacific Northwest.

Anomalocaris

An early marine predator described as a large, shrimp-like animal more than 6 feet long. It had overlapping body plates, spiny front appendages, stalked eyes with numerous lenses, and likely swam actively. It probably used its appendages and mouth to capture prey.

Arthropleura

A giant land invertebrate that lived in what is now Europe and North America roughly 345–290 million years ago. It could reach about 8.5 feet in length and had many pairs of jointed legs and protective body plates.

The video says the initial interpretation of Arthropleura as a predatory, centipede-like animal was later revised. Scientists now consider it more likely to have been a herbivorous, millipede-like creature.

Dunkleosteus

A large armored fish that lived around 370 million years ago. Its jaws had bony plates shaped into cutting edges that could sharpen against one another. The video says it could rapidly open its jaws to draw prey in by suction and bite through heavily armored animals.

A 2016 study is mentioned in connection with scrape and puncture marks on Dunkleosteus armor. These marks may have been made by larger individuals, suggesting cannibalism.

Pentacopterus

An ancient aquatic arthropod named after a Greek warship. It is described as a large, swimming, scorpion-like animal with paddle-shaped body parts and numerous clawed arms for catching and tearing prey. Its fossils were found in Iowa, which the video says was a marine environment at the time.

Helicoprion

A large, shark-like cartilaginous fish that may have reached around 40 feet in length. Its distinctive feature was a spiral whorl of teeth in its lower jaw.

The video explains that cartilaginous fish have skeletons made primarily of cartilage rather than bone, as in modern sharks, rays, and skates.

Phoberomys pattersoni (“Ratzilla”)

A giant extinct rodent from Venezuela’s ancient Orinoco River Delta, about 8 million years ago. It could exceed 8 feet in length and weigh up to 1,700 pounds. Although herbivorous, it had large, needle-like teeth.

Researchers and Sources Mentioned

• Ralph von Koenigswald: Anthropologist credited in the video with discovering Gigantopithecus in 1935.
• A 2016 study: Cited for evidence of scrape and puncture marks on Dunkleosteus armor; the researchers and publication are not named.
• Guinness Book of World Records: Cited in connection with Arthropleura’s record as the largest land-based invertebrate.
• Unnamed Bigfoot researchers: Mentioned in the discussion of the proposed Gigantopithecus–Bigfoot connection.