时差N小时 巨型昆虫的进化与消亡(下)

These changes, which gave birds greater facility for flight, made them more effective predators¹. It’s not difficult to imagine that they feasted on giant insects.

这些变化明显增强了鸟类的飞行能力，进而提高了它们的捕食效率。不难想象，他们开始将大型昆虫作为猎捕目标。

That’s one theory, at least. Another holds that rather than eat giant insects, prehistoric² birds simply out competed them. Both birds and giant insects ate smaller insects that existed alongside their super-sized cousins. Evolution may have enabled birds not only to dine on giant insects but also to consume smaller insects and deplete³ their competitors’ food source.

至少，这是其中的一项理论。另一种理论认为，与其说史前鸟类以巨型昆虫为食，不如说其淘汰掉了巨型昆虫。鸟类和巨型昆虫均以较小昆虫为食，而小型昆虫的栖息地又临近大型昆虫。进化后的鸟类不仅能够捕食巨型昆虫，同时还能捕食小型昆虫，从而消耗竞争对手——巨型昆虫的食物来源。

1 predators   

n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）

参考例句：

• birds and their earthbound predators 鸟和地面上捕食它们的动物
• The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》

2 prehistoric   

adj.（有记载的）历史以前的，史前的，古老的

参考例句：

• They have found prehistoric remains.他们发现了史前遗迹。
• It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。

3 deplete   

v.弄空，排除，减轻，减少...体液，放去...的血

参考例句：

• Most native mammal species have been severely depleted.大多数本地哺乳动物的数量都已经大大减少了。
• Elastic collisions deplete very little of the electron's energy.弹性碰撞中电子减少的能量非常少。