Another aspect to look at (or possibly this is two, tangled up together) is whether the behavior directly induces changes in the target in a generic fashion, rather than via a reception channel that receives the information and transmutes it into an effect. Allelopathic chemical release that kills off competitors is not communication. Tightly interconnected symbiotic associations of bacteria "communicate" chemically, but it's so optimized down and the feedback loops are so tight that it's more like they're a single organism. (Are hormone releases inside your own body communication?) Jumping at someone and waving your arms is communication, but it's similarly borderline, because you're probably invoking an instinctual reaction to move away from sudden large movements.
Communication should also involve some sort of feedback loop. What does the tree "expect" the results of the sound of a creaking branch to be, either consciously, or in that anthropomorphizing way we discuss fitness and evolution? Without an answer to that, I think we can file it away as "not communication".
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All that said, many trees absolutely do communicate with chemical signals. Famously, they may release warning chemicals during herbivore activity, and surrounding trees (conspecifics, but IIRC this can cross species boundaries) will ramp up production of defense chemicals.
Other plants use chemical signaling to attract predators of the herbivores that are munching on them.
And I believe I recall some process by which trees advertise themselves to mycorrhizal fungi that they would like to establish partnerships with, but I could be mistaken.
Your progression of thought makes a lot of sense. The question of whether any of this is deliberate, or a behavior encoded into genes and/or physical and chemical processes that can not be avoided. That being said, some people make an argument that our consciousness is also a chain chemical reaction with lots of feedback loops, and that our consciousness is just an illusionary byproduct.
I know that I presented multiple examples and all or not on the same level, no matter along which axis you evaluate them. The point is that deciding whether anyone/anything communicates is not an easy question to answer.
Another thing to chew on: Does communication involve a level of indirection? What if your chemical signal directly modifies a behavior pathway in the target, rather than starting a cascade that dispatches to that mechanism?
If it’s easier to study the language as a what you term “direct,” it seems less languagey, or whatever.
I personally think this distinction is distracting because you can always create a (large) bijection between encodings and their output when interpreted and then it looks “direct”, without actually writing the VM (just a huge lookup table).
I feel like smart languages just look nicer to use because they compress better (length to output blowup is exponential), and we think that seems more like human communication.
It could be that as humans we do not have enough intellectual power to understand the second example in terms of these laws. But then it could be argued that this is exactly what makes these two examples fundamentally different, since all human knowledge is limited by our intellectual capabilities.
Like a tree bearing bright red, juicy-looking fruits filled with sugar and vitamins?
Also disagree about the last statement, and not specifically in this case, but generally. It isn't necessarily about anthropomorphizing, but about using abstract and compact representation of what you're talking about. Humans emit sound waves, but we abstract that to segments, time-frequency descriptions, then phonemes, morphemes, ..., and finally language. You get the point. It's easier to reason about that way.
A tire bouncing along at 65 mph seems to have a lot of free energy (kinetic), as does one stuck on an icy slanted roof (potential) :). I may be unaware of the concept of "free energy" you are using here though. Can you point me to where I can find out more?
I absolutely agree that abstractions are necessary to efficiently convey concepts in a discussion. I also understand that abstractions are never perfect. What I wanted to really say is that I would be much more inclined to agree with the first and less with the second of these two statements:
Trees can transfer information to each other, and we have the ability to understand these mechanisms. Trees speak to each other in a language, and we can listen in.
It's a matter of phrasing, nuance, and insinuation. Different listeners may form different ideas when they read the above two statements.
The truck example is weird, cause it isn't trying to communicate. The person who made it may be trying to communicate something, but the truck would be a use of language, not using a language itself.
This is just an example off the top of my head.
This is a really interesting conversation and I think we will find that the true definition will elude a simple answer with solid boundaries.
You're distinguishing conscious intent and latent or subconscious intent.
Your body and instinct are very much intending to communicate that you are upset.
Having a temper is useful, but it wasn't designed in by any conscious entity, it's just that people who get angry tend to do better than people who don't.
You can argue that if you want. I'll argue the opposite: If a dog growls at me when I reach for his steak - but doesn't bite - I take that as him intending to inform me that he doesn't want me to take his steak.
It may be instinct, it may be adaptive, but it sure as hell was intended to get a message across to me.
Communication is about sending and receiving messages. A car tire cannot send or receive - it cannot communicate.
I think being clear that we are using a narrative where we empathize with something by imagining its features in terms that seem familiar to our own features (somewhat overlapping with “anthropomorphising”) is ok if done mindfully.
Do we mean that trees can relay information to each other, as well to other species? Sure, that makes sense.
For example, you could make a case that a large tree communicates with the saplings in the underbrush. By shading them, it is letting them know that it is the alpha individual in this area, convincing them not to grow.
We can also say that trees release chemicals that have an effect on surrounding life. This could also be called communication.
Finally, we could say that a loudly creaking tree is communicating to people around it that it is growing old, getting stress fractures, and could break off a branch that could pose a danger.
Any of the above could be considered communications.
To counter this, I could make a case that a truck tire can communicate just as effectively. It can cast a shadow which would prevent vegetation from growing. It could leach chemicals over time which would have an effect on the surrounding life. Finally, it could convey a threat by making loud bumping noises while it is bouncing towards you on a freeway.
Nature is interesting and complex. We continue to discover new and exciting things about how it works. I think anthropomorphising these effects makes them exciting, but does not necessarily add to how we understand them.