Is that kind of information passed down genetically and if so, how does that work exactly? It seems easier to explain instinctive behaviors in other animals but weaving a perfectly geometric web seems so advanced it’s hard to fathom how that level of knowledge can simply be inherited genetically. Is there something science is missing?
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It is important to note that, much like many other things in nature, a spiderweb is simply a fractal… a structure that seems intricate on the outside but in reality are the result of a series of simple, repeating units/actions conducted on a larger scale.
We assume the information and instructions on how to build a web is passed down through their biology/genetics. but as far as HOW it works, well, we don’t know.
I don’t know enough to fully answer your question, but I do know it is coded into their brains, and that when spiders are given drugs it messes up their webs, as shown here.
https://www.newscientist.com/article/mg14619750-500-spiders-on-speed-get-weaving/
Nobody “taught” tipi to walk. When your leg muscles got Strom enough to hold you upright, they just held you up until you got it. It’s instinct
It’s probably very similar to how you were able to tie your shoes without thinking about it much after some practice. Human beings have some innate behaviors but unlike most animals we are largely born a blank slate and even many of our inborn characteristics are locked up only to reveal themselves upon maturation. If critical development goals are not met they may not manifest at all. For example, how do we prefer symmetry or specific traits in mate’s if we are unable to correctly process faces or interpret behavior.
Other animals are born with many of their behaviors baked in. So there is already some muscle memory or instincts and drives that account for a lot of the things they do. The brain structures are already there and while they likely need reinforcement and refinement they already have much of the circuitry intact. This has always been fascinating to me. When people say we are living things I don’t think we really even understand the half of it. There are so many factors involved in creating and sustaining a human consciousness. So many things can go wrong or corrupt the mechanisms that support our living experience of the world around us.
I had two cats and when they wanted something, they would look me in the eye. Anyone with dogs or cats has seen this.
How does a cat know to look me in the eye?
Even crazier to think about, butterfly can retain knowledge it learned as a caterpillar. So during chrysalis when it turns into a goop, that goop contains its memories.
It’s an instinctual behavioral, and we’re still studying how it works. We know that instinctual behavior is dependent on sensual stimuli (like it’s night time and the spider is on a branch) and different hormones.
What is interesting to me is that as humans we also have instinctual behavior dependent on our senses and hormones and I wonder how the differences in our modern way of life affect these behaviors.
DNA. The same way a bird knows to fly south and a salmon knows to swim up steam, even a newborn baby knows to find a nipple and drink the milk.
[What it’s like to be a ~~bat~~](https://warwick.ac.uk/fac/cross_fac/iatl/study/ugmodules/humananimalstudies/lectures/32/nagel_bat.pdf) …err… spider is largely unknowable from a human perspective, so to actually understand it we need to use some sort of reductionist analogy to something that we *can* understand. After all, you can’t know what it’s like to see the world through eight eyes or what it’s like to generate silk from your spinnerets.
But you can know that there are many things you naturally appreciate. Things that simply feel right, without some clear explanation as to why. If you’re throwing something, how do you judge distance? How do you decide where to aim or what to aim at? Why do some colors complement each other and others contrast? Why do some things feel imposing or threatening, while others feel comfortable and safe?
The analogies don’t track especially well because humans are far more complex creatures than spiders are. The instinctive responses when an infant treats a specific toy as their favorite toy are hidden behind learned associations (like familiar shapes and colors) and draws contrasts with other children who pick wildly different favorite items. But when you set aside the higher brain function required for learning and look at spiders, the only thing you’re left with is instinct. And far less complex instinct at that. The more you strip away learned experience and complex brain function, the more similar the animals’ behaviors are going to be—like how all newborns instinctively grasp at things placed in their hands.
So back to spiders. We can’t really know what combination of experiences and instincts drive a spider to build its web in any given shape be cause we can’t know what it’s like to be a spider. But it’s not terribly hard to see how an assembly of incredibly simple instincts can build a complex whole:
Again, imagine a baby. It’s not hard to understand and accept that infants have a grasping reflex. It’s not terribly complicated. So imagine a set of *new* instincts, added on top of grasping. And cap their complexity at the same height. Reach. Grasp. Pull. Repeat. And now the baby has a climbing instinct. Grasp. Carry. Release. Add a sense of “home” and your baby has a nesting instinct. They pick up the things they like, carry them home, and set them down.
A few simple instincts can easily explain the geometric complexity of a web. An urge to spin silk and to connect one piece to another. Add in a rough sense of how far apart individual strands should be (perhaps influenced by vision or the reach of its legs or the overall movement of the web under its own weight) and you’re going to end up with a distinctive, standardized pattern. And it’s only a very slight change in those instincts necessary to make a radical change to the overall pattern
The apparent “complexity” of spiders’ webs is a function of human observation. You see “beauty” in the end product and imagine the difficulty of building it yourself. But you’re not a spider. The process of a human building a similar structure adds a huge number of steps that spiders don’t take. You’d need to imagine your desired end product and investigate how it should be structured to hold that shape. And then you’d need to consider how you could safely build it without it collapsing along the way. And then you’d need to build it according to your plans without deviating from them. A spider just follows a simple repeating pattern that naturally creates the end result.
What is it like to do that? What is it like to be a spider and to build a web? It seems incredibly complex to you because you see tens of different types of webs and imagine it from your own perspective. But each type of spider can only build one type of web. The simple instincts that allow it are something you don’t have, sure, but that isn’t because they’re more complex than you. It’s because they’re *far* less complex. What you have is the ability to understand and build *every* type of web, plus cars and computers and mRNA messenger data. Your ability to develop and understand that variety of things means the abandonment of instinct in favor of learning. And spiders don’t have that.
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