translation.en: But remember that this kind of brain, which is much, much smaller — instead of 100 billion neurons, it has 100,000 neurons — but this is the most common form of brain on the planet and has been for 400 million years.
translation.zh: 但请记住到这种大脑 这是小的很多的 没有 1000 个亿神经元，它有 100,000 个神经元 — — 但这是大脑在这个星球上最常见的形式 它存在了4 亿年