過去にスクリプトも音声も作成していた模擬TOEFL iBTのリスニング問題を、Revoicer と ElevenLabs と TTSMP3 で再作成。ただ、リスニング時間が7分超と本番よりかなり長くなってしまった。Official Guide や Longman、North Star などで7分超のリスニング問題も過去にはあったが・・・

まあ、せっかく作り直したのだから、それを世に出すのも悪くない。今回（というか2021年）作ったの discussion は、ホンソメワケベラについて。たしか『 ダーウィンが来た！ 』でも『 サイエンスZERO 』でも両方特集されていたように記憶している。そこから Google Scholar で幸田正典先生を検索、出てきた論文のアブストラクトなどを読み、実際の実験内容や結果を大学のサイトで閲覧、そこから TOEFL っぽい授業を脳内で組み立てて作った。その頃はまだテキスト生成系AIを使っていなかった、というかほぼ知らなかったのですべて自力だった。なので、語数のところでミスったりしたのだろう。

このレクチャーの最後の教授の呼びかけは、実は将棋AIを意識して言わせたもので、生成系AIは当時はまったく念頭になかった。それでも時代が追い付いたというか、非常にタイムリーな内容になったのは、藤井聡太8冠の言葉を借用すれば「僥倖」だった。

Without a further ado, here's a mock TOEFL iBT listening discussion. Enjoy!

Question 01
What is the main topic of the discussion?
(A) The intelligence of mammals
(B) The mirror self-recognition test
(C) Fish cleaning behavior
(D) Artificial intelligence and animal cognition

Question 02

(A) Scientists have conducted the MSR test only on mammals so far.
(B) There are other animals that are capable of passing the MSR test. 
(C) Robert has a clear understanding of the MSR test.
(D) Linda is quite knowledgeable about birds.

Question 03
What does Linda find surprising about the discussion on fish intelligence?
(A) The fact that fish can recognize themselves in a mirror
(B) The types of fish discussed by Professor Stein
(C) The methods used in the mirror test for fish
(D) The contrast between fish and mammal intelligence

Question 04

(A) To correct what has just been said
(B) To describe an experiment procedure
(C) To rephrase a certain term
(D) To emphasize the importance of the experiment

Question 05
What conclusion can be drawn from the results of the fourth experiment with the cleaner wrasses?
(A) Cleaner wrasses cannot recognize themselves in a mirror.
(B) Cleaner wrasses react the same way with or without a mirror.
(C) Cleaner wrasses display self-recognition behavior.
(D) Cleaner wrasses are unable to distinguish between self and non-self.

以下はスクリプトと正答。Have fun!

Listen to part of a discussion in a psychology class.

Professor Stein:
This semester, we have been discussing animal cognition studies. And last week, what did we talk about? Robert? 

Robert:
We talked about some animal species that passed the MSR test, you know, the mirror self-recognition test. Those that passed the test are large animals, like gorillas, chimpanzees, orangutans, elephants, dolphins, and orcas. 

Professor Stein:
So, tell me, Robert. How would you categorize those animals?

Robert: 
Well, I say they are all mammals. 

Professor Stein:
So, do you agree that mammals are the only animal species that can pass the MSR test? 

Robert: 
Umm … I have no idea.

Linda:
Professor Stein, I recently read a scientific journal that said magpies are highly intelligent birds and they’re able to pass the mirror test.

Professor Stein:
Great point, Linda. Magpies sure are known to recognize people’s faces. Studies have shown that they certainly recognize themselves in the mirror. So yes, this bird species did pass the mirror test. However, today I want to draw your attention to something totally different. What we want to discuss in today’s class is … fish intelligence.

Robert:
Fish? You mean like … salmon and mackerel?

Professor Stein:
Yes and no. Yes, fish species. And no. Not those types of fish. All right. So today, I wanna talk about Labroides dimidiatus, aka, the Blue-streak Cleaner Wrasse. This fish, as its name implies, is known for cleaning other fish. They eat exoparasites on the bodies of other fish, which means that they have good eyes for parasites.  Anyways, a Japanese researcher, in collaboration with the Max Planck Society, proved that this fish has the ability to pass the MSR test. Surprising, isn’t it?

Linda:
It is surprising to me. How did they prove that they actually passed the test?

Professor Stein: 
I was just about to do that. OK. So, Linda. Let me ask you. How is a typical mirror test conducted? Quick, tell me.

Linda:
Well, normally, it is done by sticking a mark on a part of an animal’s body, and the animal cannot see that part of the body without the help of a mirror. The animal is anesthetized before the mark is attached, because you want to make sure that it doesn’t know what has been done to it. After the animal regains consciousness, it is exposed to a mirror, so it can see itself. 

Professor Stein:
Precisely! So, if the animal does have the ability of visual self-recognition, what kind of behavior does it typically show?

Linda:
Well, it tries to touch the mark to check to see what it is. 

Professor Stein: 
Yes, yes. Remember, the mark is attached to an area of the body that can be viewed only in a mirror reflection. On the human body, it would be the submental space, you know, the area under the chin, the throat region. 

Robert:
So, are you saying the Japanese researcher did the same thing to cleaner wrasses? Put a mark on the throat region of the fish and see what reactions they showed?

Professor Stein:
Right. They did four types of experiments. Here’s what they did. In experiment number one, they showed this fish a mirror. First, the fish displayed attacking behavior. However, as time passed, it gradually became less aggressive toward the mirror reflection. It then started to swim in an unusual fashion as if to see if the other fish, in the mirror, would do the same thing, and of course it did. Eight healthy subjects underwent this experiment, and all of them displayed the same reaction. At this point, however, there’s no telling if the fish possessed the ability of visual self-recognition.

Professor Stein: 
Experiment number two. This time, they put a transparent mark on the throat region of the fish. Keep in mind that this mark is absolutely harmless and totally unperceivable. What do you think happened? Linda?

Linda: 
It tried to remove the mark, didn't it?

Professor Stein: 
Sorry. That was a bit of a tricky question. In this experiment, experiment number two, the fish was not given access to a mirror. 

Linda:
I see. So it couldn’t see itself in a mirror. So, what did it do? I guess it did nothing.

Professor Stein: 
You’re right. It didn’t do anything peculiar. Natural, isn’t it? Because it never knew there was a mark on its throat. Also this time, they used eight different individual fish, and the results were the same. OK, experiment number three. This time, they put a brown, visible mark on the throat region of the fish, but no access to a mirror. Robert, what do you think happened?

Robert: 
Lemme see … Since there was no mirror, the fish couldn’t have known there was a mark on its body. So, the same as the result from experiment number two. I say it did nothing.

Professor Stein: 
Correct. Again, this experiment was done eight times using eight different individual fish. The same results. So, the fourth and final experiment. In this last experiment, what did they do? Well, they put a brown mark on the throat region of the fish and gave the fish access to a mirror. What did the researchers observe? Predictably, the fish behaved differently. This time, they looked at themselves, and realized something was wrong with them. Then, they swam down and scraped their bodies, specifically, the throat region, against the pebbles on the bottom of the water tank over and over. Then, they swam up to look in the mirror. What do you think this indicated? 

Linda: 
Well, the fish noticed the mark. Therefore, they attempted to get rid of it. 

Professor Stein:
Yes and yes. Seven out of eight subjects showed this scraping behavior. From this, you could say that cleaner wrasses are in fact able to recognize themselves. The Japanese researcher and his team believe that the fish regarded the marks as parasites, which, therefore, caused them to try to remove them. This behavior couldn’t have been triggered if it hadn’t been for the ability to distinguish self and non-self.  It is very likely that this fish species has self-recognition capabilities.

Robert: 
Professor, I got a question. Did they do another experiment? I mean, what would happen if the fish had a visible mark on a part of the body that they can see without a mirror?

Professor Stein:
Great question. You have all the makings of a scientist. Of course, they did the test you just mentioned, in addition to the four tests that they originally came up with. The result was, they tried to scrape off the mark. No surprise there, right? 

Professor Stein:
We used to think that fish were among the least intelligent animals by vertebrate standards. However, the more we find out about animals, the more obscure the border between humans and animals becomes. In this day and age, artificial intelligence is gaining considerable attention across society. But those of you who haven’t decided on your major yet. I wanna say to you that there is so much more to explore about animal intelligence.

正答
Q1  (B)
Q2  (B)
Q3  (A)
Q4  (C)
Q5  (C)