What did the world of the dinosaurs look like?

The Age of Dinosaurs ended in fiery disaster

How did dinosaurs become extinct? Explore the Cretaceous extinction event and the role of the Chicxulub impact in the death of dinosaurs (except birds).

What did Earth look like when dinosaurs roamed?

The face of the Earth isn’t remotely the same as when the dinosaurs ruled the roost. The passing of millions of years, plate tectonics, and a spotty track record with asteroid collisions have changed the planet’s surface. Use this interactive globe to see what the Earth looked like millions of years ago.

Explore an interactive timeline and map of dinosaurs across the globe

This tool maps dinosaur habitats based on fossil sites around the world. It includes short articles and additional information—including size, diet, and weight—about each dinosaur. A timeline and data table also allow users to compare dinosaur emergence and extinction dates.

Dinosaurs emerged 245 million years ago when Earth’s continents were still conjoined

Once the supercontinent split apart, dinosaurs evolved into thousands of species as they adapted to their changing environments. All non-avian dinosaurs went extinct about 66 million years ago following an asteroid impact, while avian dinosaurs evolved into today’s birds.

The resulting climate change, not the asteroid impact itself, killed most dinosaurs

Although the Chicxulub impact caused widespread destruction through earthquakes and tsunamis, the subsequent nuclear winter, acid rain, and eventual greenhouse warming drove mass extinction. Roughly 70% of species, including all non-avian dinosaurs, went extinct.

Richard Owen coined the term ‘Dinosauria’ to group three giant reptiles

Identifying similarities in the fossils of Megalosaurus, Iguanodon, and Hylaeosaurus, Owen surmised that they were all part of a broader group of large terrestrial reptile species. The name “Dinosauria” came from combining the Greek words for “fearfully great” (deinos) and “lizard” (sauros).

Dinosaur names have shifted from ancient languages to pop culture references

Early dinosaur names used Greek and Latin roots, often just attaching “-saurus” (lizard) to another word describing a notable trait. Over time, this convention has evolved to incorporate the names of where the discovery was made, local languages, and even celebrities.

There have been five mass extinction events in Earth’s history

Each extinction event has resulted in the loss of at least 70% of Earth’s species at the time of the event, often due to significant changes in global temperatures. The most recent event occurred 66 million years ago and wiped out all non-avian dinosaurs.

There are lots of weird ideas about dinosaur extinction, like hungry, hungry caterpillars

One of the great historical puzzles is this: why did the dinosaurs go extinct? Whether an asteroid, poison plants, volcanos and climate change, or something else, it's still a mystery. Scientists have been debating this question for almost a hundred years. One insect scholar suggests that caterpillars are the culprits.

Civilizations of the past mistook dinosaur fossils for dead mythological creatures

Without knowledge of evolution or extinction, people believed such fossils were the bones of massive animals no one had ever seen alive, including dragons and giants. It was not until the science of paleontology and studies of extinction that these ideas were overturned definitively.

Mammals gradually expanded in size and diversity after the dinosaur extinction

After an asteroid impact caused a mass extinction event 66 million years ago, small mammals were among the few surviving species. With fewer predators, mammals steadily grew larger as new habitats emerged.

About 66 million years ago, an asteroid larger than Mount Everest struck Earth off the coast of the Yucatán Peninsula and wiped out at least 75% of all species, including nearly all dinosaurs.

Dinosaurs’ feathers and greater metabolism helped them survive polar conditions

Studies of dinosaur footprints alongside ice-deposited rock fragments indicate that early dinosaurs adapted to cold weather before the volcanic winters of the Triassic-Jurassic extinction event. These geological events helped dinosaurs to flourish by wiping out their amphibious competitors.

Studies show the asteroid that killed the dinosaurs was from the outer asteroid belt

Isotopic evidence confirms the rock was a carbon-rich asteroid, likely born beyond Jupiter and later knocked into Earth's path after billions of years of orbital drift and gravitational nudges. Its path spanned over 4 billion years and ended in the extinction of 75% of life, including all nonavian dinosaurs.

View a directory of more than 300 dinosaurs

This resource details each dinosaur's taxonomy, type, diet, and habitat, from Aardonyx to Zuniceratops. More well-researched dinosaurs include information on when they were discovered alongside their size, behaviors, and other noteworthy findings.

Air sacs and lightweight bones helped some dinosaurs grow to enormous sizes

After the Triassic extinctions, new species with birdlike anatomy evolved from smaller, early dinosaurs. This anatomy allowed for more efficient breathing and lighter skeletons, favoring the evolution of larger organisms.

Estimates say 2.5 billion total T. rexes lived on Earth

Roughly 68 million years ago, the Tyrannosaurus rex was king of the North American ecosystem. Researchers used the dinosaur's size, metabolic rate, age of sexual maturity, and other factors to determine 20,000 individuals likely were alive at any given time, more than 120,000 20-year generations. This piece breaks down how they arrived at those numbers.

Browse the prehistoric salad bar with these ancient plants

In this video, Benjamin Burger, associate professor of geology at Utah State University's Uintah Basin Campus talks about the different types of plants present during the Mesozoic Era. Professor Burger explores how these plants changed over time, served as food sources for the dinosaurs, and co-evolved with them during this period.

How paleos dig up dinosaurs

Follow Kelsie Abrams and the dig team from the field to the lab, as they unravel mysteries from the end of the age of dinosaurs.

Dinosaurs would likely still roam Earth if the Chicxulub asteroid had hit elsewhere

Some scientists argue that the asteroid's impact would have been less severe if it had struck the ocean instead of shallow seas. In this scenario, small dinosaurs might have become urban survivors, living in cities alongside humans, much like pigeons or rats do today.

Dinosaurs ranged from the size of chickens to multistory buildings, with one of the largest, Argentinosaurus, spanning about 39 meters (128 feet) and weighing more than a Boeing 737.

Dinosaurs are defined by specific traits that many dinosaur-like creatures lack

Although pterodactyls, mosasaurs, crocodilians, and other organisms are mistaken for dinosaurs, they do not have upright legs or specific hip structures characteristic of the terrestrial reptiles. Some, like the Dimetrodon, are more closely related to humans than dinosaurs.

Travel through deep time with this interactive Earth

Explore key moments in Earth’s transformative history as continents drift and climate fluctuates over 4.6 billion years. The Smithsonian presents a series of interactive snapshots of the earth. From its toddler years during the Hadean period, when its surface was mostly molten, to the mostly unidentifiable landmasses of the future earth, 100 million years from now.

Dinosaurs suffered from cancer, arthritis, and infections seen in modern animals

Using CT scans and advanced pathology techniques, paleopathologists have identified respiratory illnesses, malignant osteosarcoma, and other diseases in dinosaurs. The research has helped show how many of these ailments are not exclusively modern phenomena.

Where were the Middle Ages?

Many have equated the Middle Ages to European culture and an era beyond the reach of science and art. This false equivalency minimizes, if not erases, the culture and scholarship that flourished worldwide during this time. Medieval history exists in and across many countries, including China, India, Iran, Sudan, and Ethiopia. In this article, a classical archaeologist details evidence of medieval life around the world.

Bringing dinosaurs back to Mongolia

The Gobi Desert, which crosses Mongolia and China, was a dinosaur hotspot, offering visitors splendid freshwater lakes and a lush, humid climate. These past verdant vast valleys have become the largest dinosaur fossil reservoir in the world, and with that title comes those seeking to remove such items, whether for personal satisfaction or scientific study. This article explains the fight to restore Mongolia's fossil heritage.

Dinosaur portrayals in film mistakenly limit them to only living in tropical climates

The ancient creatures have been brought to life in cinema by combining animatronics and CGI. However, creative liberties have created misconceptions about dinosaurs for audiences, including that the Tyrannosaurus rex could not see stationary prey.

Dinosaurs thrived in the Arctic year round

The Arctic in the Cretaceous Period was a rough place to live, especially in winter. And yet, the fossils of many kinds of dinosaurs have been discovered there. So how were they able to survive in this harsh environment?

Underwater volcanoes significantly contributes to marine extinctions during the Triassic period

An analysis of ocean basins in the Tibetan Plateau helped identify three major periods of volcanism—250-248, 233-231, and 210-208 million years ago—which released significant amounts of greenhouse gases, altering ocean chemistry. The low-oxygen conditions may help explain half of Earth's Triassic extinctions.

The 300-million-year period where Earth looked like a snowball

Life has existed on Earth for at least 3 billion years, but the planet has not always looked like it does today. Rather than the blues and greens of our modern globe, for a 300 million-year period, the Earth was covered in ice and snow, from the poles to the equator. Surprisingly, life was thriving at the time.

Uncovering the evolution of history's largest dinosaurs

This article details how sauropods—the dinosaurs that Little Foot would call longnecks—repeatedly evolved to attain such colossal sizes, towering over other land critters, including tyrannosaurs and mammoths. Sauropods were giant, long-necked...

What is Archaeology?

If you are up-to-date on your Jurassic Park lore, then you likely already know the answer to this question. But for those of us who didn't delve into the world in dinosaurs, it's easy to assume that professionals who study old stuff likely study the remains of what came before us, right? Find out in this article by the Society for American Archaeology.

Six myths about the Middle Ages

The Middle Ages, or medieval era, refers to roughly 500 CE to 1,500 CE. Contemporary opinion perceives this era as "dark" or backward because it was the time between the fall of Rome and the rise of the Renaissance. But much of the era was vibrant, and many myths are just that, including the idea that most people believed the Earth was flat. Watch this video to debunk more myths.

Mammals thrived under the feet of dinosaurs

An explosion of fossil finds reveals that ancient mammals evolved a wide variety of adaptations allowing them to exploit the skies, rivers and underground lairs.

Variations in beak shape helped birds survive the dinosaur extinction event

The asteroid that struck Earth 66 million years ago killed some avian dinosaurs. The smaller species endured by reproducing more quickly and adapting to the environment. Their different beaks allowed them to eat more varied foods for survival.

Georges Cuvier used his knowledge of anatomy to prove extinction had occurred

Extinction had been viewed as impossible because a divine plan for the world would not rationally involve the loss of any of God’s creations. However, mammoth and mastodon bones differed from elephants’, and it seemed impossible that such creatures could be hiding elsewhere on Earth.

Continental drift is supported by matching evidence across disconnected continents

Mesosaurus fossils are found in South America and Africa, but these freshwater creatures could not have travelled across the ocean between continents. Rock layers in the Appalachian Mountains match those seen in Europe, indicating that the mountain belts were once connected.

Explore an interactive timeline of Earth's 4.5-billion-year history to visualize shifting landmasses and oceans, view the locations of significant asteroid impacts, and learn about major geological and biological events.

Watch animations of the creation and excavation of dinosaur tracks

The discovery of a dinosaur trackway in the UK emerged from a controlled explosion that removed limestone from an Oxfordshire quarry. The footprints provide unique insights into dinosaur behavior and movement, with marine fossils suggesting a lagoon-like environment.

Birds are living dinosaurs that evolved from feathered theropods

Traits associated with birds, including feathers, laying eggs, and hollow bones, were first present in dinosaurs and carried through to their descendants. Fossils of these dinosaurs have been found in a sleeping posture, resembling roosting behavior.

Discovering how the dinosaurs went extinct may have helped avert nuclear war

This NPR Throughline episode explains how the 1980 discovery that an asteroid-driven dust cloud killed the dinosaurs inspired Cold War scientists' fears of "nuclear winter"—a sunlight-blocking aftermath of nuclear war that may have discouraged leaders from launching one.

The formation and breakup of Pangaea altered Earth’s geology and biodiversity

Coming from the Greek words for “all” (pan) and “Earth” (gaia), the supercontinent existed from about 320 million to 195 million years ago. The tectonic activity that split Pangaea into today’s continents may one day bring the continents back together, forming Pangaea Proxima.

Unlike the roars in movies, dinosaurs likely cooed, rumbled, and boomed

Fossil evidence and CT scans suggest that many dinosaurs produced low-frequency sounds using resonating crests, closed-mouth vocalizations, or organs similar to those of birds and crocodiles. Larger sounds would not have been helpful for sneakily hunting prey.

Soar above the Jurassic Coast’s 185 million years of geology

This sweeping drone video reveals the stark beauty of the UK’s Jurassic Coast, a 95-mile stretch where Triassic red rock, Jurassic layers, and Cretaceous limestone are exposed—one of the clearest visible records of the Mesozoic era on Earth.

Without dinosaurs, plants could produce fleshy fruits with bigger seeds

Previously disturbed by massive herbivores, denser and darker forests shifted plant evolution, reaching the greatest diversity of seed sizes, fruit sizes, and fruit types about 50 million years ago.

Pterosaurs were dinosaur cousins that ruled the skies

Giant flying lizards or massive leathery birds? Pterosaurs were neither. What they were were the first vertebrates to fly through the skies. This National Geographic video discusses the anatomical features that made their flight possible, how big these awesome creatures could get, and which species was named after a legendary vampire.

The booming fossil industry on the Jurassic Coast

Ever since the Jurassic Coast was registered as a UNESCO World Heritage site in 2001, professional and amateur fossil-finders have increasingly set out for its craggly cliffs to discover ammonites, icthyosaurs, and even new discoveries. This photo essay takes a human look at the growing interest and industry in fossil discoveries along the famed 95-mile strip of England.

The first dinosaur bone ever discovered in Antarctica—a tail bone from a titanosaur—sat in storage for over 40 years before scientists realized what it was.

A timeline of key events during each period of Egyptian history

This timeline shows the dates, periods, dynasties, and significant events in the history and art of ancient Egypt from the Predynastic Period (before 3100 BCE) to the end of the Roman Period (395 CE).

Paleontologists apply rules about rock layering, fossilization, and radioactivity to date geological samples

Concepts such as the understanding that older rock layers will form beneath newer ones allow scientists to compare the ages of samples from various layers. Although no geological site preserves evidence across all time, samples can be combined with fossils of known age, such as those dated by analyzing the decay of their radioactive isotopes, to reconstruct Earth's timeline.