Incongruously Poisonous

To answer the question from my previous post… Yes, there are snakes that are actually poisonous to humans!

Where do they get their toxins from?

The first thought would be “If snakes can make venom then they can just brew some nasty toxins and become poisonous”, but it doesn’t work that way, these snakes get their toxins from the frogs and toads that they eat. The toxins from the toads are extracted during digestion and stored in the nuchal glands which are present in the neck region. Even the Keelback hatchlings can be poisonous, the mother can pass on some of her toxins to her babies!

So, the snakes and the toads have the same toxin?

No, the toxin in the nuchal gland is modified by the snake and is made more toxic to the snake’s predators. The snake also seems to be aware of its toxin resources, a threatened snake would defend itself when it has the stored poison but would back off when it has run out of them!

Why do these snakes need poison when they already have venom?

These Keelbacks are rear-fanged snakes, which makes it difficult to successfully envenomate a predator larger than them also, their venom is not very fast acting.

The fangs of a rear-fanged snake such as this female African Boomslang are situated at the back of their head. These snakes really need to bite on to their prey to inject enough venom.

When threatened, these Keelbacks tend to squirt out the toxins from their nuchal glands. If the toxin doesn’t land on the predator’s eye, it will be absorbed by the skin causing irritation and if untreated, it can be fatal.


Since most people in the world don’t prefer eating snakes, we can’t say for sure that there are only a few poisonous snakes, there might be more waiting to be discovered out there. Unless we go eating all of them, I think it’s safe to say that we will be fine.
So next time someone says there are no poisonous snakes or otherwise, you’ll have valid points to make…


Image credits: Pinterest and Google

2 thoughts on “Incongruously Poisonous

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s