N.Wells
Posts: 1836
Joined: Oct. 2005
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1) You are (as always) confusing the map for the territory, the label for the actual thing. Your model does not simulate neurons in the hippocampus - you just have routines and variables that you have stuck labels on, with no attempt to simulate what actually happens. You have no ground-proofing and have not attempted to insert reality in any meaningful way. You might as well have a Global Climate computer model with variable called Storm that is initiated by a random number generator, rather than calculating storm parameters from underlying parameters.
2) You have not yet provided an operational definition for "intelligence", so no one, including you, can get a handle on what you are talking about. Your nonsense certainly doesn't apply to the standard definitions of intelligence.
3) Your computer model starts almost at the end of the process of brain evolution, so it would add little or nothing to the discussion even if it was accurate.
4) Those problems aside, it is obvious that the most primitive brains and their evolutionary precursors were heavily but far from solely involved with sensory input (so your various "criteria" are bogus).
Let's review what has long been known to everyone but Gary.
Once life existed, one of the earliest innovations must have been sensing and responding to stimuli. We see this in animals and plants, but also in protists and prokaryotes. At its basis, this is a taking or generating a chemical signal and generating a chemical response: e.g., sense light, generate growth hormone on that side. This does not involve motors until it reaches a relatively sophisticated level: much of this is simple chemical reactions.
Anything that is chemical is in a sense also electrical, and electrical signals can be processed and transmitted quite quickly, so cells that specialize in doing that (i.e., nerve cells) are advantageous. However, only the lineage leading to animals was able to capitalize on that, and only after that branch had already been taken: sponges don't have nerve cells. They also lack digestive and circulatory systems, so they don't have anything for an autonomous nervous system to control. They do have cells that can contract (hence myocytes, or muscle cells), but they rely on their own albeit weak signalling abilities, which are part of the basic capabilities of all cells.
Nerves transmit electrochemical impulses, from responses to stimuli, both chemical, electrochemical, and physical (touch, sound, light), and to muscles. Part of that is simple transmission, without processing : signal generation over here can generate a response in a cell over there. This has obvious advantages, even for a sessile creature, and even when no "motors" or muscle cells are involved ("Food! - Start producing digestive enzymes").
Cnidarians and ctenophores create nerves and a nerve net (rapid signal transmission and a transmission system). Presumably the former comes first, and the second follows almost immediately. There is still nothing in the way of ganglia or brains, so very little processing happens beyond automatic generation of a consensus responses from the nerve cells. Neurons collect, process, and transmit those signals: in simplest form, they are just a communications relay station.
The next step up is to collect a mass of neurons together, for ease of intercommunication. These are ganglia, and we have reached the stage where we can talk about processing signals rather than just transmitting them. This is particularly valuable in terms of triggering muscle cells to do something.
However, most of the jobs of ganglia in no way involve anything that can be referred to as intelligence, as most ganglia are part of the autonomous (or peripheral) nervous system. This is concerned with the most basic of functions for the operation of the individual organism, which require no choices whatsoever: "beat now, beat now, beat now" once you have at least a precursor for the heart; "food coming, release enzymes, start peristalsis" once you have a gut. (Again, note that the simplest animals do not have guts, hearts, circulation systems, or nerves.)
The next step up from the thoughtless responses from ganglia are to collect the ganglia into a centralized cluster, i.e. a brain. Earthworms have lateral peripheral ganglia, which communicate to two large ganglia on either side of its head. These are approaching being a brain, but they are not in complete control: they don’t exert complete central control, because the ganglion in each body segment receives and processes sensory information independently.
Obviously, although that works for the worm, it is not especially efficient. It would be like having an army run by sergeants, who send their information and decisions up to a panel of generals, who then render suggestions.
Once you have a brain, you have the opportunity for more interconnections between the neurons, thereby allowing for more complex processing, including primitive thinking. Nonetheless, animals suggest that a lot of primitive brain power is going towards interpretation of complex signals and generation of complex sequences of responses, rather than generating creative responses based on retrieved memories.
An organism can do a fairly sophisticated job of navigation by following simple sets of rules (e.g. look at maximally efficient detritivore tracks) or by random walks followed by retracing chemical trails, such as ants). However, by the level of navigation involving learning and recognizing landmarks, choosing routes, and perhaps especially correctly guessing shortcuts, we can legitimately talk about intelligence at work. However, this is a level of sophistication well beyond the evolution of the animal kingdom, let alone the origin of life.
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