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[ti:Snake Poison]
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[00:01.50]Lesson 20
[00:03.44]Snake poison
[00:11.03]What are the two different ways in which snake poison acts?
[00:17.22]How in came about that snakes manufactured poison is a mystery.
[00:22.09]Over the periods their saliva, a mild, digestive juice like our own, was converted into a poison that defies analysis even today.
[00:32.88]It was not forced upon them by the survival competition;
[00:36.57]they could have caught and lived on prey without using poison, just as the thousands of non-poisonous snakes still do.
[00:44.90]Poison to a snake is merely a luxury;
[00:48.40]it enables it to get its food with very little effort, no more effort than one bite.
[00:55.01]And why only snakes?
[00:57.76]Cats, for instance, would be greatly helped;
[01:00.78]no running fights with large, fierce rats or tussles with grown rabbits--just a bite and no more effort needed.
[01:09.71]In fact, it would be an assistance to all carnivores though it would be a two-edged weapon when they fought each other.
[01:17.73]But, of the vertebrates unpredictable Nature selected only snakes (and one lizard).
[01:24.77]One wonders also why Nature, with some snakes concocted poison of such extreme potency.
[01:32.94]In the conversion of saliva into poison, one might suppose that a fixed process took place. It did not;