Space 3: Life: The Mesozoic & Cenozoic

🟠 Dinosaurs, mammals, ice ages — to the dawn of humans · 252 million years ago – 10,000 BCE

🟠 Dot 1 · 252 – 201 million BCE

The Triassic: A Coelophysis (SEE-loh-FY-sis), a thin, two-legged dinosaur taller than a person, darts across the hot, dry plains of Pangea.

📍 Address: Space 3 · Dot 1

After the Great Dying, Earth was a quiet place — empty, healing, like a forest floor after a fire. And into that emptiness crept the weeds of the animal world: small, quick, hungry survivors. Among them: the first dinosaurs. And here's the surprise — they were NOBODY. The size of a fox. Long legs, grabbed their food, snatched and ran. The early Triassic rulers were different creatures: fat, lumbering, ugly-beautiful relatives of mammals called therapsids, and crocodile-line hunters with sails on their backs. In the dry riverbeds of what is now Argentina, a little two-legged runner — Eoraptor, 'dawn plunderer' — darted between the giants, eating whatever it could grab. Its hands could GRIP. Its stride could COVER ground. While the big rulers fought each other, the little runners quietly got better at one thing: surviving dry times. And the Triassic had plenty of those — harsh, seasonal, drought-and-rain. Then, 200 million years ago, another catastrophe swept the old rulers away... and the empty stage belonged to the runners. Also hiding in the shadows, barely the size of a shrew: our own ancestors — tiny, nocturnal, darting eyes in the dark. Nobody would have bet on either family. The age of giants was about to belong to the once-nobodies.

🌍 Find it on the globe: Ischigualasto, Argentina and the painted deserts of Arizona, USA

❓ Orient question: After a fire burns a forest down, what comes back first — big trees or little weeds?

🟠 Dot 2 · 201 – 143 million BCE

The Jurassic: A Stegosaurus (STEG-oh-SORE-us), a plant-eater as heavy as an elephant, swings its spiked tail behind the rows of thick plates jutting up from its back.

📍 Address: Space 3 · Dot 2

Now the runners became rulers. By the Jurassic, dinosaurs stopped being fox-sized understudies and became the biggest land animals the Earth has EVER carried. Brachiosaurus: a tower, its head reaching five stories up, cropping the treetops like a giraffe scaled to a building. Its body: dozens of TONS, held up on legs like Greek columns, its heart pumping blood up that long neck. On the ground below, Allosaurus — the Jurassic's big hunter — patrolled with blade-shaped teeth and hooked claws. When the giants passed, the ground itself shuddered. But wait — look up. Something is gliding over the Jurassic lagoon at Solnhofen in what is now Germany: Archaeopteryx, the size of a crow, with feathers. FEATHERS — on a dinosaur! It had teeth, a long bony tail, claws on its wings... and perfect flight feathers, the same design as every bird alive today. This was the secret the dinosaurs had been developing under their skin all along. The age of giants is famous — but the REAL story of the Jurassic was hidden in the understory: dinosaurs were starting to fly.

🌍 Find it on the globe: The Morrison badlands of Wyoming, USA — and Solnhofen, Germany

❓ Orient question: How big is too big? Could a land animal ever be as big as a whale?

🟠 Dot 3 · 143 – 66 million BCE

The Cretaceous: Its snout red with blood, a Tyrannosaurus rex looks up from the carcass of a Triceratops (tri-SARE-uh-tops), noticing a bright new star that’s just appeared in the sky.

📍 Address: Space 3 · Dot 3

The Cretaceous was the dinosaurs' golden age — and they didn't know it was almost over. T. rex, the most famous land hunter ever, ruled Hell Creek: seven tons of muscle, banana-sized teeth, a head built like a wrecking ball. Triceratops, the three-horned tank, held its ground with a shield of solid bone. Flowering plants — brand new! — painted the world's first meadows, and the air was full of NEW smells: the first flowers meant the first bees, the first fruit, the world turning colorful. Sixty-six million years ago, on an ordinary Cretaceous day, a light appeared in the sky. An asteroid, six miles wide, had been traveling toward this moment for millions of years. It hit the Yucatán coast at forty thousand miles an hour. The sky catches fire. The ground liquefies. A wave taller than any mountain crosses the ocean. Dust blacks out the sun — and when the dust settles, the age of dinosaurs is over. No Tyrannosaurus ever saw it coming; nothing that big could hide, and nothing that big could wait it out. But in the smoking dark, small, warm, furry things — our tiny ancestors — were dug into the mud, breathing slow, waiting for morning. This was the day their world began.

🌍 Find it on the globe: Hell Creek, Montana, USA — and the impact crater at Chicxulub, Mexico

❓ Orient question: The dinosaurs had a 165-million-year winning streak. What could end it in a single day?

🟠 Dot 4 · 66 – 23 million BCE

The Paleogene: A Gastornis (gas-TOR-niss), a flightless bird taller than a person, stalks through fern forests with a massive, crushing beak.

📍 Address: Space 3 · Dot 4

After the asteroid, the world was quiet — and the mammals came out of hiding. For 150 million years they had lived small, in the dark, under dinosaurs' feet, growing warm-blooded and quick and clever in the shadows. Now the giants were gone, and the empty Earth belonged to THEM. They grew into EVERY shape of the empty world. Some became wolves, some became whales — and the whales are the wildest story: land mammals walked back into the sea, trading their legs for flippers and their nostrils for a blowhole. In the deserts of Egypt, you can still find the skeletons of whales with TINY legs — walking bones in a swimming body. On land, the forests filled with strange early versions of familiar animals: dawn horses the size of dogs with toes instead of hooves; early elephants with short trunks; lemur-like primates in the branches, with grasping hands and forward-pointing eyes — the eyes that MEASURE and hands that HOLD are the start of something. The Earth was green, warm, and being rebuilt from a blank page. And in one East African branch of that primate family, something odd was happening: the feet were changing.

🌍 Find it on the globe: Wadi Al-Hitan, the whale valley of Egypt's desert

❓ Orient question: The mammals were tiny nobodies for 150 million years. What's the first thing you do when you finally get your chance?

🟠 Dot 5 · 23 – 2.5 million BCE

The Neogene: A Deinotherium (DY-noh-THEER-ee-um), an enormous elephant with downward-curving tusks, lumbers across spreading grasslands.

📍 Address: Space 3 · Dot 5

About 20 million years ago, the world started to dry out. Forests thinned, and a humble new plant conquered the open ground: GRASS. Nothing eats grass like a big animal — no leaves, no fruit, just glass-edged blades. But grass has a secret: it grows from the BOTTOM, not the top. Eat it, burn it, trample it — it comes right back. Grasslands swept across Africa and the world, and with them came herds: zebras' ancestors, antelope, and the first cattle. And in East Africa, the ground itself was tearing apart: the Great Rift Valley was cracking the land open, making cliffs, lakes, and open grassy corridors where dense forest used to be. In the trees along those corridors lived the apes. One family — Australopithecus, in the Afar valley of what is now Ethiopia — did something radical: they came DOWN. On two legs. Standing up let them see over the grass, carry food and babies, and walk for miles in the sun. 'Lucy', the famous skeleton, is one of them: three and a half feet tall, small-brained, but WALKING UPRIGHT. The grasses had opened the world, and a small ape stepped out into it. The next chapter — the whole human story — starts exactly here.

🌍 Find it on the globe: The Afar valley of Ethiopia, East Africa

❓ Orient question: Why do you think the grasses won? They get eaten, burned, and trampled — and still they spread.

🟠 Dot 6 · 2.5 million – 10,000 BCE

The Pleistocene: Humans spread beyond Africa and drop tantalizing clues of what their lives were like. In Australia, the crushed, burned bones of “Mungo Woman” show that people practiced cremation as far back as 40,000 BCE. In France, the elaborate paintings inside Chauvet Cave show that people made gorgeous art as far back as 34,000 BCE. In New Mexico, the fossilized footprints at White Sands show that parents carried their children as far back as 20,000 BCE.

📍 Address: Space 3 · Dot 6

Then came the ice. Over and over, for more than two million years, great ice sheets crawled down from the poles, swallowed the north, held it for a hundred thousand years — and let go, then came AGAIN. The Pleistocene: the age of ice ages. And in the cold, everything grew BIG and WOOLLY. Mammoths with tusks like curly banquets of ivory. Woolly rhinos. Saber-toothed cats with fangs like knives. Giant ground sloths as big as elephants in the Americas. And now, walking into this freezer, comes the strangest animal of all: US. Humans — tall, thin, no claws, no fangs, no fur worth the name — walked out of Africa into the cold. How does a naked tropical ape survive an ice age? Fire. Clothing sewn with bone needles. Words — plans, maps, stories told in advance. And each other. They followed the herds across Beringia, the frozen land bridge between Siberia and Alaska, and spread down two whole continents. By the end of the Pleistocene, humanity had reached from Spain to the tip of South America — the greatest range any land animal ever claimed, carried not by size but by stories. When the ice pulled back for the last time, the mammoths faded away... and the story on the wall walks out of the freezer and into the first villages. That's the next space.

🌍 Find it on the globe: Out of Africa — mammoth steppe from Spain across Beringia to the Americas

❓ Orient question: The weather changed, the sea froze, the giants died — how did the smallest, weakest animal of all survive everything?