evolution
Horses Started Dog-Sized
The first horses (Eohippus) were only 30 cm tall—about the size of a fox! They had four toes and lived 55 million years ago. Horse evolution is one of the best-documented in paleontology.
Welcome to Prehistoric World
Discover the fascinating creatures that once roamed our planet
Featured Creatures
Featured Creatures
Tribrachidium
Proterozoic
Tribrachidium is one of the strangest creatures to ever exist! Living during the Ediacaran period about 558-555 million years ago, this bizarre disc-shaped organism had three-fold symmetry — a ...
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Tyrannotitan chubutensis
Cretaceous
Tyrannotitan, meaning "tyrant titan," was one of the largest meat-eating dinosaurs ever to exist! This massive predator lived approximately 121-112 million years ago during the Early Cretaceous in ...
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Carnotaurus sastrei
Cretaceous
Carnotaurus, meaning "meat-eating bull," was one of the most distinctive predatory dinosaurs ever discovered. Living approximately 70 million years ago during the Late Cretaceous in ...
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Latest Discoveries
August 4, 2026
Charnia
Proterozoic
Charnia is one of the most important fossils ever discovered! This mysterious frond-shaped organism lived during the Ediacaran period, approximately 575 to 555 million years ago, making it one of Earth's oldest known complex life forms. Charnia was the...
Location: England, Canada, Australia, Russia
Scientific Name: Charnia masoni
August 4, 2026
Tribrachidium
Proterozoic
Tribrachidium is one of the strangest creatures to ever exist! Living during the Ediacaran period about 558-555 million years ago, this bizarre disc-shaped organism had three-fold symmetry — a body plan found in no living animal today. It...
Location: Australia, Russia, Ukraine
Scientific Name: Tribrachidium heraldicum
August 4, 2026
Spriggina
Proterozoic
Spriggina is one of the most intriguing fossils from the Ediacaran period, living approximately 550-560 million years ago. With its distinctive horseshoe-shaped head and segmented body, it has sparked decades of debate about whether it represents...
Location: Australia
Scientific Name: Spriggina floundersi
August 4, 2026
Wiwaxia
Cambrian
Wiwaxia is one of the strangest creatures from the Cambrian Explosion, living approximately 508 million years ago. This bizarre armored slug-like animal was covered in overlapping scales and tall defensive spines, making...
Location: Canada (Burgess Shale), China
Scientific Name: Wiwaxia corrugata
August 4, 2026
Pikaia
Cambrian
Pikaia is one of the most important fossils ever discovered—it may be one of our earliest ancestors! This small, leaf-shaped swimmer lived approximately 508 million years ago during the Middle Cambrian period....
Location: Canada (Burgess Shale)
Scientific Name: Pikaia gracilens
August 4, 2026
Olenoides
Cambrian
Olenoides serratus is one of the most famous and scientifically important trilobites ever discovered! Living approximately 508 million years ago during the Middle Cambrian, this trilobite is celebrated for its exceptional...
Location: Canada (Burgess Shale), USA
Scientific Name: Olenoides serratus
August 4, 2026
Ottoia
Cambrian
Ottoia was a fearsome predatory worm that terrorized the Cambrian seafloor approximately 508 million years ago. As the most abundant worm in the famous Burgess Shale, this priapulid (penis worm) used its...
Location: Canada (Burgess Shale), USA (Utah)
Scientific Name: Ottoia prolifica
February 2, 2026
Dickinsonia
Proterozoic
Dickinsonia is one of the most mysterious and ancient creatures ever found! Living during the Ediacaran period about 558-555 million years ago, it was one of Earth's earliest complex life forms. This bizarre oval-shaped organism lived...
Location: Australia, Russia, Ukraine
Scientific Name: Dickinsonia costata
February 2, 2026
Orthoceras
Ordovician
Orthoceras was an ancient straight-shelled nautiloid—an early relative of today's squids and octopuses! Living from the Ordovician to Triassic periods (around 485-200 million years ago), these jet-propelled hunters had long, cone-shaped shells and were among the...
Location: Worldwide (Morocco, Sweden, North America)
Scientific Name: Orthoceras regulare
February 2, 2026
Birkenia
Silurian
Birkenia was a tiny jawless fish that swam in ancient Silurian seas about 430 million years ago! At only 10 cm (4 inches) long, this small but important fish was an anaspid—one of the early vertebrates that...
Location: Scotland, Norway
Scientific Name: Birkenia elegans
February 2, 2026
Tiktaalik
Devonian
Tiktaalik is one of the most important fossils ever discovered—a 375-million-year-old "fishapod" that shows the transition from fish to land animals! Found in the Canadian Arctic in 2004,...
Location: Arctic Canada (Ellesmere Island)
Scientific Name: Tiktaalik roseae
February 2, 2026
Phorusrhacos
Neogene
Phorusrhacos was one of the most terrifying "terror birds"—giant flightless predatory birds that ruled South America for millions of years! Standing 2.5 meters (8 feet) tall with a massive hooked beak, this apex...
Location: South America (Argentina)
Scientific Name: Phorusrhacos longissimus
February 2, 2026
Smilodon
Quaternary
Smilodon, the famous "saber-toothed cat," was one of the most iconic predators of the Ice Age! Living from about 2.5 million to 10,000 years ago, this powerful cat had enormous canine teeth that could...
Location: North and South America
Scientific Name: Smilodon fatalis
February 2, 2026
Woolly Rhinoceros
Quaternary
The Woolly Rhinoceros was a massive, shaggy beast that roamed the frozen steppes of Ice Age Europe and Asia! Living from about 350,000 to 10,000 years ago, this incredible animal was perfectly...
Location: Europe, Asia
Scientific Name: Coelodonta antiquitatis
February 2, 2026
Gorgonops
Permian
Gorgonops was one of the most fearsome predators of the Late Permian period, approximately 260-252 million years ago! Named after the Gorgons of Greek mythology (monsters with snakes for hair), this...
Location: South Africa
Scientific Name: Gorgonops torvus
Did You Know?
dinosaur
Fastest Dinosaurs Hit 70 km/h
Ornithomimus and Gallimimus were the speed champions, reaching up to 70 km/h (43 mph)—faster than a horse! Their ostrich-like build was perfect for running.
dinosaur
Ankylosaurus: The Living Tank
Ankylosaurus had a tail club that could swing with 7,000-8,000 Newtons of force—enough to shatter bones, even a T-Rex's! The club was made of fused bone and could weigh over 20 kg.
evolution
Horseshoe Crabs: 450 Million Years Old
Horseshoe crabs have remained virtually unchanged for 450 million years—they existed before dinosaurs, survived all mass extinctions, and still live today! They're older than trees and sharks.
evolution
Blue Whales: Bigger Than Any Dinosaur
The blue whale is the largest animal EVER—bigger than any dinosaur! At 200 tons, it weighs twice as much as the largest dinosaurs. Some dinosaurs were longer, but none were heavier.
dinosaur
Stegosaurus: Ancient Even to T-Rex
Stegosaurus and T-Rex never met—they lived 80 million years apart! In fact, we are closer in time to T-Rex than T-Rex was to Stegosaurus.
evolution
Tiny Mammals Lived With Dinosaurs
Small mammals existed for over 160 million years alongside dinosaurs! They were mostly nocturnal and mouse-sized, waiting in the shadows until the dinosaurs went extinct.
discovery
The "Dueling Dinosaurs" Fossil
A T-Rex and Triceratops were found fossilized together, possibly killed while fighting! The Triceratops has a T-Rex tooth embedded in its body—evidence of a real prehistoric battle.
dinosaur
Not All Dinosaurs Were Giants
While many famous dinosaurs were enormous, the smallest known dinosaur was the Compsognathus, only about the size of a chicken!
environment
Earth's Oxygen Revolution
About 2.4 billion years ago, the "Great Oxidation Event" dramatically increased Earth's oxygen levels, making complex life possible.
discovery
Soft Tissue in 68-Million-Year Fossils
In 2005, scientist Mary Schweitzer discovered soft tissue, including flexible blood vessels, inside a 68-million-year-old T-Rex bone—a discovery that shocked the scientific world.
evolution
Sharks Are Older Than Trees
Sharks have been swimming in Earth's oceans for about 450 million years—that's 100 million years before the first trees appeared! They survived all five mass extinctions.
environment
One Day Was Only 22 Hours Long
When dinosaurs roamed Earth, days were shorter! The Moon's gravity is slowly slowing Earth's rotation. 200 million years ago, a year had about 385 days.
environment
Dinosaurs Lived Underwater (Almost)
During the Cretaceous, sea levels were 150-200 meters higher than today. About 30% of today's land was underwater, and there was no ice at the poles!
discovery
Dinosaurs Traveled in Herds
Trackway evidence proves many dinosaurs traveled in herds! Parallel footprints in Texas and Colorado show sauropods moving together, and the "Dinosaur Freeway" in Colorado stretches 40 miles.
evolution
Pterosaurs Were Not Dinosaurs
Despite flying alongside dinosaurs for 150 million years, pterosaurs were NOT dinosaurs—they were flying reptiles in a completely separate group. Some had fur-like covering called pycnofibers!
evolution
Crocodiles Outlived the Dinosaurs
Crocodilians have existed for over 200 million years, surviving the asteroid that killed the dinosaurs. They've barely changed because their design is nearly perfect for their lifestyle.
discovery
The Great Dying
The Permian-Triassic extinction event, known as "The Great Dying," wiped out about 95% of marine species and 70% of land species.
environment
Snowball Earth
Around 700 million years ago, Earth was almost completely covered in ice during the "Snowball Earth" period, with temperatures as low as -50°C.
dinosaur
Spinosaurus: A Swimming Dinosaur
Spinosaurus had a paddle-like tail and dense bones for buoyancy—it was semi-aquatic! This 15-meter predator hunted fish in rivers like a giant crocodile-dinosaur hybrid.
discovery
Dinosaurs Lived in Polar Regions
Dinosaur fossils have been found in Alaska and Antarctica! These polar dinosaurs survived months of darkness and near-freezing temperatures, possibly having feathers for warmth.
evolution
Walking Whales
Early whales like Ambulocetus had legs and could walk on land, showing the remarkable transition of mammals back to marine life.
evolution
Largest Flying Animal Ever
Quetzalcoatlus had a wingspan of 10-11 meters—longer than a school bus! This pterosaur was as tall as a giraffe when standing and could fly at 80 mph for days.
dinosaur
Longest Claws Ever: 1 Meter!
Therizinosaurus had the longest claws of any animal ever—up to 1 meter (3.3 feet) long! Despite looking terrifying, this dinosaur was likely a plant-eater that used its claws for grabbing vegetation.