At what age would a child know enough to be scared of a poisonous snake etc.?

It needs to be bitten.

Unfortunately, in some cases, loli is correct. Some never learn unless first hand experience gets them. Even then, they may not. Case example, Steve Irwin.
If you are asking when should one endeavor to teach children respect for animal defenses, no age is too soon.

Unfortunately, my daughter is a Steve Irwin. She has been bitten by two squirrels, some snakes, a praying mantis, um, thinking.
Both squirrels she was trying to help. One had its leg caught between crossed branches, and she thought it would appreciate a bare handed human coming to grab it. The other one was injured.
She was attacked by a wild turkey once, but all he did was kick snow at her. It was an early snow, and she thinks he was pissed about it.

@ragingloli I don’t know if I agree. A 7 yr. old would know if told or read enough times, or saw movies like “Jaws”.
@Patty_Melt What was the age of your daughter?

I’ve flagged the OP for editing by the way

My daughter is 16, and I’m not sure she gets the importance of caution yet.
The squirrels bit her when she was eleven and fourteen. There was a snake when she was fifteen. I give her the business each tim, so I am sure there are times she just didn’t tell me.
She isn’t stupid. She gets top grades, and could put adults to shame when she was in primary school. She just seems to feel nature will not kill her.
I blame movies which humanize animals.

Depends on whether the specific child has learned to fear snakes yet or not, which does not have to me from first-person experience. It is not really a function of age per se.

Here is a related article on the general subject.

@Patty_Melt You’re right it takes a lot of work to sensitize kids to danger.
@Zaku I agree it is not a question of age, at all, but under a certain age there is no understanding what danger means. A 6 month old wouldn’t remeber having been bitten by a dog, snake or whatever other animal. That’s what I meant with my OP. Thanks for the article.

My son was different. From around nine months I started teaching him by staging accidents. I made it look like I did something clumsy, and accidentally touched a kitchen outlet. I made a buzz sound, screamed, cried, told him it hurt, then warned him to never touch those. That way he got to witnees an accident, and the warning carried some weight. I did similarly with stove, oven, sharps. It worked like a charm.
With my daughter, she found it amusing, and wanted me to ” do it again.”

So, why would anyone say You don’t need to train kids about danger, whatever kind of danger, because they’d just know, it’s in the DNA

Beeeee….
cause
they’re deluded?

It’s either that or trying to discredit the medical field?
Fake news, just like “Mr”. Obama”, and “Mr”. Trump” etc.
https://nypost.com/2017/10/21/science-confirms-spiders-and-snakes-are-innately-terrifying/

So, 6 months old are terrified of snakes and spiders the ones who end up becoming fearless must have undergone some therapy or just miraculously… ?
I should correct myself it’s not any kind of danger they’re saying only snakes and spiders. It’ still sounds like garbage.

I was never scared of snakes until I cornered one, by accident, and I saw its fangs, and the tight, glistening bulges at the base of each fang.
I was fascinated by spiders until one in my shoe bit me.

When my daughter was a baby our house was invaded by a bazillion baby spiders. I walked into her room and found her poking the floor with her finger. She was trying to poke a little baby spider that was crawling across the carpet. EEGADS!
I still cringe when I see things she is willing to pick up.

I’d say they should have been taught and the lesson sunk in by the age of 2–3.

My 30 year old son loves spiders and snakes and all manner of creepy crawly things…. especially snakes. Always has. But he also has brains and is well educated on different snake species.

I’m not particularly afraid of snakes, and generally, not afraid of spiders either. If they’re in my house, and they aren’t a brown recluse, I will go so far as to rescue them, like if they’re stuck in the sink.

Gosh, at our most recent family reunion Rick’s 40 – something year old daughter wound up with a teeny tiny spider on her shirt. She screamed like she’s been shot and whisked the spider off. It landed on the floor and started coming toward me. She and her daughters were screaming ”LOOK OUT VAL!! IT’S COMING TOWARD YOU!!! HE’LL CLIMB ON YOU!!!”
I didn’t react at all, just looked at them and said, “And what, exactly, do you think he’s going to do to me?”

Spider bites make me swell up and turn yellow. I have to get a shot.
Some people have perfectly good reason for freaking out.

not spider bites, gamma radiation.
and not yellow, but green.
get your hulk right