Mei Yiqiu is worried about killing the cat.

Before that, their plan had gone smoothly, even a little too well, so much so that he suspected for a moment that Lester had guessed wrong, there were no aliens at all, otherwise the invaders would have come to their rescue a long time ago.

He imagined that the other party would inevitably use the power of the people who had successfully invaded to exert pressure on the Third Space Foundation through the government or other forces, causing the Foundation to split or even dissolve, and he and several key members had long been prepared for the worst. But in this way, the intruder will inevitably expose some people and strength, and it is better to let them come to the stage than hide in the shadows like shadows.

Of course, the intruder may resort to more extreme measures, such as assassination. Mei Yiqiu had already written her last words in Lester's signature, so that if something happened to her, she would be able to issue another public warning like a human like Lester.

But none of these things happened, but the frequent revelations and cat killings on the Internet were completely unexpected by him, and also disrupted the rhythm of the Third Space Foundation.

In addition to the ongoing space box and dream guide games, their current research focus originally had three directions: one was the development of a gray encephalitis virus vaccine, the second was an in-depth study of the origin of Toxoplasma gondii, and the third was the identification of human consciousness and parasitic consciousness.

Of these three directions, the third is the most difficult, except for the knowledge that alien consciousness can induce the brain to radiate the uncommon radio waves that make Toxoplasma gondii dance a death dance, there are no other discoveries, and there is a high probability that there will be no breakthrough until the space box is successfully developed; The first direction is also difficult due to the small number of virus samples and cases, and the development of a virus vaccine itself is a long process; Only the second one, because of the ubiquity of Toxoplasma gondii, coupled with the fact that there has been a hundred years of research base, seems to have the greatest hope of success.

But once the cat killing order came out, it became difficult to find a cat in the city, let alone observe and experiment in its natural state. Although other animals and humans also have a large number of Toxoplasma gondii, even more than cats, felines are the ultimate reservoir of Toxoplasma gondii, and without cats, one of the most important links is missing.

Mei Ziqing walked into the office wearing white overalls, gloves, and a black and white cat in her arms: "Professor, do you really want to keep it here?" ”

Mei Yiqiu put the pipe in her mouth, reached out and took the cat, put it on her lap and said, "Why not?" There are not many cats on the street now. ”

"But aren't you worried about infection?" Mei Ziqing said worriedly.

Mei Yiqiu laughed and said, "I wasn't worried before, why should I worry now?" Suddenly, his face turned whole, and he said seriously, "The people are panicking because of ignorance, you are a scientist, how can you have such thoughts?" The cat is the definitive host, and Toxoplasma gondii does not run from the definitive host to the human body for no reason. The danger of a cat is that its feces contain a large number of oocysts, as long as they are disposed of in time, you have a cat and you won't lick the cat's butt, how can it be so easy to get infected? ”

"But dogs are different. Dogs like to eat feces and may lick a cat's butt and then come back to lick you, most likely bringing eggs to you. Therefore, the chance of getting infected with toxoplasma gondii in dogs is higher than that of cats. ”

"Of course, the main way humans are infected with Toxoplasma gondii is neither cats nor dogs, but by eating raw meat. There are many intermediate hosts of Toxoplasma gondii, cattle, sheep, chickens, ducks and dogs, and people may be infected if they eat undercooked beef and mutton, poultry eggs or substandard fresh milk. Westerners like to eat fresh food, and we love cooked food since ancient times, which is also the reason why Toxoplasma gondii infection in China is much lower than that in Western countries. In the census in the early 90s, the infection rate of Toxoplasma gondii in China was only 15 percent, and nearly 30 years have passed, and many of the people's living habits have become Westernized, and the situation is not optimistic. As you can see from the sample survey data a while ago, at least in the cities, the infection rate of residents has exceeded 40 percent. ”

Mei Ziqing smiled: "Professor, I know all this. I'm not worried about you! ”

The cat lay on Mei Yiqiu's lap and moved vigilantly and uneasily, with a slight horror in its eyes.

"You see, it's scared." Mei Yiqiu gently stroked the fur on the cat's back, and the cat arched its back and meowed twice, "It can sense that its population is in danger." ”

Mei Ziqing said curiously: "Can it still know about things outside?" ”

"Any species can feel a racial crisis, and of course, it must be at the time of crisis. You don't feel anything wrong with locking yourself in your room, but if you're out there being slaughtered or zombies like in the movies, you're going to feel the danger. If the number of human beings continues to decline, below a certain number, such as 10,000, then you will feel the loneliness of being sparsely populated, even if you don't hear or die. This loneliness is not your personal loneliness, but the loneliness of your race. You must have heard a very famous saying - there are no two identical leaves in the world. ”

"I've heard it, Leibniz's famous saying." Mei Ziqing said.

"But you probably haven't heard another phrase."

"What?"

"There are no two identical leaves in the world, and there is no one and only leaf."

"What does that mean?" Mei Ziqing was puzzled.

Mei Yiqiu laughed: "This is a metaphor made by Professor Frank when describing the quantum state, but later many people in the biology and physics circles extended the interpretation of this sentence, and then deduced a very important theory - the non-uniqueness of the universe. ”

"The non-uniqueness of the universe?" Mei Ziqing said curiously, "Why haven't I heard this theory? ”

Mei Yiqiu said with a smile: "Because this is strictly a philosophical point of view, not a scientific theory. It means that nothing in this universe exists alone, and there must be something of the same kind that exists at the same time. There can't be only one leaf, there can't be only one tree, there can't be only one person, and even the universe isn't unique. Scientifically speaking, it is true that we have not found two identical things, and even in the microscopic world, two identical atoms have different electron trajectories. In the same way, we have not found anything that is the only thing that exists. ”

Mei Ziqing nodded and said: "I understand, this shows that aliens must exist, and there can be no life in the universe only in such a place as the earth." ”

Mei Yiqiu smiled: "You're right, but that's not what I want to talk about. What I want to say is that if all the humans in the world die, and you are the only one left, you will definitely die. Theoretically, you should have died at the same time as the last person besides you died. ”

Mei Ziqing said a little confused: "This is a bit incredible. ”

"You should be able to understand why there is such a thing as a racial crisis by now, right?" Mei Yiqiu picked up the cat on her lap and handed it to Mei Ziqing, "Discuss with Aoki and see if you can find a place to raise more cats." ”

The cat struggled in Mei Ziqing's hand for a while, but Mei Ziqing seemed to understand the little guy's anxiety and restlessness.