万物简史 第488期:多灾多难的生命进程(8)

 　　By combining their isotope¹ findings with other fossil residues—pollen levels and so on, 把对同位素测量的结果和能够说明其他情况（如花粉浓度等）的别的化石残留物结合起来，

　　scientists can, with considerable confidence, re-create entire landscapes that no human eye ever saw. 科学家就能很有把握地重新构筑人类没有见过的整个场景。

　　The principal reason oxygen levels were able to build up so robustly² throughout the period of early terrestrial life 氧气之所以能在整个早期陆地生命的时期积聚到十分充足的浓度，

　　was that much of the world's landscape was dominated by giant tree ferns and vast swamps, 主要是因为世界上许多地方存在大量高大的桫椤和大片沼泽地，

　　which by their boggy³ nature disrupted the normal carbon recycling process. 它们天生就能打乱正常的碳再循环过程。

　　Instead of completely rotting down, falling fronds⁴ and other dead vegetative matter accumulated in rich, wet sediments⁵, 落叶和其他死去的植物性物质不是完全腐烂，而是积聚在肥沃而又潮湿的沉积物之中，

　　which were eventually squeezed into the vast coal beds that sustain much economic activity even now. 最后被挤压成大片的煤层。即使到了现在，那些煤层仍然支撑着大量的经济活动。

　　The heady levels of oxygen clearly encouraged outsized growth. 高浓度的氧气显然促使生物长得高大。

　　The oldest indication of a surface animal yet found is a track left 350 million years ago by a millipede-like creature on a rock in Scotland. 迄今发现的能表明陆地动物最古老的迹象的，是35000万年前由一只节肢动物似的家伙留在苏格兰一块岩石上的一条痕迹。

　　It was over three feet long. 它有一米多长。

　　Before the era was out some millipedes would reach lengths more than double that. 在那个时代结束之前，有些节肢动物的身长会超过那个长度两倍。

　　With such creatures on the prowl, 由于存在这种悄悄觅食的动物，

　　it is perhaps not surprising that insects in the period evolved a trick that could keep them safely out of tongue shot: they learned to fly. 那个时期的昆虫渐渐设计出一种对策，能够躲开飞快伸过来的舌头：它们学会了飞行。这也许是不足为怪的。

　　Some took to this new means of locomotion⁶ with such uncanny facility that they haven't changed their techniques in all the time since. 有的昆虫渐渐习惯于这种新的活动方式，而且达到了非常熟练的程度，自那时以来一直没有改变这种技术。

1 isotope   

n.同位素

参考例句：

• The isotope ratio is directly used for comparing oils or gases.同位素比率直接用于比较各种石油或天然气。
• How to apply a radio isotope?如何运用放射性同位素？

2 robustly   

adv.要用体力地，粗鲁地

参考例句：

• These three hormones also robustly stimulated thymidine incorporation and inhibited drug-induced apoptosis. 并且这三种激素有利于胸（腺嘧啶脱氧核）苷掺入和抑制药物诱导的细胞凋亡。 来自互联网
• The economy is still growing robustly, but inflation, It'seems, is back. 经济依然强劲增长，但是通胀似乎有所抬头。 来自互联网

3 boggy   

adj.沼泽多的

参考例句：

• Of, resembling, or characterized by a marsh or marshes; boggy. 沼泽般的，湿软的：类似沼泽地的，沼泽地所特有的；多沼泽的。 来自互联网
• The boggy is out of order, would be instead another one! 球车坏了，需要更换一部。 来自互联网

4 fronds   

n.蕨类或棕榈类植物的叶子( frond的名词复数 )

参考例句：

• You can pleat palm fronds to make huts, umbrellas and baskets. 人们可以把棕榈叶折叠起来盖棚屋，制伞，编篮子。 来自百科语句
• When these breezes reached the platform the palm-fronds would whisper. 微风吹到平台时，棕榈叶片发出簌簌的低吟。 来自辞典例句

5 sediments   

沉淀物( sediment的名词复数 )； 沉积物

参考例句：

• When deposited, 70-80% of the volume of muddy sediments may be water. 泥质沉积物沉积后，体积的70-80％是水。
• Oligocene erosion had truncated the sediments draped over the dome. 覆盖于穹丘上的沉积岩为渐新世侵蚀所截削。

6 locomotion   

n.运动，移动

参考例句：

• By land,air or sea,birds are masters of locomotion.无论是通过陆地，飞越空中还是穿过海洋，鸟应算是运动能手了。
• Food sources also elicit oriented locomotion and recognition behavior patterns in most insects.食物源也引诱大多数昆虫定向迁移和识别行为。