from: newyorker.com

http://www.newyorker.com/science/maria-konnikova/why-are-babies-so-dumb-if-humans-are-so-smart

(1)

As a species, humans are incredibly smart. We tell stories, create magnificent art and astounding technology, build cities, and explore space. We haven’t been around nearly as long as many other species, but in many respects we’ve accomplished more than any have before us. We eat them and they don’t eat us. We even run scientific studies on them—and are thinking about re-creating some of those that have gone extinct. But our intelligence comes with a curious caveat: our babies are among the dumbest—or, rather, the most helpless—that exist. A baby giraffe can stand within an hour of birth, and can even potentially flee predators on its first day of life. A monkey can grasp its mother and hang on for protection and nourishment. A human infant can’t even hold up its own head.

incredibly adv. 难以置信地

magnificent adj. 华丽的

astounding adj. 惊人的

accomplish vt. 完成

extinct adj. 灭绝的

curious adj. 好奇的

caveat n. 警告

dumb adj. 愚蠢的

giraffe n. 长颈鹿

flee vt. 逃跑

predator n. 捕食者

nourishment n. 营养

infant n. 婴儿

作为一个物种，人类非常聪明。 我们讲故事，创造壮丽的艺术和惊人的技术，建造城市，探索空间。 我们并没有像其他许多物种一样长，但在很多方面我们已经完成了比以前更多的任务。 我们吃他们，他们不吃我们。 我们甚至对它们进行科学研究 - 并且正在考虑重新创造一些已经灭绝的那些。 但是我们的智慧带来了一个奇怪的警告：我们的婴儿是存在的最愚蠢的，或者说是最无助的。 小长颈鹿可以在一个小时内出生，甚至可能在其生命的第一天逃离掠食者。 一只猴子可以抓住它的母亲并继续保护和营养。 一个人类的婴儿甚至无法举起自己的头。

(2)

The evolution of human intelligence isn’t something that Celeste Kidd had ever pondered. A developmental cognitive scientist who currently works at the University of Rochester, her work had focussed mostly on learning and decision-making in children. Over years of observing young children, she became impressed with the average child’s level of sophistication. But when she looked at the infants she encountered, she saw a baffling degree of helplessness: How could they be so incompetent one second and so bright so soon thereafter? One day, she posed the question to her colleague Steven Piantadosi. “Both of us wondered what could possibly justify the degree of helplessness human infants exhibit,” she told me recently. “Even other primate babies, like baby chimps, which are close in evolutionary terms, can cling onto their moms.” She began to see a contradiction: humans are born quite helpless, far more so than any other primate, but, fairly early on, we start becoming quite smart, again far more so than any other primate. What if this weren’t a contradiction so much as a causal pathway?

pondervt. 思考，沉思

cognitiveadj. 认知的

sophisticationn. 复杂，世故

encounter vt. 遭遇

baffling adj. 莫名其妙的

degree n. 程度, 度

incompetent adj. 无能的

justify vt. 替...辩护

primate n. 灵长类动物

chimp n. 黑猩猩

contradiction n. 矛盾

causal n. 因果

pathway n. 途径

人类智慧的发展并不是Celeste Kidd曾经思考过的。作为目前在罗切斯特大学工作的发展型认知科学家，她的工作主要侧重于儿童的学习和决策。多年来观察幼儿时，她对普通孩子的成熟程度印象深刻。但是当她看到她遇到的婴儿时，她看到了一种莫名其妙的无助感：他们怎么可能一秒钟如此无能，而且很快就会如此光明？有一天，她向她的同事史蒂芬Piantadosi提出了这个问题。 “我们两个都想知道什么可能证明人类婴儿无助的程度，”她最近对我说。 “甚至其他灵长类婴儿，如进化上接近的婴儿黑猩猩，都可以紧贴在他们的母亲身上。”她开始发现一个矛盾：人类生来无助，远比其他任何灵长类动物都强，但是在相当早的时候，我们开始变得相当聪明，再比其他任何灵长类动物都要多。如果这不像一个因果途径那么矛盾呢？

(3)

That’s the argument that Kidd and Piantadosi make in their new paper, published in a June issue of PNAS. Humans become so intelligent because human infants are so incredibly helpless, they argue; the one necessitates the other. The theory is startling, but it isn’t entirely new. Researchers have been pondering the peculiarities of our birth and its evolutionary significance for quite some time. Humans belong to the subset of mammals, called viviparous mammals, that give live birth to their young. This means that infants must grow to a mature enough state inside the body to be born, but they can’t be so big that they are unable to come out. This leads to a trade-off: the more intelligent an animal is, the larger its head generally is, but the birth canal imposes an upper limit on just how large that head can be before it gets stuck. The brain, therefore, must keep maturing, and the head must continue growing, long after birth. The more intelligent an animal will eventually be, the more relatively immature its brain is at birth.

startling adj. 触目惊心的

peculiarity n. 特点

evolutionary adj. 发展的，进化的

significance n. 重要性，意义

mammal n. 哺乳动物

viviparous mammals n. 胎生哺乳动物

mature adj. 成熟的

immature adj. 未成熟的

trade-off n. 交易，权衡

birth canal 产道

impose vt. 强加

stuck vi. 卡住

这就是基德和Piantadosi在6月份出版的PNAS上发表的新论文中提出的论点。他们认为，人类变得如此聪明，因为人类的婴儿非常无助，一个需要另一个。这个理论是令人吃惊的，但它并不是全新的。研究人员一直在思考我们出生的特点及其进化意义。人类属于哺乳动物的一部分，称为胎生哺乳动物，它们能够活到出生。这意味着婴儿必须在身体内成长到足够成熟的状态才能出生，但它们不能太大以至于无法出来。这导致了一种权衡：动物越聪明，它的头部通常就越大，但产道对头部卡住前的大小有多大限制。因此，大脑必须保持成熟，并且头部必须在出生后很长时间继续生长。动物最终会变得越聪明，它的大脑在出生时就越不成熟。

(4)

Researchers have long known about this trade-off, and about the connection between brain size and neural density and intelligence. For instance, Robin Dunbar found that the ratio of neocortical volume to brain size can predict the social-group size in a number of species, including bats, cetaceans, and primates, while Simon Reader has demonstrated links in tool use and innovation to brain size in primates. Kidd and Piantadosi’s new idea is that increased helplessness in newborns mandates increased intelligence in parents—and that a runaway selection dynamic can account for both.Natural selection favors humans with large brains, because those humans tend to be smarter. This may create evolutionary incentives for babies that are born at an even earlier developmental stage, which require more intelligence to raise. This creates the dynamic: over time, helpless babies make parents more intelligent, which makes babies more helpless, which makes their parents more intelligent, and so on.

neural density 神经密度

neocortical n. 新皮层

cetacean n. 鲸类

innovation n. 革新

incentive n. 激励

研究人员早就知道这种折衷，以及大脑与神经密度和智力之间的联系。 例如，Robin Dunbar发现新皮层体积与脑部大小的比率可以预测包括蝙蝠，鲸类动物和灵长类动物在内的许多物种的社会群体大小，而Simon Reader已经证明了工具使用和创新与大脑大小的联系 在灵长类动物。 Kidd和Piantadosi的新想法是，新生儿无助感的增加要求增加父母的智力 - 而失控的选择动力可以解释这两种情况。自然选择倾向于拥有大脑的人，因为这些人往往更聪明。 这可能会为婴儿出生在更早的发育阶段，这需要更多的智力提高，从而产生演化激励。 这创造了动态：随着时间的推移，无助的婴儿让父母变得更聪明，这使得婴儿更加无助，这使得他们的父母更加聪明，等等。

(5)

During their investigation, Kidd and Piantadosi realized something important that strengthened their theory. It turns out that another variable has an even higher correlation with intelligence than brain size—time to maturity, or weaning time. In other words, the time it takes to shepherd newborns through absolute helplessness to a point of relative self-sufficiency predicts primate intelligence more strongly than the best measure that has previously been proposed, namely, head circumference. Orangutans have smarter babies than baboons and they wean them longer. Baboon babies, in turn, are weaned longer, and are smarter, than lemur babies.

investigationn. 调查

variablen. 变量

correlationn. 相关

weaning断奶

self-sufficiency自给自足

predictvt. 预测

circumferencen. 周长

Orangutans猩猩

baboons狒狒

在他们的调查过程中，基德和Piantadosi意识到一些重要的东西加强了他们的理论。 事实证明，另一个变量与智力的关联性要比脑的大小 - 成熟时间或断奶时间更高。 换句话说，把新生儿通过绝对无助的方式培育成相对自足的时间比预先提出的最佳措施（即头围）更能强烈地预测灵长类动物的智力。 猩猩比婴儿有更聪明的宝宝，他们会更长时间地消除它们。 反过来，狒狒婴儿比狐猴婴儿断奶时间更长，而且更聪明。

(6)

Putting these facts together helped Kidd and Piantadosi develop their hypothesis. The connection between head size and intelligence does create incentives for babies to arrive earlier. But it’s the connection between weaning time and intelligence that may really be driving the cycle. You need to be smarter to care for more helpless creatures, which means you need a larger brain—which means that babies have to enter the world at an even more helpless stage of development, since there is a finite size to their brain at birth, mandated by the physiology of live birth. And so the cycle continues.

hypothesis n. 假设

creature n. 生物

mandate vt. 要求

综合这些事实，帮助基德和皮坦多斯发展了他们的假设。 头部尺寸和智力之间的联系确实为婴儿提前到达提供了动力。 但是断奶时间和智力之间的联系可能真正推动了这个循环。 你需要更聪明地去关心更无助的生物，这意味着你需要更大的大脑 - 这意味着婴儿必须在更加无助的发展阶段进入这个世界，因为出生时他们的大脑的大小是有限的， 活产的生理学授权。 这个循环继续下去。

(7)

Of course, the theory is just that—a model. Ideally, to prove it you would look at head size, birth time, and intelligence over the span of human evolution, to see if we were born earlier as we got smarter—data that are unavailable. (Kidd also stresses repeatedly that this theory supplements, but does not supplant, earlier ones: it can coexist quite naturally with both the social-group account of intelligence—the Dunbar approach—and what’s called the metabolic accounts of intelligence, which posits that our digestive system has allowed for our brain’s high metabolic needs, and that we grew smarter to be able to find and share difficult-to-gather food.) But there are some intriguing converging pieces of evidence. For one, other animals that are not viviparous have not evolved the same levels of intelligence, suggesting an inherent link between live birth and brainpower. And in modern humans, a few pieces of evidence appear to suggest that smarter parents are more likely to have offspring that survive. In one limited sample—two hundred and twenty-two Serbian Roma women—maternal I.Q. and child mortality were negatively correlated (that is, higher I.Q. meant lower mortality), even controlling for education, age, and a number of other factors. In a larger sample of Californian parents, in 1978, years of education were linked to infant-mortality rates. Global epidemiological studies suggest a decrease in mortality that equals between seven and nine per cent for each year of a mother’s education. None of this is decisive, of course, but it is suggestive.

ideally adv. 理想地情况下

supplement n. 补充

supplant vi. 取代

coexist vi. 共存

metabolic adj. 新陈代谢的 变化的

digestive system 消化系统

intriguing adj. 奇妙的

viviparous adj. 胎生的

inherent adj. 固有的

offspring n. 后代

mortality n. 死亡 死亡数目

epidemiological n. 流行病学

decisive adj. 决定性的

当然，这个理论就是这样一个模型。理想情况下，为了证明这一点，您需要查看人类进化过程中的头部尺寸，出生时间和智力，以查看我们是否因为我们得到更智能的数据而更早出生 - 无法获得数据。 （基德也一再强调，这个理论补充了，但并没有取代早期的理论：它可以非常自然地与社会群体的智力 - 邓巴方法 - 以及所谓的智力的代谢账户共存 - 这就是说，我们的消化系统已经允许我们大脑的高代谢需求，并且我们越来越聪明，能够找到并分享难以收集的食物。）但是有一些有趣的收敛性证据。首先，其他没有胎生的动物也没有进化出相同水平的智力，这表明活产与脑力之间存在内在联系。而在现代人类中，有少数证据表明聪明的父母更有可能生育下一代。在一个有限的样本中 - 220名塞尔维亚罗姆妇女 - 母亲I.Q.和儿童死亡率呈负相关（即IQ越高意味着死亡率越低），甚至控制了教育程度，年龄和许多其他因素。在1978年，一个更大的加利福尼亚州父母样本中，多年的教育与婴儿死亡率有关。全球流行病学研究表明，母亲教育每年的死亡率下降7％至9％。当然，这些都不是决定性的，但这是暗示性的。

(8)

There is, of course, one follow-up question: Why did this cycle happen to humans and not to lemurs? When I asked Kidd about this, she told me that their theory cannot offer an answer—likely as not, it’s a matter of pure genetic luck that became self-reinforcing. As we grew smarter, we were better able to take care of our infants, so they could be born more helpless and allow us to grow even smarter.

lemur n. 狐猴

当然有一个后续问题：为什么这个循环发生在人类而不是狐猴身上？ 当我向基德询问这件事时，她告诉我他们的理论不能提供答案 - 可能并非如此，纯粹的遗传运气成为自我强化的问题。 随着我们变得越来越聪明，我们能够更好地照顾我们的婴儿，所以他们可能会变得更加无助，并让我们变得更聪明。

(9)

One intriguing way to test the hypothesis further: look at twins. Typically, twins are not carried to full term. Does that mean that twins are more intelligent than non-twins, since they require longer weaning time—and would a mother who is a twin, in turn, give birth to smarter children? “It’s a really good question, to look at the types of twins that run in families and whether that leads to higher intelligence,” Kidd said. “It’s a predictable hypothesis,” and one that they may well include in their ongoing research on train heritability in twins. And it’s a hypothesis that came, of all places, from a five-year-old—Kidd was being interviewed about twins for a podcast by the daughter of Sindya Bhanoo, a former columnist at the Times. Dumb babies, maybe, but oh so smart, oh so soon thereafter.

Typically adv. 通常，代表性地

predictable adj. 可预测的

heritability n. 遗传

columnist n. 专栏作家

进一步验证假设的一个有趣的方法是：看双胞胎。 通常情况下，双胞胎不会完成任期。 这是否意味着双胞胎比非双胞胎更聪明，因为它们需要更长的断奶时间 - 而且双胞胎的母亲反过来会生出更聪明的孩子？ “这是一个非常好的问题，看看在家庭中出现的双胞胎类型，以及是否会导致更高的智力，”基德说。 “这是一个可预测的假设，”他们可能会把他们列入正在进行的双胞胎训练遗传研究中。 这是一个来自五岁小孩的所有地方的假设--Kidd正在接受一位前泰晤士报专栏作家Sindya Bhanoo的女儿的双胞胎访谈。 哑巴宝宝，也许吧，但是哦，这么快就会很快哦。

单词

magnificent：华丽的；宏伟的

astounding：令人惊讶的; 令人震惊的

caveat：警告; 提醒

flee：逃离，逃走

predator：食肉动物，捕食者

ourishment：营养（的供给）

evolution：进化，演变

impress：使留下印象，使铭记在心

sophistication：复杂性; 先进

baffling：令人困惑的

infant：婴儿；幼儿

startling：惊人的

peculiarit：特性；怪癖

mammal：哺乳动物

viviparous：(动物)胎生的

wean：使断奶

maturity：发育成熟

circumference：周长

orangutan：猩猩

lemur：狐猴

baboon：狒狒

hypothesis：假设

mandate：强制执行，授权

span：时间段，持续时间

metabolic：新陈代谢的

intriguing：新奇的

converging：聚集，会合

offspring：子女，后代

mortality：死亡人数

carry：怀(胎)

ongoing：进行中的; 继续存在的

thereafter：其后

重点词汇

not nearly：远没有

incompetent：无能的， 不称职的

pose：提出（问题），造成，摆姿势

argument：论据

variable：多变的，可变因素

propose：建议，提出，求婚

supplement：补充

supplant：取代

句子

We haven’t been around nearly as long as many other species, but in many respects we’ve accomplished more than any have before us.

humans are born quite helpless, far more so than any other primate, but, fairly early on, we start becoming quite smart, again far more so than any other primate.

she told me that their theory cannot offer an answer—likely as not, it’s a matter of pure genetic luck that became self-reinforcing.