Showing posts with label genetics. Show all posts
Showing posts with label genetics. Show all posts

Thursday, September 9, 2021

Small, Old Civilizations

Since there are no signatures, at least bold, obvious ones, that there was a large, ancient civilization before our era, the possibility of a small, ancient civilization needs to be examined. When we say small, we mean one which stays below some fixed population count. The population limit is small compared to modern populations, or even ones of a century or two ago. The number might be tens of thousands or hundreds of thousands of people.

Why would a civilization keep its numbers down, especially in early eras when the concept of resource exhaustion would not have been known? What motivations could there be for limiting a population? Civilizations, especially early ones, are led by some individual, or in rare cases a small group. So the question really is, why would a leader take actions to limit the population of the people he governed? The usual case, in our history, is that leaders never do such things. Perhaps they might be forced to.

Suppose a tribe lived in a river valley, and a chieftain long before had established a belief system which included the rule that anyone emigrating from the river valley was insulting the chief and betraying his tribe. It would be easy to have this incorporated into the theology that was around at the time, as theology has the knack of adapting to rulers' desires, although not in an obvious manner. So, if this one chieftain had felt insulted and started this tradition, the population outside of the river valley would stay at zero. Perhaps the tradition includes any secretive emigrants being hunted down. With this rule in place, there is no possibility other than a limit to total population.

A river valley such as the one in this example would have a certain amount of water flow, from the river and from rain, and that might be the limiting factor in how much food could be grown. Some years might be better than others, but when a bad year came, or a stretch of drought years, the limit would be unstretchable. After some decades or even centuries, it would be known just how many people could live without threat of starvation during the bad periods, and some sort of reproductive control might be needed to accomplish this. Shaman medicine might come into play here, if an herb was found which caused temporary infertility, without much else in side effects. The civilization would have to have some rules for who is allowed to have how many children, but they could be any type of rules at all, as long as the maximum was not exceeded.

Thus, it is not difficult at all to envision a civilization which had a limited population over a long period. It just needs a geographic limitation enshrined in the tradition and the religion, and a means of controlling reproduction, such as a herb or other plant product. There might be other means as well.

The implications of such a civilization are substantial. If the civilization lasted for many millennia, scientific knowledge and technology would be developed. It might take ten or a hundred times as long as if the entire world were full of people developing scientific concepts or engineering solutions to problems, but there does not seem to be a critical mass of people below which science cannot develop. Perhaps there is one, but it might be ten thousand people, and the civilization could be imagined to be larger than this. So, slowly, slowly, technology grows inside this ancient civilization. But because of the limit in population, it would not grow in a wide a domain as it could were the population a hundred times larger. Certain things would be developed, and that field might be explored, and then some time later, a different advance might be made. So, while technology was developing in the small civilization it would not be uniform.

Technology does not develop in a chaotic form, as there are certain advances which have to be made in order to enable the research needed to develop other advances. In our world, genetics had to wait because the technology of DNA analysis was needed first, and it needed computation and some materials developments. In a limited civilization, these pathways would be much more severe. If the civilization lasted only five thousand years, perhaps only some basic chemistry and physics would be accomplished, together with some engineering capability. It is quite likely that working with natural materials like rock of different types would be one that would be developed earlier in the civilization's history. Thus, finding some evidence of precision rock machining is more likely than, for example, asphalt reside from airport landing strips. Carefully thinking out what could be developed in stages might lead to some more clues as to what signatures there could be from small, ancient civilizations.

The challenge of finding such signatures is daunting. Even if someone could come up with a proposed list of them, there is the difficulty of knowing where the civilization lived. In our example, there is only one spot on planet Earth where the signatures would be found. Even if there were two or three, it is still a formidable problem to find them. One could try and figure out where the civilization would choose to be, but that makes the assumption that they searched around over some wide area and picked the best spot and settled there. Starting the settlement seems more likely to be a matter of chance. It might depend on where some proto-humans were when some critical mutation increased their intelligence or when they figured out how to grow a crop on a river delta where they could stay, without continuous migrations using slash-and-burn agriculture. Any number of unguessable things could lead to the foundation of the home valley of the civilization. Thus, it might be necessary to search all river valleys for their location.

It might not have been a river valley where they decided to stay, although that seems a likely choice. A lakeside location is possible. If agriculture was not as dominant as we might guess, a prolific forest area might be a choice. Again, some careful thought is needed to first construct a list of the types of areas that might be chosen, and then to narrow down the possibilities for each. An even greater problem is that this civilization is supposed to have existed tens of thousands of years ago, when the surface of the Earth was a bit different than it is today. So some geology would need to be done as well. This is indeed a difficult problem.

Sunday, May 3, 2020

Biowarfare and Alien Civilizations

Warfare has been so common through the last several millenia on Earth that it might be thought to be inevitable that it would occur on all exo-planets with thriving alien civilizations. The killing of other individual aliens and the destruction of their property, on a large scale, can be motivated in many ways. It might be the equivalent of envy, hatred, greed, love of destruction, desire for power, wishing to spread one's world-view or religion, fear, and likely others. Since there are so many reasons for having a war, wouldn't there necessarily be some?

The antecedents of mankind's love for war might be their evolution as hunters. Killing large game and killing other aliens is not so much of a jump in direction as eating only fruits and vegetables and then starting to kill other aliens. Can only omnivores evolve intelligence and eventually a civilization, or could herbivorous creatures do so as well? 

Perhaps this question should be asked in a reverse manner. Can herbivores who develop tree-climbing ability and then grasping appendages stay herbivores, or would the ability to reach nests start them on the path to eating eggs, newborn animals, young animals, and lastly full-grown animals? Raiding nests on the ground might start them off on the same evolutionary track. Given the nutrient value of eggs and young animals, this track provides significant advantages, and therefore it is likely that such creatures would not stay herbivores, but would evolve, step-by-step, into hunting animals, and then into tool-using hunters. This is the likely step before killing one another, and then as groups form, so does the concept of warfare. Warfare is therefore likely in the history of most alien civilizations in the galaxy.

Technological determinism says that society is shaped by the level of technology it has achieved. Warfare, as one feature of society, is also determined by technology, and as technology travels from stone and wood tools, to metals of ever increasing strength-to-weight ratio, to combustion in various forms, and onward to machinery, so do the tools of war. In the later stage of the industrial era, on planets with uranium in the ground not already decayed into too much U-238, nuclear weapons should be invented, and then the society would quickly realize the disutility of weapons of so much destructive power and requiring so much expertise to use. 

There is likely an overlap between the genetic era, when biology is being understood in many of its details, a precursor to genetic technology, and the last stages of the industrial era, that of electronics, automation and robotics. Breeding of plants and animals would have been proceeding for the whole age of the society, using trial-and-error techniques, and as the understanding of disease becomes widespread, the concept of bioweapons does also. One can use trial-and-error methods to breed disease organisms as well as socially useful organisms. Initially, the analogous use of bioweapons would be tried, similar to chemical weapons, such as by explosive canisters or sprays, applied on the front lines of armies, but these methods have quickly-discovered drawbacks of self-contamination and countermeasues, such as personal protective equipment.

Contagion is a more appropriate use of spreading a bioweaponized virulent organism. If one region has a particular and unique type of crop, which provides a substantial fraction of the nutrition for this region, then an enemy region could attempt to devise infectious organisms which would spread widely through the crop, eliminating its value. If the crop was annual, the yield would plummet. If it was a perennial, the productive plants would fail to grow the product, or even die. No such type of attack would work if all regions grew the same range of crops, however. Analogous arguments would work for animal husbandry as well.

If there was some unique genetic characteristic that most of the inhabitants of one region possessed, and it were possible to breed an infectious organism that would only attack those inhabitants with the particular feature in their genes, an analogous attack could be made. However, if this genetic dissimilarity is not wide-spread, or no organisms can be made to focus on one that exists, biowarfare can only be accomplished through a more organized and insidious means. If contagion is the means by which the infectious organism spreads, then the attacking society must somehow have some characteristics that allow it to be only slightly affected, which the opponent must have the opposite characteristics. If the disease is mediated by insects which live in unhygienic environments, a hygienic region could attack a unhygienic one. The reverse is obviously not true, but if there is any infection-carrying options, such as pets of some particular type, these might serve as the vectors for the disease contagion. 

If the disease spreads only from dead bodies of victims, then burial details might make one region more susceptible to being the target of a biowarfare attack. However, this is something that could quickly be recognized and altered, so such an attack is problematic at best.

If the disease spreads only through direct sharing of bodily fluids, such as blood to blood, it is not likely that it could be transformed into a bioweapon. There might be the equivalent of Earth's mosquitos on some particular exoplanet, but insect control is not difficult in an industrial civilization. Thus these diseases also would not serve well as bioweapon candiates. But if the disease could spread through indirect sharing of bodily fluids, or even without bodily fluids being used on the whole transmission path, then there might be a possibility of a bioweapon. If the infectious organism can spread through touch, or live on any kind of common surface for a period of time long enough for mutiple aliens to touch it, or travel on dust particles or water micro-bubbles, then the disease could act to have a large degree of contagion. 

If the attacking region has a way to prevent such sharing because of social customs or other social controls, and the target region has different customs or no ability to install social controls, then the opportunity for a bioweapon war might be possible. It would not look like any other type of war, as there would be no battleground or front lines, no armies involved in mass attacks, no industrial war machines being used, and perhaps even no declaration of war. The only thing that would happen would be one region would succumb to a high level of fatality, while another would not. Then economics would finish off the struggle between these two regions.

Could one or more biowarfare wars doom an alien civilization to collapse and never reaching star travel? This is not likely to happen, as social controls can defeat a bioweapon attack or serve as a protection of an attacker, so society might have some economic disruption during the period of the attack, but the attacker would not lose their grip on technology, nor suffer a great deal of economic disruption, and would be able to control the other region or regions and continue to pursue technology and eventually get to asymptotic technology. After this point, infectious organisms are easily controlled and no biowarfare would make sense, as antidotes and antigens could easily be generated as soon as the infection was noticed.

Monday, January 27, 2020

Chromosome Genetics

Knowledge abounds here on Earth about the number of chromosomes humans have and how gender is determined by whether a fertilized egg cell has an XY or XX chromosome pair. It's less well known that cell division includes the opening up of all nuclear DNA pairs and the splitting of them into two batches before replication. Even less well known is how hard it is, given today's technology, to separate chromosomes so they can be accessed individually.

It is not exactly clear if there is any other way of harnessing the protein synthesis control capabilities of DNA so that alien cells might have a different way of doing it. Nor even is it known if there are alternatives to DNA to carry genetic information. Genetics in this area is like exo-planetary studies before any exo-planets were discovered. Everything is speculation.

These two questions are somewhat independent. If an alien planet had non-DNA genomes, that still does not mean that they would not have all the genetic information divided up into chromosomes. The alternatives are to have more than one nucleus in the cell, with perhaps one chromosome in each, or to have one nucleus with only one chromosome pair having all the DNA or its equivalent. Why did Earth evolve multiple chromosomes, or rather, why don't all species have just one large circular chromosome as do many single-celled organisms? What is the evolutionary advantage and would it be universal, meaning on other planets as well?

Among contemporary bacteria, there are some with one, two or more circular chromosomes, some with linear chromosomes, and some with a combination. After billions of years of evolution, the competition for a chromosomal shape has not been won by any arrangement, so for bacteria and other prokaryotes at least, there must be little evolutionary advantage between them. This is not true for eukaryotes, multi-cellular organisms, which all seem to have linear chromosomes. Most eukaryotes also have some legacy circular chromosome material, located in the mitochondria or elsewhere, which reproduce independently of the nuclear DNA during cell division.

One advantage is obvious. To have genetic information for many different types of cells, as well as the signaling information for organizing them, there must be much more information, and a circular chromosome or a single linear chromosome with all this information would simply be too large to fit into the nucleus, or for the meiotic proteins to handle. Having everything in large numbers of diverse mitochondria also seems evolutionarily difficult, for the organization of cell replication. So, using DNA or anything else, it appears likely that alien species will have multiple linear chromosomes.

Alien geneticists may run into the same problem that Earth geneticists have: separating chromosomes is difficult. The processes within the cell are quite complex, and there is not enough information on them to allow them to be replicated or imitated in a genetics lab. Neither have there been any simple mechanical solutions to separating chromosomes. Perhaps we are missing the right discovery. By the time asymptotic technology arrives in the genetics area, however, this problem will have been solved.

It's not clear that the ordering of advances and inventions in the genetics grand transformation will make much difference in how an alien civilization will develop. The end result would be the same. But chromosome separation would allow some cost-savings in making genetic changes to organisms, or to the creation of synthetic organisms. If this cost-savings is large, it would emphasize the possibility of having genetically modified or created organisms throughout the civilization.

All we can do now is map the genome of humans and other organisms, and use that information for diagnoses, or in plant and animal breeding. There is some work being done on inserting novel genes into existing plant and animal genomes, but it is very slow. If it were possible to isolate chromosomes rapidly and inexpensively, this would speed up the process. It would also make the process of genetic modification more certain, as a laboratory could simply work with one chromosome and modify it, without having to worry if the modification methodology would accidentally make a modification in another chromosome, with a similar stretch of DNA.

One interesting question to ask is how would an advanced alien society prepare the genetics of their successive generations of their population. Suppose there is an inexpensive way to separate chromosomes. Then, the alien society could simply decide to choose the best set of chromosomes from the copies available. If there is some optimal set, then all the aliens in later generations would be like clones. Alternatively, if the selection was out of the set of a pair of parents (assuming two genders), a wide variety of individuals would remain, but there would be a trend toward more healthy individuals with better capabilities.

Similarly, if there were pairs of parents with some genetic deficiency in one chromosome, specifically in one of the parents, then that chromosome could be eliminated in the resulting next-generation individual. This would result in the gradual elimination of genetic diseases and other problems, although errors in replication remain possible and there would always be a risk of some new mutation arising.

There are many syndromes which arise because of the improper copying of whole chromosomes, meaning extra copies, and with chromosome separation technology, these would be reduced or eliminated as well. Broken chromosomes could be sorted out as well, and mutations arising from copying errors would be detectable and removable. Reading the genome would be less computationally intensive and less prone to mistakes, if each chromosome was read individually. The current Earth method of batching all the chromosomes together and then sorting them out after all the fragments have been read is clearly something that can be improved on.

The technology to separate chromosomes does not seem to be on the horizon, meaning the old methods would be used here for a decade or so. Microbiological investigation into how to make a cell nucleus separate and then how to create microtubules to reach into the mixture and connect to individual chromosomes needs to be done. Once it is well understood how nature accomplishes this task, it would be more reasonable to expect that genetics laboratories can come up with some combination of biological and physical equipment to accomplish chromosome separation. After this, we might see genetics jump forward very fast in potential applications, and this will give us a much clearer idea of what an advanced alien society might be doing with their own technology in this area.

Thursday, March 7, 2019

Later Stages of the Genetic Grand Transformation


In an older post, it was noted that the genetic revolution is likely to be, by a large margin, the most revolutionary of all, in the sense that an alien civilization will be wholly transformed when it happens. The different stages of this grand transformation can be laid out, as they are necessarily sequential. The knowledge gained at one stage is needed for the next stage.

The first stage is very simple, chromosomal selection for embryos. This is extremely old news here on Earth, and there has even been a movie produced about it, entitled GATTACA, from twenty years ago. A couple has twice as many of each chromosome as an embryo needs, so the best two of each type can be chosen. The second stage is what we hear in the news nowadays, which is when specific genes are chosen. Tools for that are just now being found here, and surely in any alien civilization reaching its maturity this would be as routine as antibiotics. Small amounts of changes are what we talk about now, as we don’t have confirmed technology for even that. The technology must exist, however, as inside the cell, genes are moved around during evolution all the time.

Right after that, industrial gestation would be the likely mechanism to be developed next. This particular invention will change an alien civilization more than the Internet has changed out, which is totally. No more parents and no more child-bearing, just new humans. Will parenting become a specialized business, just as has almost every other aspect of life? Why would it be any different? Parenting is extremely rewarding, perhaps more so than any other activity in life, but why not outsource the child-bearing to a machine? Yes, bonding between mother and child will be diminished, and in time, as an alien civilization ages, the role of mother might be also performed by specialists, either trained aliens or some robotics. It is almost trivial to be able to think up problems that might happen with this, but it will be just as trivial for an alien civilization to figure out how to avoid them or turn them into advantages.

Consider for a moment what this point represents. It means that any organism that can be developed in a laboratory can be put through industrial gestation and be ‘born’. This refers to things on alien planets like mammals, but similar processes would be similarly possible for things like plants and insects and whatever else evolved on the planet. In other words, life becomes something like a recipe or a cookbook. AI will undoubtedly be very powerful by the time industrial gestation is well-developed, so the concoction of forms of life which can successfully pass from the egg stage to the real world and on to an adult animal or plant will be quite possible. A huge amount of data will have to be collected, about all the molecules that operate in a living organism, but huge data stores are just the media AI likes to live in.

Now, on Earth, to come up with a new species of plant or animal takes a lot of careful breeding and selection. On a planet with technology a few centuries past ours, it will be done from scratch, without experimentation, as ontology and growth can just be simulated. There can be as many new species as anyone wants to take the time and expense to come up with.

This is by no means the end of the genetic grand transformation. Since reproduction of anything will be economically done industrially, why would there be any species at all? Species are defined as groups of individuals capable of breeding with one another. There would be no need for this, so why have species? There could be a billion clones of some plant if it were desired, or none, meaning that organism was its own species.

Is DNA sacred, or whatever form of organic molecule evolved on an alien planet to serve as the template for genetics? We on Earth are far from knowing how many kinds of molecules can do this job, and if there are more than one, is there another which is more versatile, or more reliable, or easier to work with, or anything else which might mean that the alien technologists would start switching over to it for successive generations of organisms?

And whether DNA or XYZ is used, the legacy method of ontology might be changed. We don’t understand this process very well, but we have observed it in detail. The idea is that each successively evolved species keeps most of the ontology of its predecessor, and adds a little twist to it. Perhaps an alien civilization would rewrite the book, and have a completely different order of development of organs in some new organism they created. Just because something evolved does not mean it was the best that could exist, as there is a barrier posed by the need for evolutionary change to work gradually.

One point made in that earlier post is by the time of these later stages of the genetic grand transformation, it might be reasonable for aliens to switch over from mono-genetic organisms to multi-genetic organisms. We refer to these as chimeras, but that is only a tiny little glimpse of what might be possible. Any optimized genetic package can be used for any organ or part of an organ in a designed chimera. Aliens could choose to use just two or as many as desired. This would mean that an embryo would be fashioned by amalgamating cells of different genetic varieties, all of which were tuned so they could form a cooperative package of cells that could be gestated and have different genetic codes in different parts of the organism.

All the previous stages involve organic biochemistry. At some point, there could be a closer bond between organic and inorganic components in some hybrid object. We on Earth use certain types of microbes to sort out dilute liquids containing minerals, and of course that should be expected to expand far beyond these ideas. For example, technology may well allow communication between whatever passes for neurons on an alien planet, and some semiconductor gizmos of equally small size. The neurons would be tailored genetically for this, and the gizmos specifically designed and printed to be a good substrate. Then anything is possible.

Authors and screenwriters like to play with the idea of a person from some centuries ago being brought into the modern world and being astounded by what they see. Someone from before the genetic grand transformation being brought to a time after it would be immeasurably more confounded by what is seen. We on Earth would do well to simply contemplate these potential changes to better appreciate what an alien civilization of advanced technology really looks like. Then we can better ask the question of why haven’t they visited us here.