Monday, July 25, 2016

Two Kinds of Learning

One question about the formation of an alien civilization is the transition from evolution producing grasping appendages, easily controlled by the brain, and tool-using. Is it a big leap to go from having hands with thumbs and using those hands with tools? By tools, we do not mean socket wrenches and power drills, but the most simple tools imaginable. Rocks. Sticks. Shells.

This question is easily answered: tool-using is almost inevitable. The reason for it comes from the nature of the layered neural structure of the brain. It was realized long ago that a newborn infant of a mammal species does not come with all of the coding necessary for living and acting like an adult built in. This does not refer to the transition to adult reproduction, but to extremely basic activities. When a newborn herbivore is born, it knows enough to be able to suckle. This may involve being able to stand up and find the right spot on its mother, and then suck. But in the hours and days that pass, it learns to move more confidently, to eat other foods, to interact with other animals than its mother, and many more. Making sounds must be learned. And on and on it goes. This is the reason that there is an extended childhood period in mammals, and many other animals. It is not only that physical growth must take place, but also that patterns have to be established in the brain. The neural network at birth is largely blank, but it is filled in during the same period that physical growth happens. When childhood ends, the young creature is both physically able to act like an adult, but also is ready mentally, having processed enough information to have learned how to do most things an adult creature of that species does.

That learning takes place through play. By play, deliberate games between two or more creatures is not meant. By play is meant the experimental use of different activities, motions, postures or what have you. The human infant is likely the most primitive of all newborns. It does not have the ability to move, or even to grasp at the onset of its life. It moves its limbs and its brain notices the proprioceptive signals it is receiving along with tactile clues and visual clues, and puts them together into multiple layers of neurons, formerly inactive, but now dragged into use for motor activities. Everything else is learned like this. The newborn tries something and learns from the experiment, so that soon a more complex experiment can be done. There is also learning at a later stage from imitation, once the newborn has enough skills to be able to attempt to imitate. This imitation, along with experimentation, is accomplishing the same thing in the infant's brain. Layers of neuron are being activated, potentials adjusted, and so on. Actually in a human infant's brain, learning during the first three years involves the selection of neurons rather than solely establishing patterns of potentials for use. Many neurons die off in the infant brain and the volume left is filled by the growth of other neurons, which expand as they assume more dominant roles, such as longer distance communication between different layers and different regions.

Since there does not seem to be any alternative to a layered neural network for generating intelligent animals, this same type of learning should happen on any alien planet on its way to evolving intelligent creatures. Another form of interstellar convergence, perhaps? But the implications are immense.

There is no fixed program for a young creatures experimentation. Random inputs from the environment and from interaction with adult members or other young creatures lead to random aspects of the experimentation. There are no limits other than that provided by the physical characteristics of the creature and its species. Experimentation simply covers a wide variety of activities, and not solely those which have been successful among other creatures of the species. Experimentation extends to anything a youngster can do, and is not limited to those activities which adults are seen to be doing. The brain does not develop solely by imitation, but by experimentation.

Now it is time to explain what the two types of learning are. One type is what was just discussed, where a young creature of a species, here or on an alien planet, which is experimenting with anything in its environment and building up a repertoire of activities it will be capable of as an adult. The other type is learning as a species. There is a body of knowledge that can be imagined that the whole species has, which comprises all the activities that adults within that species have learned to do and are still capable of doing. Young creature's play, the first type of learning, naturally feeds into the second type, as anything a youngster learns to do, an adult can still do, with some limitations as to size of the creatures and the amount of growth they do and how the growth changes a few things like flexibility. By and large, when a young creature on an alien planet in a species with a larger brain picks up a rock or stick, it is not only learning how to hold it and throw it for itself, but for the whole species. In other words, tool use naturally falls out of the mandatory learning exercises that each competent young creature in an intelligent species with grasping appendages will do. If there are rocks in their environment, they will pick them up and hold them. They will drop them. They will, later on, toss them and later do some type of throwing. This is the dawn of tool use.

So to conclude, there is no barrier to the development of an alien civilization at the commencement of tool use, but it will coincidentally develop in a species with grasping appendages and a neural network. There may be many other barriers, but this is not one. Note that any tool use that progresses to adults serves as a beginning of the lore that is passed by imitation, so not only does play become written down in the brain of one young creature, it becomes part of the storehouse of survival tricks that the species has.

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