A Beijing socialite stole my boyfriend; she went crazy after I got married.

Xie Yuan keenly sensed a subtle similarity between dinosaurs and birds and began to think about the basis for classification and logical relationships.

Jiang Chu bent down and picked up her daughter. "Does Xiaoyuan like birds?"

Xie Yuan tilted his head, neither saying he liked it nor disliked it.

It seems this isn't targeting birds.

Jiang Chu thought about it with great interest.

Dinosaurs and birds are just one node in her vast network of observations.

What fascinates this child is not a specific thing, but the connections, patterns, and logical relationships between things.

"...You asked a very insightful question."

Jiang Chu lifted her daughter in her arms.

Xie Yuan blinked his big eyes at her. "Impressive?"

“That’s right,” Xie Jing stood up, “the focus of the most intense debate in modern evolutionary biology in the last thirty years…”

He reached out and hugged his wife and daughter, asking, "Where exactly is the boundary between basal birds and early birds?"

Xie Yuan's mosquito coil eyes.

Jiang Chu: "...This is not a university lecture hall, Professor Xie."

As she spoke, she secretly patted her husband and pinched him twice.

Xie Jing silently grabbed his wife's mischievous little hand, casting a helpless glance that carried a hint of warning.

"In short," Jiang Chu coughed lightly, "just remember this: many, many years ago, before DNA technology existed, the pioneers of biological taxonomy could only rely on the naked eye to judge appearances. So they thought that creatures with hair and the ability to fly formed their own class called birds, and creatures that were bald and covered in scales were called reptiles. But as more fossils were unearthed and anatomy developed..."

Xie Jing: "What you said is so clear and concise, even a preschooler would understand it instantly, Professor Jiang."

Jiang Chu: "..."

Jiang Chu: "I told them to remember this first! Remember it! As for why, they'll understand when they're a few years older!"

Xie Jing bent down and picked up Xie Zhuo, who was tilting his head and listening intently. "Did you remember?"

The little guy blinked. "DNA?"

Xie Yuan listened intently, his delicate eyebrows furrowed, his little head working at a rapid pace.

What is "outline"?

Xie Jing took out the third brother's multi-layered nested building block box from the storage basket next to him.

He placed the largest red box at the bottom, and then nested the boxes inside one by one.

"Look, biological classification has big boxes and small boxes. This is the biggest box, the kingdom. We are animals, and that is a plant."

He casually pointed to the potted plants in the distance, "Next is the phylum Chordata, we are the phylum Chordata."

Jiang Chu reached out and pressed her daughter's soft back. "This is the spine, a long, hard bone. Can you feel it?"

Xie Yuan awkwardly reached back to touch his back, then his eyes lit up and he nodded vigorously.

"Great." Xie Jing took out another yellow box and gently placed it inside. "Next, it's about the 'class' that Xiao Yuan asked about earlier. Humans belong to the 'mammals' class."

"Why are we called Mammalia?" Jiang Chu picked up the conversation, her eyes crinkling as she gently rubbed her daughter's tummy. "Because when Xiao Yuan, your brother, and your younger brother were first born, they all drank their mother's milk. You all have soft fur on your bodies, and we're always warm, unlike little lizards that have to lie on rocks to bask in the sun for warmth. These are all hallmarks of the Mammalia family."

Xie Zhuo moved over as well, reaching out his warm little hand to touch his sister's cheek, then touching his own face. "It's warm."

Xie Jing then placed the box down, "Primate eyes—"

Jiang Chu grasped her daughter's hand. "Look, our fingers and toes can bend like this, our hands can grasp, and our thumbs are separated from the other fingers like this..."

She spoke about the parts that the children could understand most: "We are members of the Hominidae family, Homo genus, Homo sapiens species, all humans, you, your parents, and all the uncles and aunts you have met are human beings."

Xie Yuan looked at the seven boxes in front of his father. They were neatly nested together, tight and easy to understand.

The little girl also fell into deep thought, "Where are the birds' and the little raptor's houses?"

Xie Jing picked up the model and pointed to the yellow box:

"The class of birds is called the Aves. They are covered in feathers specifically for flight, and their bones are hollow, like small straws. They have no teeth, only a hard beak. They don't drink their mother's milk; instead, they hatch from an egg laid by their mother."

Jiang Chu then picked up the small raptor with its metallic blue sheen and placed it next to the bird for comparison:

"Our Microraptor, in traditional classification, belongs to the dinosaur family of the Sauromorpha. You see, although it also has beautiful feathers, it has a row of small, sharp teeth in its mouth, a long, solid tail, and sharp claws like small hooks on its feet, making it look more like a small dinosaur wearing a feathered coat."

"But—" Xie Jing added in a low voice, "The history of biological evolution is very long, just like this block box. Sometimes the amazing life forms created by nature are so abundant that the boxes that humans make with rigid frames may not be able to contain them all. So, this is just a way of classifying things to help you understand the world; it is not an absolute answer."

This grand and intricate evolutionary logic is extremely informative for the young.

Xie Yuan held the little bird in his hands, looked at the Microraptor, and then pushed the yellow box with his chubby little hand. "The little bird and the Microraptor are neighbors!"

Jiang Chu hugged her and kissed her. "That's fine too."

Xie Zhuo tilted his head. "What about Big Dragon?"

He uttered a few indistinct words, but Xie Jing could still tell that his son was talking about Triceratops and Brachiosaurus.

Xie Jing picked out two more building blocks of different shapes from the storage basket and then picked up his eldest son.

"Look, in the big box of dinosaurs, people use the shape of their pelvises—that is, the bones on their buttocks—to separate them."

Jiang Chu smiled and gently pinched Xie Zhuo's little bottom, making the little guy shrink back and giggle.

"The first corridor is called Saurischia."

Xie Jing pointed to Microraptor, "Their pelvis was shaped like a small lizard's, and they were all close-knit carnivorous theropod dinosaurs. The branch that evolved into all the small birds we have today came from this corridor."

Jiang Chu took the opportunity to pick up a picture book and handed it over.

Xie Jing opened the picture book and explained it page by page, while Xie Zhuo listened attentively beside him.

Xie Yuan had already fallen asleep in his mother's arms.

The little girl overused her brain today, spending most of the day navigating the complex maze of biological classifications, and she's clearly tired now.

Her long eyelashes drooped, her small mouth was slightly pouting, and she was still loosely clutching the colorful peacock and pheasant model in her hand, her breathing long and even.

Jiang Chu gently and carefully picked up her daughter.

The two-year-old was as soft as a warm marshmallow, and naturally snuggled his little head into his mother's neck, letting out a very soft hum.

Jiang Chu went straight upstairs.

She gently placed her daughter on the cloud-shaped bed covered with light pink pure cotton bedding, tucked her in, and placed the little peacock and pheasant model in the distance.

Then he bent down and placed a goodnight kiss on the girl's forehead before quietly closing the door and leaving.

Just as I turned the corner in the corridor, I heard muffled thumping sounds coming from the room next door.

Jiang Chu entered the third brother's room.