Science Is About Evidence

But the girl seemed a little shy and reserved, and didn't respond to Xiang Kun. Professor Li explained on her behalf. "She told me before that there's no fixed way to tell, actually. Even birds of the same species can all be different, so you have to judge based on the situation around you at the time. If several birds are calling, you also have to compare their calls against each other. In the end, I suppose you're judging their emotions by their sounds. But I've tried many times based on what she told me, and I still can't hear anything. I figure it has something to do with her better hearing—she can pick out more details and hear a broader range of frequencies..."

They chatted about the topic for a while, and "Little Apple" seemed to grow less shy and joined in the discussion.

Li Yang said his daughter's hearing was better than an ordinary person's, so she could hear more details. That was why it was difficult for him to learn. But this wasn't an issue for Xiang Kun. He was certain his hearing was far, far better than the girl's.

After talking directly with the girl for a while, he also picked up a few tricks for understanding bird calls. Based on the various bird calls he'd heard in the mountains over the past few days, he could confirm that what she said was useful.

But to master it and put it to practical use, he still needed more hands-on practice and training.

As they chatted, Xiang Kun learned that Associate Professor Li Yang was actually from the School of Life Sciences. His main research area was "the interactions among complex microbial communities with important functions in natural and artificial environments." He studied ways to cultivate and isolate previously unculturable microbial groups with significant functions and practical value, by improving cultivation methods and understanding their metabolic traits.

Although Xiang Kun had recently devoured quite a few books on biology, medicine, cells, and genetics, he was still a little lost when Li Yang got into the technical details. All he could do was ask questions like a student.

Xiang Kun had always hoped to consult an expert about his own situation. Professor Li's field and knowledge certainly made him an expert.

Of course, he wasn't about to tell Li Yang directly what was going on with him. Instead, he gradually steered the conversation toward mutations and genetic mutations.

"...Professor Li, do you think birds could mutate for some reason, growing to three or four times their original size, or even five or six times?"

"Do you mean an individual, or an entire population?"

"An individual. Like an owl... or a vulture."

"Almost impossible. You have to understand that growing three or four times bigger could mean gaining more than ten times the body weight. Its bones and muscles wouldn't be able to handle that." Li Yang shook his head. "Even if one appeared, it wouldn't survive. Its entire body structure and tissue strength would have to be rebuilt, but a mutation in an individual wouldn't happen in such an orderly and stable way."

"...Professor Li, do you think it's possible for a person to mutate for some reason? Say, their digestive system changes, altering how they take in energy, and then their other organs and tissues change along with it, improving their physical abilities..."

"You're not asking if a mutation could give someone superpowers, are you?" Li Yang couldn't help laughing. "There's a phrase we often use to describe the characteristics of genetic mutations: widespread, random, infrequent, mostly harmful, rarely beneficial, and undirected."

Li Yang continued to explain. "That means genetic mutations are widespread in the biological world. They can happen at any stage of an organism's development, in any part of its body. They're random, and their frequency is very low. Mutations are generally harmful to an individual, while beneficial ones are very rare. As for being undirected, that means they can produce more than one allele...

"...The human body is a precise, complex, stable, and orderly system. Any change could have terrible consequences. Usually, those consequences show up as illness or deformity. Brother Xiang, you're a programmer. What do you think would happen if a bug appeared in a precisely designed, complex program—something as large as an operating system? Would the bug be good or bad?"

Xiang Kun thought for a moment. "For a programmer or administrator, bugs are definitely bad and need to be fixed. But sometimes, a bug might benefit the user..."

Li Yang nodded. "Exactly. Most of the time, it's harmful. Occasionally, in some special circumstances, it may bring benefits, but there's always a risk of the whole system collapsing. Mutations are the same. If it's a very small mutation, it might have little effect on the human body as a whole, or it might bring some benefit or convenience. For example, a mutation that allows adults to tolerate lactose lets them produce the enzyme that breaks down lactose, so they can enjoy dairy products more freely. But if a mutation has a major impact, any benefits it brings are negligible compared to the harm. It could even set off a domino effect, causing the entire human system to collapse—or even leading to death...

"...In the future, people may be able to modify genes and create superhumans. But right now... the odds of a chance mutation producing a superhero like the ones in movies and comics are practically zero."

In fact, Xiang Kun already knew everything Li Yang had said from all the books on biology and genetics he'd read. It was just that what had happened to him and the Giant Owl made it impossible for him to fully trust the textbooks.

"Professor Li, do you think it's possible that nature has a complete, mature system of mutations that's just been hidden all along... hidden inside certain humans or other organisms, until certain conditions are met and it's activated?"

Li Yang shook his head. "That's already veering into the realm of the supernatural. In works of fiction—novels, movies, and the like—you can just make up whatever rules you want, as long as they're logically consistent. But science is about evidence. Without evidence, you can't just make things up."

Xiang Kun asked again, "Professor Li, what do you think about vampires?"

"If you were asking me about rabies or porphyria, I could discuss those. There are case studies, pathological research, and all kinds of documentation. But vampires, zombies, and the like are essentially the same as superheroes: they're creations of fiction, legends, and myths. There's no actual evidence that they've ever appeared in the real world. So I can only discuss them from a literary perspective, not a scientific one... Hmm, I quite like Interview with the Vampire and Dracula..." Li Yang said with a smile.

Xiang Kun wanted to turn around, grab Li Yang by the collar, and shout at him from the back seat: I'm a vampire! I'm right here, living proof!

But that was only a thought. There was no way he'd reveal his secret to someone he'd just met.

They'd actually reached the foot of the mountain a while ago, but Li Sheng had seen how engrossed the three of them were in conversation—mainly Xiang Kun and Li Yang—and had decided to drive Xiang Kun to the bus station in the city. They were heading back there anyway, so they could keep talking along the way.

When they arrived at the station, Xiang Kun exchanged WeChat contact information with Li Yang, Li Sheng, and Little Apple, then got out and said goodbye.

Watching Xiang Kun walk into the ticket hall, Li Yang shook his head and sighed. "I didn't expect Brother Xiang to be thirty and still so obsessed with superheroes. Oh, Little Apple, what was that word you used before? Something with 'two'?"

"Chuunibyou." Little Apple shook her head as she spoke. "Uncle Xiang isn't being chuunibyou. It seems like he wanted to hear Dad explain the theories behind superheroes and vampires."

"How could that be..." Li Yang said with a laugh.

Li Sheng, who was driving, suddenly said, "Brother Xiang's feet are dirty." After a pause, he added, "Extremely dirty."

"Hm?" Li Yang frowned in confusion. Since they'd hit it off on the way, Li Sheng had given Xiang Kun the pair of slippers he was wearing. Li Sheng couldn't have been complaining about Xiang Kun's dirty feet. He had to mean something else.

Li Yang thought for a moment and understood. "You mean Brother Xiang walked a long way barefoot?"

Li Sheng nodded. "That thick layer of hard mud on his feet definitely didn't come from walking along the mountain road. He must have walked quite a distance through the mountains. And I saw his feet when he washed them. There weren't any cuts on them. That means he knew how to walk in a way that avoided anything that could hurt his feet. I suspect he went into the mountains barefoot on purpose. He didn't wear shoes at all."

"Why would he deliberately go without shoes?" Li Yang asked.

"Maybe he really is an ascetic monk. Tsk, if he'd been wearing a monk's robe, I might've thought he was a kung fu master." Li Sheng laughed at his own joke.

Li Yang shook his head. "Isn't he a programmer? Don't go calling him a monk. He said himself he was bald because of hair loss..."

Just then, Little Apple spoke up beside him. "Uncle Xiang didn't have much of a smell."

The two men were taken aback. It was past two in the afternoon, the sun was blazing, and it was a sweltering day. You didn't even need to walk along a mountain road—just standing still for ten minutes would leave you drenched in sweat.

But now that they thought about it, Xiang Kun had seemed completely dry. They hadn't seen him sweat much at all. Even if the sweat had dried later, there should still have been some sour smell left behind. They both knew that Little Apple's sense of smell was just as sharp as her hearing. If even she said he didn't smell like much, then he probably hadn't sweated much at all.

Li Sheng shook his head with a smile. "There's something interesting about Brother Xiang."