Any biologists out there? A question.

[TillEulenspiegel]

I recently saw a special about Australia on PBS. The topic was poisonous lifeforms on that continent. What I don't get is they would profile say a snake that is 50 times more toxic ( venom wise ) then a cobra. Then they show a monitor lizard eating the snake, hitting it against a rock first to kill it because if the snake bit the lizard it would die. OK this scenario was repeated numerous times with different animals. My question is , if the toxins are strong enough to kill the predator , why when the predator eats the poisonous animal is it not affected by the toxin? Enzymes or acid in the stomach, no direct contact with the blood stream?

Is it the same mechanism that allows domestic animals ( dogs,cats) to eat spoiled food that would kill a human , or at least make us very ill?

 

[TeaBag420]

It could be either acid or some other substance in the digestive system, or maybe the lizard was trying to kill the snake because a dead snake is easier to eat than a live snake.

Humans eat cobra venom as a recreational drug.

 

[Pantastic]

Swallow a load of insulin - no effect.
Inject a load of insulin into your bloodstream - coma and death.

The route of administration is important for many poisonous substances. The reason varies. It may be metabolised by acid or enzymes, it may not be absorbed in large quantities if at all, it may be absorbed but be metabolised or made safe by the liver (all substances absorbed in the gut go through the liver before entering the general circulation, intravenous administration bypasses this. It is known as 'first pass metabolism').

 

[Bikewer]

Most snake venoms are modified salivas, and assist in starting the digestive process on the prey animal.

As I recall, (and it's been many years since I read Ditmars) they are protiens that are readily broken down by the digestive process.

 

[SquishyDave]

Swallow a load of insulin - no effect.
Inject a load of insulin into your bloodstream - coma and death.

The route of administration is important for many poisonous substances. The reason varies. It may be metabolised by acid or enzymes, it may not be absorbed in large quantities if at all, it may be absorbed but be metabolised or made safe by the liver (all substances absorbed in the gut go through the liver before entering the general circulation, intravenous administration bypasses this. It is known as 'first pass metabolism').

What he said, someone wrote to Randi applying for the 1 million prize, their supernatural feat? Swallowing snake venom with no ill effects. Randi's response? Go away, everyone can do that!

Also note however, that if you happend to have a cut in your mouth or something, you may get some venom in your blood stream, and will get sick.

 

[Pantastic]

What he said, someone wrote to Randi applying for the 1 million prize, their supernatural feat? Swallowing snake venom with no ill effects. Randi's response? Go away, everyone can do that!

For $1,000,000 though - it was worth try, wasn't it?!

 

[Badly Shaved Monkey]

Just to clarify and make the connection that has not qute been made explicit.

As I recall, (and it's been many years since I read Ditmars) they are [proteins] that are readily broken down by the digestive process.

The venoms are proteins, like insulin is a protein hence...

Swallow a load of insulin - no effect.
Inject a load of insulin into your bloodstream - coma and death.

The route of administration is important for many poisonous substances. The reason varies. It may be metabolised by acid or enzymes, [thus] it may not be absorbed in large quantities if at all, it may be absorbed but be metabolised or made safe by the liver (all substances absorbed in the gut go through the liver before entering the general circulation, intravenous administration bypasses this. It is known as 'first pass metabolism').

But the reason why venom taken orally is not toxic is the one I have italicised, not the others.