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
Tyrannosaurus Rex
Cretaceous
Tyrannosaurus rex, commonly abbreviated as T. rex, is one of the most iconic and extensively studied dinosaurs. It lived approximately 68–66 million years ago during the Late Cretaceous period, inhabiting what ...
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Eurypterus remipes
Silurian
Eurypterus remipes is the most famous of the "sea scorpions" and the official state fossil of New York! This remarkable arthropod lived approximately 410 million years ago during the Silurian period, swimming through the ...
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Oxalaia quilombensis
Cretaceous
Oxalaia was a massive spinosaurid dinosaur that lived approximately 100-94 million years ago during the Late Cretaceous in what is now northeastern Brazil. This giant predator ...
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Latest Discoveries
October 22, 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
October 22, 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
October 22, 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
October 22, 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
October 22, 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
October 22, 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
October 22, 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
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?
evolution
Saber-Toothed Cats Ruled Americas
Smilodon, the famous saber-toothed cat, had 28 cm (11-inch) fangs and lived throughout North and South America. Over 1,200 specimens have been found in the La Brea Tar Pits alone!
discovery
Amber: 230-Million-Year Time Capsules
The oldest creatures preserved in amber are 230 million years old! These tiny mites from Italy are 100 million years older than any other amber fossils, perfectly frozen in tree resin.
discovery
Dinosaurs Didn't Roar Like in Movies
Scientists believe dinosaurs made closed-mouth sounds like cooing, booming, or growling—similar to crocodiles and ostriches today—not the dramatic roars from Jurassic Park!
dinosaur
Dinosaur Eggs Were Surprisingly Small
Even the largest dinosaurs laid relatively small eggs—about the size of a football. If eggs were bigger, the shells would be too thick for babies to break out!
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 Fish That Came Back From Extinction
The coelacanth was thought extinct for 65 million years—until one was caught in 1938! Called a "living fossil," it has barely changed in 400 million years and was like finding a living dinosaur.
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
First Land Animals
Tiktaalik, living 375 million years ago, was one of the first vertebrates to venture onto land, with primitive lungs and leg-like fins.
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
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.
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 May Have Been Colorful
By studying fossilized melanosomes (pigment cells), scientists discovered some dinosaurs had bright colors! Sinosauropteryx had a striped tail like a raccoon.
evolution
Megalodon: 7-Inch Teeth Monster
Megalodon's teeth could reach 7.5 inches (19 cm)—three times larger than great white shark teeth! This 20+ meter shark had the strongest bite of any animal ever: 182,000 Newtons.
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.
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!
environment
Hangenberg event
The Hangenberg event, about 359 million years ago, was a mass extinction at the Devonian-Carboniferous boundary, caused by global cooling and anoxic oceans, wiping out many marine species.
environment
Ordovician-Silurian extinction
The Ordovician-Silurian extinction, around 445 million years ago, was caused by a rapid ice age and fluctuating sea levels, eliminating nearly 85% of marine species.
dinosaur
T-Rex vs Triceratops: Real Rivals
T-Rex and Triceratops actually lived at the same time and place! The Hell Creek Formation contains both—Triceratops makes up 40% of fossils there, T-Rex 24%. They definitely encountered each other.
discovery
First Dinosaur Named: 1824
Megalosaurus was the first dinosaur ever scientifically named, by William Buckland in 1824. The word "dinosaur" itself wasn't invented until 1842 by Richard Owen!
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.
discovery
Dinosaur Footprints Everywhere
Thousands of dinosaur trackways have been found on every continent! Some tracks in Colorado show dinosaurs walking together in herds, and some footprints are over a meter wide.
evolution
Birds Are Living Dinosaurs
Modern birds are actually living theropod dinosaurs, having evolved from a group of dinosaurs called maniraptors.
dinosaur
T-Rex Teens Gained 45 lbs Per Week
During their teenage growth spurt, T-Rex gained 35-45 pounds PER WEEK until reaching adult size around age 20! Growth rings in SUE's bones revealed this incredible growth rate.