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  • So our brains are built out of neurons and those neurons are fundamentally similar to

  • the very first evolved neurons in jellyfish-like or coral-like animals that first emerged about

  • 600 million years ago. And it turns out that neurons are not that efficient at all. They

  • signal probabilistically, they are unreliable, they leak signals to their neighbors and they're

  • slow. So then the question becomes, well we're really clever, we humans. How do we build

  • clever us out of such crummy parts?

  • And the answer is that, in order to build clever us, we need huge brains. We need an

  • extraordinarily large number of neurons and to have massive interconnection between those

  • neurons. So we have something on the order of 500 billion neurons in the human brain

  • each neuron receiving about 10,000 connections from its neighbors. Now this turns out actually

  • to be really crucial to our humanity because our adult human brain is 1,200 cubic centimeters

  • in volume. That's about three-fold larger than an adult chimpanzee. A newborn human

  • has a brain of volume 400 cubic cm. And it turns out, as women well know that that barely

  • fits through the birth canal as it is. It turns out that death during childbirth is

  • a uniquely human phenomenon. You don't see it in other animals. So you've got a newborn

  • with a 400 cc brain and an adult with a 1,200cc brain. Well, it turns out that if you look

  • at the development of the brain postnatally, there is furious brain development from birth

  • to age five and then much slower brain development from age five to 20, and the brain isn't mature

  • until about the age 20.

  • What does this mean? It means that humans have by far, the longest childhood of any

  • animal. Now, what are the sequelae of that? Well, what it means is that an Orangutan mom

  • can take care of her offspring without any paternal contribution at all, just fine. But

  • it turns out, if you look at humans in hunter/gatherer societies, which is what we were up until

  • the last blink in evolutionary time, single motherhood is not a very viable endeavor.

  • So, single moms aren't very effective in keeping their children alive in hunter/gatherer societies.

  • So that's why we have cross-culturally, marriage or marriage-like institutions. There isn't

  • a single culture that has ever been found that doesn't have something like marriage.

  • The details of the rules can vary, be we all have it. Why do we have this when 90 percent

  • of mammalian species are promiscuous, where both male and female have many sexual partners

  • within a given reproductive cycle where paternity is not well-established and where the male

  • does not contribute in any way in the rearing of offspring? Why are we so aberrant? It's

  • because our neurons are lousy processors, so we need big, fat brains to make clever

  • us. By putting many of these lousy processors together, we can only get 400 cc's worth of

  • these neurons through the birth canal, so we have to have very long post-natal maturation,

  • a long childhood and consequently, that's what creates love. That's what creates our

  • cross-cultural human mating system. It comes from the fact that neurons are lousy processors.

So our brains are built out of neurons and those neurons are fundamentally similar to


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B2 中高級

愛情是糟糕的神經元的產物 (Love is the Product of Lousy Neurons)

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    VoiceTube 發佈於 2021 年 01 月 14 日