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There was a couple of instances where a spider stopped in his track as soon as he notices me while an ant acts like I’m nothing else than an obstacle that can be climbed on.
Also, the bigger the spider is, the more cautious seems to be around people.
Is this a sign of various degrees of intelligence on insects or is it their natural predator nature that makes spiders to be more aware of their surroundings?
I’ve seen spiders stand still when I’m looking at them and start moving once my back is turned. I imagine they can see my eyes and recognise what they are for.
In: Biology
Spiders are predators which generally have better (or at least longer range/more detailed) eyesight than prey. Also, spiders are solo animals that have to keep themselves alive by finding food & assessing/reacting to threats, while it doesn’t matter if any given worker ant is stupid as long as the colony can react en masse in a way that helps the queen survive. Therefore, a spider is a lot more likely to notice and react to larger creatures, either as potential threats or as novelties.
Human intelligene is extremely general, while Insects have much more specialized intelligence. Ants are probably a little less complex than spiders, but they have very different roles and sensory abilities.
Ants are designed to function as a component in a larger machine. Most of their brainpower is centered around navigation, recognizing pheromones, and foraging. It doesn’t matter if individual ants die; the ants only need to respond if something starts eat a whole bunch of them. The basic evolutionary survival unit is the hive, not the individual. Ants have “formic acid” (its just latin for “ant acid”) which makes them a worse food than other bugs.
Spiders don’t care about pheromone trails, which leaves them more brainpower for predator/prey thoughts. Spiders usually have good eyes, which ants do not. Ants are too small to be good food for birds, but spiders are often bigger and juicier. A spider usually cares about living long enough to mate.
Insects are funky things. Ants and Spiders are both broad families. The generalizations I make here will not apply to all species.
First, a quick note that spiders are not insects. The lines that spawned the two groups diverged hundreds of millions of years ago before they even left the sea.
Now, the question. Spiders are individuals while ants aren’t. Each ant is a single part of a larger organism, the same way one of your cells is part of your body. It’s disposable and it acts like it. Even if it gets killed by something, another genetically identical ant will replace it and keep supporting the colony. Spiders are solitary animals. If that spider dies, that’s it for its genetic lineage. There will never be another one exactly like it and it wants to keep living for as long as possible to preserve it.
You’ll find that beetles and cockroaches will tend to run and hide when in your presence as well. Once again, they’re individuals, just like your spider, so they’ll want to stay away from the potential threat.
Spiders have incredible senses, vision is one of them. Beyond that though is the “spider sense” that Spiderman’s was based off of, their sense of touch. If a spider was large enough that it could reach up and touch space (62Miles/100km) then it would still be able to feel you walk up and brush a feather against it. Some might be able to feel Brownian motion, the jiggling of atoms and molecules. Hearing factors into this too, I’m not sure if they can hear like we can but they are very sensitive to vibrations through their sense of touch. Some are also able to fly using the earths magnetic field, spiders are incredible, thank God they aren’t the size of dogs or something.
Spiders are highly evolved and specialized, they are masters of survival while individual ants are not. Ants strength comes from their numbers and how they tend to act as one, almost like a hive mind, and since only the collective is important each member doesn’t need to be highly evolved to survive.
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