Snake poison 2 蛇毒

In fact, it would be an assistance to all carnivores though it would be a two-edged weapon when they fought each other. But, of the vertebrates, unpredictable Nature selected only snakes (and one lizard). One wonders saliva into why Nature, with respect from that of others, as other on the blood.
In the conversion of saliva into poison, one might suppose that a fixed process took place. It did not; some snakes manufacture a poison different in every respect from that of others, as different as arsenic is from strychnine, and having different effects. One poison acts on the nerves, the other on the blood.
因此，任何食肉动物有了毒液，都能从中获益。不过，当它们相互撕打时，毒液就成了利弊参半的武，可以杀死对方，也可以被对方的毒液杀死。然而，在脊椎动物中，大自然神秘模测地只选择了蛇（还有一种蜥蜴），人们弄不清楚大自然为什么在某些蛇的身上调制出如此高效的毒液来。
人们可能认为，唾液转变成毒液，其中有固定的程序。其实没有。有些蛇产生的毒液也在各方面与另外一些毒蛇产生的毒液不同，就像砒霜不同于马钱子碱一样。不同毒蛇产生的毒液产生的效果不同，一种毒液作用于神经，另一种毒液作用于血液。

New words and expressions 生词和短语

carnivore
n. 食肉动物
vertebrate
n. 脊椎动物
lizard
n. 蜥蜴
concoct
v. 调制
potency
n. 效力
conversion
n. 转变
arsenic
n. 砒霜
strychnine
n. 马钱子碱