Artificial life (a-life, from artificial life) is the study of life , living systems and their evolution with the help of man- made models and devices. This area of ​​science studies the mechanism of processes inherent in all living systems, regardless of their nature. Although the term is most often applied to computer simulations of life processes, it also applies to wet alife and the study of artificially created proteins and other molecules. For simplicity, this article describes computer life.

Review

Artificial life deals with the evolution of agents or populations of organisms that exist only in the form of computer models in artificial conditions. The goal is to study evolution in the real world and the possibility of influencing its course, for example, in order to eliminate some hereditary restrictions. Model organisms also allow previously impossible experiments (such as comparing Lamarckian evolution and natural selection ).

Philosophy

Currently, the widely accepted definition of life does not allow computer models to be considered living. However, there are other definitions and concepts:

• The concept of strong artificial life (English  strong alife) defines “life as a process that can be abstracted from any specific medium” (John von Neumann).
• The concept of weak artificial life (English:  weak alife) denies the possibility of creating life separately from its chemical carrier. Scientists working within this concept are trying to understand the basic processes of life, not imitate it.

Technologies

• Cellular automata are often used to model life, especially due to their ease of scaling and parallelization. Cellular automata and artificial life are historically closely related.
• Neural networks - sometimes used to model the intelligence of agents. Although traditionally a technology closer to the creation of artificial intelligence, neural networks can be useful for modeling population dynamics or highly evolved self-learning organisms. The symbiosis between learning and evolution is a central concern of theories about the development of instincts in higher organisms, such as the Baldwin effect.

Evolution

In artificial life modeling systems, Lamarckism in combination with “genetic memory” is quite often used to accelerate the evolution of innate behavior, for this purpose all the memory of the simulated individual is transferred to its offspring. Moreover, unlike classical genetic memory, only the memory of the previous generation is transmitted to the offspring. In doing so, Lamarckism can be combined with Darwinism, which can be used to model other aspects of model organisms.

Artificial Intelligence

Traditionally, the creation of artificial intelligence uses structure-to-element design, while artificial life is synthesized using element-to-structure design.

Artificial chemistry

Artificial chemistry began as a set of methods by which chemical processes between elements of artificial life populations are modeled. One of the most convenient for studying objects of this kind is the Butlerov reaction - the autocatalytic synthesis of carbohydrates from an aqueous solution of formaldehyde in the presence of calcium or magnesium hydroxides:

x CH₂O => C_xH_2xO_x

As a result of the reaction, a mixture of carbohydrates of very different structures is formed. If the amount of formaldehyde (“nutrient medium”) in the solution is limited, a kind of equilibrium is established in the system between the processes of growth and decay of carbohydrate molecules. In this case, as in biological systems, the strongest survive, that is, a kind of “natural selection” occurs, and the most stable (under given specific conditions) carbohydrate molecules accumulate in the system.

It is believed that similar processes that took place in the prebiological chemistry of the Earth led to the emergence of life on the planet.

Evolutionary algorithms for optimization problems

Many optimization algorithms are closely related to the concept of weak artificial life. The main difference between them is how the agent's ability to solve a problem is determined.

• Ant algorithm
• Evolutionary algorithms
• Genetic algorithms
• Genetic programming
• Crowd Intelligence ( Swarm Intelligence )

Evolutionary art

Evolutionary art uses technology and artificial life techniques to create new types of visual art. Evolutionary music uses similar technologies, but applied to music.

Mycoplasma laboratorium  - artificial life project

Mycoplasma laboratorium  is a species of bacteria of the genus Mycoplasma , a planned, partially synthetic species of bacterium derived from the genome of Mycoplasma genitalium . This work is being carried out at the J. Craig Venter Institute by a team of about twenty scientists led by Nobel laureate Hamilton Smith, including DNA researcher Craig Venter and microbiologist Clyde A. Hutchison III.

The team began with the bacterium Mycoplasma genitalium , an obligate intracellular parasite whose genome consists of 482 genes spanning 580,000 base pairs arranged on a single circular chromosome (the smallest genome of any known natural organism that can be grown in free culture). They then systematically removed genes to find the minimum set of 382 genes that are capable of life. This work was also known as the Minimal Genome Project .

The team intends to synthesize the chromosome DNA sequences consisting of these 382 genes. Once the 381-gene version of the minimal chromosome was synthesized, it was transplanted into a Mycoplasma genitalium cell to create Mycoplasma laboratorium .

The resulting bacterium , Mycoplasma laboratorium , is expected to be able to copy itself with its artificial DNA, so it is the only synthetic organism to date, although the molecular machine and chemical environment that would allow it to copy are not synthetic.

In 2003, the team demonstrated a rapid method for synthesizing a genome from scratch, producing the 5,386-base genome of the bacteriophage Phi X 174 in about two weeks. However, the genome of Mycoplasma laboratorium is approximately 50 times larger. In January 2008, the team reported to synthesize the full 580,000 base pairs of the Mycoplasma genitalium chromosome , with small modifications so that it is not infectious and can be distinguished from the wild type. They named this genome Mycoplasma genitalium JCVI-1.0 . The team also demonstrated the process of transplanting a (non-synthetic) genome from one species of Mycoplasma to another in June 2007. In 2010 they showed that they were able to synthesize 1,000,000 base pairs of the Mycoplasma mycoides genome from scratch and transplant it into a Mycoplasma capricolum cell ; after this, the new genome was integrated into the cell, and the new organism became able to reproduce.

The J. Craig Venter Institute filed patents for the Mycoplasma laboratorium genome ("minimal bacterial genome") in the US and internationally in 2006. This expansion of the field of biological patents is being challenged by the watchdog organization Action Group on Erosion, Technology and Concentration.

Venter hopes to eventually synthesize bacteria to produce hydrogen and biofuels , and also absorb carbon dioxide and other greenhouse gases. George Church, another pioneer in synthetic biology, believes that Escherichia coli is a more efficient organism than Mycoplasma genitalium , and that creating a completely synthetic genome is unnecessary and too expensive for such tasks; he points out that synthetic genes have already been incorporated into Escherichia coli to accomplish some of the above tasks.

OpenWorm

OpenWorm  is an international project to create a computer model ( in silico ) at the cellular level of one of the most fully studied microorganisms by modern biology - the worm Caenorhabditis elegans.

The project's ultimate goal is a complete model that includes all of the C. elegans cells (just under a thousand). At the first stage, the movement of the worm will be simulated, for which the work of 302 nerve cells and 95 muscle cells will be simulated. As of 2014, models of the neural connectome and muscle cells have been created. A three-dimensional interactive anatomical atlas of the worm is available on the project website. Participants in the OpenWorm project are also developing the geppetto platform, designed for modeling entire organisms.

In 2015, project coordinator S. Larson stated that the set goals were achieved by 20-30%.

Gray slime

Gray goo is a hypothetical doomsday scenario associated with the success of molecular nanotechnology and predicting that uncontrolled self-replicating nanorobots will consume all of the Earth's biomass , carrying out their self-reproduction program (this scenario is known as “ecophagy”).

Typically, the term is used in the popular press or science fiction. In the worst-case scenarios postulated, requiring large, space-capable machines, matter outside the Earth also turns into gray goo. This term refers to a large mass of self-replicating nanomachines that have no structure on a large scale, which may or may not turn out to be like goo. Disaster occurs due to the deliberate activation of the Doomsday Machine or from accidental mutation in self-replicating nanomachines used for other purposes, but designed to operate in the natural environment.

Digital organism

A digital organism is a self-replicating computer program that mutates and evolves. Digital organisms are used as a tool to study the dynamics of Darwinian evolution , to test or verify specific hypotheses or mathematical models of evolution. These studies are closely related to the field of creating artificial life.

Self-replicating machines

Self-replicating machines (SMs) are a type of autonomous robots that are capable of self-replicating themselves using materials from the environment. Thus, SMs are in some ways analogous to living organisms. The concept of SM itself was proposed and tested by Homer Jacobsen, Edward Forest Moore, Freeman Diteson, John von Neumann and later by Eric Drexler in his book on nanotechnology, machines of Creation: The Coming Era of Nanotechnology, and by Robert Fratos and Ralph Merkle in their book. Kinematics of Self-Replicating Machines”, which provided the first comprehensive analysis of a whole variety of SM designs.

Criticism

The history of artificial life has seen quite a lot of controversy and controversy. John Maynard Smith criticized some work on artificial life in 1995, calling it “fact -free science”. However, recent publications on artificial life in major scientific journals such as Science and Nature indicate that the technologies used to simulate artificial life are accepted by the scientific community, at least for the study of evolution.