(Oops! One day late this week!)
A computer has some similarities to living organisms. Both produce something from, well, not very much. A computer program has data input from various sources, and produces output to various sinks or targets. A living organism takes in nutrients from various sources, and produces branches, leaves, fur, bones, blood and other organs.
Of course there are differences. A computer is much, much simpler than a living being, even single celled organism. A computer in general only has a relatively small number of parts, but the “parts” in a living organism number in the billions. And of course, living organisms reproduce, but that may change in the foreseeable future.
Some animals are sentient, but I’m not going to discuss that here. Maybe in another post.
A computer has hardware, software and operates on data. The data is either part of the software or read from buffers in the hardware. It stores its calculations in “memory”, which is special hardware with particularly fast access speeds.
The computer produces results by placing data into buffers in the hardware. This results in things happening in the real world, such as printing a letter or number on paper, or more frequently these days, on some sort of screen. It may also do many other things, such as control the flow of water by moving a valve or other control mechanism.
Computers communicate with other computers, by placing data in an output piece of hardware. The hardware is connected to a distant piece hardware of the same sort which puts the data into a buffer accessible to another computer. This computer may be a specialised computer that merely passes on the data. Such computers are called routers (or modems, or firewalls).
Computers, specialised only in their usage, are found in washing machines, cars, televisions, and we all these days have multi-functional computers in our pockets, our cellphones. It would be hard to find a piece of electronic equipments these days that doesn’t have some sort of computer embedded in it. Very few of these computers are completely isolated – they chatter to one another all the times by various mechanisms.
(Incidentally, I came across a bizarre example of connectivity of things the other day – a wifi teddy bear. Say you are sitting in the lounge and you want to send a message to your child who is in her bedroom. You pick up your tablet and send a message to a “cloud” web site. This sends a message to your child’s tablet which is in her bedroom with her. The teddy bear, which is connected to the child’s tablet by wifi, growls the message to the child. No doubt scaring her out of her wits.)
So in the current technological world everything is connected to everything else. Much like all the cells in a living being are connected to all the other cells in the organism, directly or indirectly. So how far can we take this analogy, where the organism is the network and the individual cells as the computers. (Caveat emptor – I am not a biology expert, so don’t take what I might say from here on as gospel).
A computer consists of hardware, software, and operates on data. A cell is sort of squishy, so “hardware” can only be a relative term, but a cell does have a relatively small number of organelles, such as mitochondria. The nucleus, which contains most of the genetic material, acts as the control centre of the cell, much as the CPU is the control centre of a computer.
The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression—the nucleus is, therefore, the control center of the cell.
In the cell, the genetic material is in some sense the software of the cell. It contains all the necessary information to create the cell itself or more interestingly the information needed to cause the cell to split into two identical daughter cells. This information is generally encoded in the DNA of the chromosomes.
The cell also contains, within the nucleus, an organelle called the nucleolus. This organelle (which is part of the nucleus organelle) seems from my reading to mostly relate to RNA, while the rest of the nucleus mostly relates to DNA, very roughly. RNA and DNA perform a complex dance called protein synthesis in organelles called ribosomes.
Cells produce chemicals, which can be consider analogous to computer outputs and receive chemicals from other cells, and so cells communicate, in a sense, with each other. Since all cells are equal genetically, it follows that a cell’s type, liver, skin, lung or brain neurone is determined by factors in its environment.
This only loosely true as each cells is the daughter of another cell and inherits its type, but in the early days of an organism’s life, before organs are formed cells do differentiate. Just as when computers were new, they were all very similar, keyboard, monitor, and beige case.
As the computer-sphere evolved, special types of computer evolved, such as routers and modems, and firewalls. Not to mention phones. Computers became specialised. Similarly cells become differentiated, some going on to become liver cells for example, and others brain cells (neurones).
When an organism is young and a cell divides both cells are the same type, but when the organism is very young there is no differentiation. The DNA in the cell contains the necessary information to determine the cell type and tissues and organs are created in the more complex animals.
This process obviously can’t be random, otherwise cells of the various tissue types would be all mixed up. It seems to me, maybe naively, that while the “program” for creating cells is in the DNA, some factors in the environment convey such information as how old the organism is, and what type of cell needs to be created.
We know from investigations into fractals that a simple equation can result in the creation of an image that looks very much like a tree or grasses and that small changes to the equation can lead to different tree or grass shapes. It is tempting to think that a similar process takes place in organisms – a general rule is given which results in the right sort of cells being produced in the right places.
The problem with the fractal idea is that it only creates simple shapes. An arm with fingers, skin and so on is beyond the capabilities of a fractal process so far as I know. Fractals don’t stop. Again, so far as I know there’s no way to iteratively create a tree structures with leaves.
So the “software” of the cell, the “program” embedded in the DNA doesn’t appear to be analogous to a simple computer program that draws fractals. Of course that doesn’t mean that we can never describe a simple organism completely in fractal terms, and create analogous distinct individuals.
It seems that a long as the analogy is not pushed too far, computers in a distributed network are reasonably similar to living organisms. Please note I am note referring to the fractal type computer programs, but am talking about the way that computers themselves in a network are somewhat analogous to living organisms. Primitive ones!