Chapter 3: Speciation Surge

After enduring the scorching daytime sun, the night of the seventh day began to descend. The purple Zhao grass still thrived peacefully in the ocean—by now it could withstand five thousand years of alternating sunlight and moonlight. At the same time, as it proliferated massively, the photosynthesis of these aquatic plants caused a dramatic rise in the dissolved oxygen of the seawater, and conditions for the emergence of marine animals were finally in place.

In nature, if there are no aquatic plants and the water cannot circulate, oxygen from the air has little chance to dissolve into it. Such stagnant "dead water" cannot support any marine life. Very soon, spores and single‑celled organisms in the sandbox world's ocean began to evolve. The first to appear were a group of black, crustacean‑like creatures, bearing a striking resemblance to Earth's ancient Paleozoic horseshoe crabs.

Thus, marine animals finally took the stage of evolutionary history.

"My sandbox world… marine animals have at last evolved from single‑celled life. I've waited so long—through two mass extinctions," yate murmured with relief. Exhausted from staying up all day and night, his body could no longer hold up; he returned straight to his room and fell asleep.

When he awoke, it was already the eighth day of his spores‑evolution sandbox creation. Anyone who's studied biology knows the ocean is the cradle of life—but yate discovered that some marine creatures, dissatisfied with the fierce competition underwater, had begun evolving toes and scales, transforming into amphibians living along the barren shore.

He paused to record another page in his neat handwriting, marking the next chapter of the "Light Martial Era." This third epoch of evolution—after the mass extinction—deserved its own name: the "New Life Era."

New Life Era: A new dawn for the epoch, as all manner of creatures burst forth. The first marine animals evolve, ushering in an age of biodiversity; invertebrates, armored by their shells, dominate the seas for a time, only to be overthrown by agile vertebrates. With their advantage, vertebrates rise as the masters of this era, crawling ashore to rule a long stretch of ages!

Having written everything down, yate closed his notebook. On Earth the eras are called Cambrian, Ordovician, Silurian… but in his world they were the "Dark Martial," the "Light Martial," and now the "New Life."

"How fast—it's only been a night, and the spores are about to leave the ocean and evolve terrestrial life…" he thought.

Then a sudden idea crossed his mind: "But how many long epochs must pass before intelligent life emerges? Since the ecosystem is already in place, why not…"

"…stir things up a bit?"

His playful side awoke. He looked at his finger, wondering if he should cut it and drip his blood into the sandbox, hoping some species would absorb human genes and evolve into humanoid intelligences. Could he create mer‑folk naga in the ocean of his yard's sandbox? Or a tribe of mighty ape‑men on the miniature mountains?

But he immediately hesitated—he couldn't bring himself to experiment on actual people. "I remember there's a zoo in the city. I could sneak in some chimp fur, get some gene samples, speed up evolution…" With that thought, he set out.

A few hours later, yate arrived at the zoo. Couples strolled hand in hand, families with children marveled at the exhibits. He stood out as a lone visitor staring intently at the primates.

Nearby, a little family whispered:

"Daddy, look at that man… he's bald but seems so powerful!"

"Don't say that—bald and frail, he looks sick, probably undergoing chemo. A lonely patient at the zoo—how sad."

Yate was only in his early twenties, but chemotherapy's harsh side effects had aged him prematurely; his hair was thinning. He'd been pitiable before, but now he was having the time of his life—evolving species by the dozens.

"Heh," he thought, "Trust me, this bald guy will evolve black, lustrous hair overnight—edit the evolution genes, cure the cancer, and regain my youth."

He didn't actually believe it—it was all too slow—but his sandbox world was already at a Paleozoic stage of ocean and land.

After studying the apes for a while, he picked out a strong male and approached the keeper with a bluff: he was a medical student from a nearby university, tasked by his professor to collect chimpanzee blood for a thesis.

"You're the professor's assistant, brilliant and learned—I believe you," the keeper sighed, touched by yate's thinning hair. "But this chimp is like my own son; I won't let you draw its blood, no matter what."

"One tube of blood," yate offered, placing three thousand yuan on the counter—one month's salary for the keeper. His eyes lit up: "Just one tube? I can draw more!"

"I only need one," yate smiled, stroking his sparse hair in a devilish grin. "Don't worry—I won't tell your boss. And if it works, we can collaborate again—peacock blood, crane blood, I'm interested in all of it."

"Alright, alright!" the keeper rubbed his hands in excitement. "Supporting a student's research is so meaningful."

Moments later, yate left calmly with his prize. With his remaining savings—tens of thousands—he could indulge his hobby for a long time without worry. He was rich, bald, and powerful.

On the way home, he also collected some termites from the roadside—ant genes for strength, and best of all, free. By five in the afternoon he was back in front of his yard, about to enter the sandbox, when someone called out, "Hey, you're yate, right?"

He turned to see a pretty girl on an electric bike.

"I'm Chen Xi—I used to visit your house as a kid. I saw your yard's lights on at night—did you move back?" she asked, surprised.

"It's chemo for stomach cancer—hair loss, fatigue," yate replied.

"You have cancer? But…" Chen Xi stared at him in shock. Then she brightened: "I got into college last year—the same one you went to."

"Congratulations," yate said, nodding.

It dawned on him that she was home for summer vacation. He hurried inside; half a day gone, and he didn't know how the ravenous vermin in his sandbox had evolved. It had been boring to await death, but now life felt unpredictably thrilling.

"They've reproduced insanely—what if they escape? On Earth, they'd be an invasive species," he mused as he stepped over countless tiny creatures, crushing ants and plants underfoot. "This is survival of the fittest. Being stepped on just means you're unlucky—nature's way of weeding you out."

He crouched to examine them one by one. "Time to randomly choose a lucky one for a mass-extinction trial—mix in chimp and ant genes. Survive, and you'll become my sandbox's Paleozoic beast-ape tribe…" He glanced down at his feet, clad in blue plastic shoe covers. "And it'd better be bald."