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
Concavenator corcovatus
Cretaceous
Concavenator, meaning "humpback hunter from Cuenca," was a medium-sized carnivorous dinosaur that lived approximately 125 million years ago during the Early Cretaceous in what is ...
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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 ...
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Tanystropheus
Triassic
Tanystropheus is one of the strangest reptiles ever discovered! Living during the Middle Triassic, approximately 242-235 million years ago, this bizarre creature had a neck that was longer than its body and tail combined! At up to 6 ...
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Latest Discoveries
August 20, 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 20, 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 20, 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 20, 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 20, 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 20, 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
August 20, 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
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
Longest Dinosaur: 42 Meters!
Supersaurus may be the longest dinosaur ever at up to 42 meters (138 feet)—longer than three school buses! Its neck alone was over 15 meters, and its tail stretched 18+ meters.
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.
environment
Prehistoric Super-Sized Insects
During the Carboniferous period, insects grew to enormous sizes due to higher oxygen levels. Dragonflies had wingspans up to 65 cm!
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.
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.
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!
dinosaur
Duck-Billed Dinosaurs: 300+ Teeth
Hadrosaurs had the most complex teeth ever—up to 300 teeth per jaw arranged in "dental batteries." These constantly replaced themselves and could grind the toughest plants.
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!
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.
dinosaur
The Largest Land Animal Ever
Argentinosaurus may have weighed up to 100 tons—as heavy as 14 elephants! Its thigh bone alone was taller than an adult human.
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
SUE: The Most Famous T-Rex
SUE is the largest and most complete T-Rex ever found—90% of the skeleton! The Field Museum paid $8.4 million for SUE in 1997, the most ever paid for a fossil at auction.
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
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.
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.
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.
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!
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.
discovery
Dinosaur Herding Started 193 Million Years Ago
The earliest evidence of herd behavior dates to 193 million years ago! Over 100 Mussaurus eggs and 80 skeletons were found together in Patagonia, showing complex social behavior.
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.
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.
environment
The Crater That Ended the Dinosaurs
The Chicxulub crater in Mexico is 200 km (124 miles) wide—created by an asteroid 10-15 km across traveling at 20 km/second. The impact released energy equal to 4.5 billion atomic bombs!
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.