Aside from perhaps snakes or sharks, few creatures fascinate the public as much as spiders and other arachnids do.
The reasons for this fascination are varied, but the fact that some arachnids are dangerously venomous is certainly responsible for a large portion of this interest many have.
As is so often the case, Mother Nature isn’t quite as scary as she seems, and spiders needn’t take up too much of your mental bandwidth. But we’ll try to answer some of the most common questions nature lovers (as well as those who are nature-nervous) have.
Are Daddy Long Legs the Most Dangerous Spider in the World?
No.
But let’s dig into this a bit. The answer is still going to be “no,” but it’s worth explaining the myriad reasons this little bit of mythology is so mistaken.
Let’s Get on the Same Page First: What Is a Daddy Long Legs, Anyway?
As we’ve argued elsewhere, common names are inadequate in many cases. Instead, when really looking into anything about the natural world, you should consider the scientific name associated with the species.
After all, this is the real name for the organism — the common name is just what laypeople call it. And that often varies.
For example, ordinary folks call just about any dark-colored snake seen in the eastern U.S. a “black snake.”
But in actuality, this term is often applied to any of four different species: Pantherophis spiloides, Pantherophis alleghaniensis, Lampropeltis nigra, and Coluber constrictor.
Daddy long legs exhibit the same basic problem: That term is applied to several different animals. But in this case, we’re not only talking about different species, we’re talking about animals that are on completely different branches of the tree of life.
Most commonly, the name daddy long legs is applied to the following three types of animals:
Harvestmen (Opilones)
Harvestmen are probably the group of animals to which the daddy long legs moniker is most commonly applied. But there are two important reasons that these animals are definitely not the “most dangerous (or venomous) spiders in the world.”
- They’re not spiders. They’re an entirely different type of arachnid. They’re closely related to spiders, but they’re not even in the same order.
- They have no venom glands. These peaceful little buggers primarily consume decaying organic matter.
These animals are completely harmless to people, although a few species may be able to produce poisons to dissuade predators from consuming them. This probably wouldn’t be a big deal for predators the size of humans, but — just to be safe (and civilized) — don’t eat them.
Cellar Spiders (Pholcidae)
Cellar spiders are also called daddy long legs, but they’re not the most dangerous spiders in the world (but hey, at least these arachnids are actually spiders).
They have fangs and venom glands, but their venom doesn’t appear to be dangerous or life-threatening. The few documented bites on record only caused mild pain or redness.
Crane Flies (Tipulidae)
Crane flies aren’t even arachnids — they’re harmless insects. They have no fangs or venom glands, and they’re of no real significance to the average person’s life (aside from the ecological roles they play).
Other Common Questions about Spiders & Other Arachnids
Now that we’ve put the great daddy long legs myth to rest, we can move on to some other common questions people have about spiders and their kin.
Spiders aren’t insects because they’re just different groups of animals that descend from different ancestors. It’s like asking why your dog isn’t a cat or your car isn’t a bulldozer.
But, what many people mean by this is, “what traits can help distinguish spiders from insects?”
This is a more reasonable question, but it’s still somewhat flawed — most insects have six legs, but the number of legs they posses isn’t the reason they’re insects.
Think about it: You can’t turn a spider into an insect by ripping off a couple of its legs in an attempt to achieve invertebrate alchemy.
The reason they’re insects is because they all descend from a single, “original” insect species.
We could discover an insect species with eight legs tomorrow. It’d be weird, and we’d have to figure out why this hypothetical species evolved an additional set of legs, but it would still be an insect. It wouldn’t become a spider because it evolved another pair of legs.
Nevertheless, the short answer is that most spiders have two body parts and eight legs, while most insects have three body parts and six legs.
There are myriad variables involved in these types of questions, but — for the sake or argument — most authorities agree that the Sydney funnel web spider (Atrax robustus) possesses the most virulent venom.
These kinds of questions are impossible to answer definitively. Not only do we discover new species every year, but some undoubtedly go extinct too — perhaps even including ones we never discovered.
For that matter, scientists are currently reorganizing the tree of life (in subtle ways), so the number of recorded species varies from time to time too.
All that said, there are somewhere in the neighborhood of 45,000 species.
Air enters a spider’s body via small holes called tracheal tubes. From there, the air travels to organs called book lungs, where air is allowed to come into contact with the spider’s blood (called hemolymph).
Yup. Whether they lose them in some sort of spider trauma or they jettison them voluntarily (usually to escape a predator), most spiders appear capable of regenerating lost legs.
No. All spiders produce silk, but not all spiders construct webs for catching food.
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Spiders may not be the cutest or cuddliest critters around, but the amount of fear they engender far outweighs the average threat they pose. Most spiders are completely harmless, provide important ecological services and want nothing to do with humans in the first place.
Yes, a few species are potentially dangerous, so caution is warranted. But there are far better things to worry about on a daily basis than the little house spider chillin’ in the corner of your basement.
