科学美国人60秒 SSS 热带森林存储人类历史

This is Scientific American's 60-second Science, I'm Susanne Bard¹.

If you watch nature documentaries, it's easy to come away with the impression that lush tropical forests have been largely undisturbed until modern times.

"Tropical forests have sort of long been considered to be these pristine² wildernesses³ that humans haven't really touched until recent industrial forces have started to invade them and challenge them with 21st-century capitalism⁴."

Archaeological scientist Patrick Roberts of the Max Planck Institute for the Science of Human History.

"However, in the last two decades, archaeological data have shown that, actually, human societies have occupied and modified these environments over many millennia⁵."

Roberts says some of the trees alive in tropical forests are up to a thousand years old. And they're sort of like time capsules, storing a record of past human activity in their tree rings, chemistry and DNA⁶.

"So we wanted to see how different existing methods might come together to explore past tree populations, tree growth, tree ages by looking at the largest witnesses of the changes in human activity in the tropics—the trees themselves."

For example, indigenous⁷ peoples of the Amazon basin cultivated Brazil nuts for thousands of years. Roberts's colleague Victor Caetano-Andrade analyzed⁸ tree rings to determine the age and growth rates of Brazil nut trees near the city of Manaus. He found that many trees were established in the late 1600s, but there was a steep drop-off in new trees around the middle of the 18th century.

"As colonial communities came into Manaus and developed the city, they drove indigenous people out, often killing⁹ them. And what Victor found is that, actually, their growth slowed after this period without these traditional management strategies. So these Brazil nut trees that were still standing¹⁰ near Manaus today are actually affected¹¹ by these pre- and postcolonial changes in human settlement and activity."

Another example is how communities selected for genetic¹² traits in a variety of tropical trees, such as the cocoa tree—used, of course, to make chocolate.

"A more detailed¹³ full genome analysis of this plant has shown that humans may have even selected genes¹⁴ that reduced bitterness and improved its resistance to disease for their own economic benefit."

The study is in the journal Trends in Plant Science.

Roberts says recognizing tropical trees as time capsules of cultural heritage gives us yet another reason to protect them.

"Not just because of their ecological¹⁵ benefits, which are hugely significant, but also the information that they store about human history, about our past."

Thanks for listening for Scientific American's 60-second Science. I'm Susanne Bard.

这里是科学美国人——60秒科学系列，我是苏珊娜·巴德。

如果你观看自然纪录片，很容易就会产生这样一种印象：茂盛的热带森林直到现代才遭到大范围破坏。

“长期以来，人们一直认为热带森林是人类未曾触碰的原始大地，直到最近，工业力量才开始入侵这里，并利用21世纪的资本主义发起挑战。”

马克斯·普朗克人类历史科学研究所的考古学家帕特里克·罗伯茨说到。

“然而，在过去二十年，考古数据表明人类社会占领并改变这些环境的历史已有数千年。”

罗伯茨说，热带森林中现存的一些树，树龄可达上千年。它们有点像时间胶囊，将远古人类活动记录在年轮、化学物质和DNA中。

“因此，我们想了解现在的不同方法如何共同探索古树的数量、生长和年龄，方法是通过观察热带地区人类活动变化的最大见证者——树木本身。”

例如，亚马逊盆地的土著人种植巴西坚果已有数千年的历史。罗伯茨的同事维克托·卡埃塔诺·安德拉德分析了年轮，以确定马瑙斯附近巴西坚果树的年龄和生长速度。他发现许多树木种植于在17世纪末，但在18世纪中叶左右，新树的种植量急剧下降。

“随着殖民者进入马瑙斯并开发城市，他们驱逐并时常杀害土著人。维克托发现，这段时期后，传统管理策略失效，树木生长速度下降。因此，这些仍然矗立在马瑙斯附近的巴西坚果树，实际上受到了人类寄居和活动在殖民前后变化的影响。”

另一个例子是，人类如何为可可树等各种热带树木选择遗传特性，当然，这是用来制作巧克力。

“对可可树更详细的完整基因组分析表明，人类甚至可能为了自身的经济利益而选择减少苦味和提高抗病性的基因。”

这项研究发表在《植物科学趋势》期刊上。

罗伯茨表示，将热带树木视为文化遗产的时间胶囊，给予我们另一个保护它们的理由。

“不仅因为它们具有非常重要的生态效益，还因为它们储存了有关人类历史和我们过去的信息。”

谢谢大家收听科学美国人——60秒科学。我是苏珊娜·巴德。

1 bard   

n.吟游诗人

参考例句：

• I'll use my bard song to help you concentrate!我会用我的吟游诗人歌曲帮你集中精神！
• I find him,the wandering grey bard.我发现了正在徘徊的衰老游唱诗人。

2 pristine   

adj.原来的，古时的，原始的，纯净的，无垢的

参考例句：

• He wiped his fingers on his pristine handkerchief.他用他那块洁净的手帕擦手指。
• He wasn't about to blemish that pristine record.他本不想去玷污那清白的过去。

3 wildernesses   

荒野( wilderness的名词复数 )； 沙漠； （政治家）在野； 不再当政（或掌权）

参考例句：

• Antarctica is one of the last real wildernesses left on the earth. 南极洲是地球上所剩不多的旷野之一。
• Dartmoor is considered by many to be one of Britain's great nature wildernesses. Dartmoor被很多人认为是英国最大的荒原之一。

4 capitalism   

n.资本主义

参考例句：

• The essence of his argument is that capitalism cannot succeed.他的论点的核心是资本主义不能成功。
• Capitalism began to develop in Russia in the 19th century.十九世纪资本主义在俄国开始发展。

5 millennia   

n.一千年，千禧年

参考例句：

• For two millennia, exogamy was a major transgression for Jews. 两千年来，异族通婚一直是犹太人的一大禁忌。
• In the course of millennia, the dinosaurs died out. 在几千年的时间里，恐龙逐渐死绝了。

6 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

7 indigenous   

adj.土产的，土生土长的，本地的

参考例句：

• Each country has its own indigenous cultural tradition.每个国家都有自己本土的文化传统。
• Indians were the indigenous inhabitants of America.印第安人是美洲的土著居民。

8 analyzed   

v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析

参考例句：

• The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
• The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程，因为对他来说，爱是个不可分析的迷。 来自《简明英汉词典》

9 killing   

n.巨额利润；突然赚大钱，发大财

参考例句：

• Investors are set to make a killing from the sell-off.投资者准备清仓以便大赚一笔。
• Last week my brother made a killing on Wall Street.上个周我兄弟在华尔街赚了一大笔。

10 standing   

n.持续，地位；adj.永久的，不动的，直立的，不流动的

参考例句：

• After the earthquake only a few houses were left standing.地震过后只有几幢房屋还立着。
• They're standing out against any change in the law.他们坚决反对对法律做任何修改。

11 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

12 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

13 detailed   

adj.详细的，详尽的，极注意细节的，完全的

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。

14 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

15 ecological   

adj.生态的，生态学的

参考例句：

• The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
• Each animal has its ecological niche.每种动物都有自己的生态位.