Question: What kind of organisms are the most simple to clone?
About the article "Cloning", section "Cloning unicellular organisms".

Candidate passages:
Advances in bioinformatics, refinements of DNA amplification, and the proliferation of computational power have greatly aided the analysis of DNA sequences recovered from environmental samples, allowing the adaptation of shotgun sequencing to metagenomic samples.
The approach, used to sequence many cultured microorganisms and the human genome, randomly shears DNA, sequences many short sequences, and reconstructs them into a consensus sequence.
Shotgun sequencing and screens of clone libraries reveal genes present in environmental samples.
This provides information both on which organisms are present and what metabolic processes are possible in the community.
This can be helpful in understanding the ecology of a community, particularly if multiple samples are compared to each other.
Shotgun metagenomics also is capable of sequencing nearly complete microbial genomes directly from the environment.
Because the collection of DNA from an environment is largely uncontrolled, the most abundant organisms in an environmental sample are most highly represented in the resulting sequence data.
To achieve the high coverage needed to fully resolve the genomes of under-represented community members, large samples, often prohibitively so, are needed.
On the other hand, the random nature of shotgun sequencing ensures that many of these organisms, which would otherwise go unnoticed using traditional culturing techniques, will be represented by at least some small sequence segments. 
These companies are famous examples of the Copy to China model.
Many of them have evolved to more than a simple clone. 
Most levels include a number of interactive contraptions referred to as "traps".
Traps can either alter the landscape, or the clones themselves.
Some of the common traps are:  Teleport - Transports a clone to another part of the level.
Swap (multiplayer only) - Swaps the control and colour of a clone to another group.
Entanglement - Links two clones so that giving a morph to one will result in both clone performing the action.
Squish - Crushes the clone.
Shock - Zaps the clone.
Size - Either double or half the size of the clone.
AntiGrav - Alter the gravity of a clone (4 possible gravities).
Clone Cannon - Blasts a clone to another part of the level.
Speedup - Multiply the speed at which the clone performs morph actions up to 8 times.
Bonus Items - Decorations to alter a clones appearance, stamps to tag the landscape during multiplayer, etc.  
Initially titled "The Clone Wars", the episode's title was later changed to "Attack of Mark's Clone".
Series developer David M. Stern wrote the episode with Adam Stein, and Richard Ferguson-Hull and series creator Devin Clark directed it.
Stein and Mick Kelly served as staff writers.
In an interview with Kevin Fitzpatrick of UGO, Clark spoke of the episode and proclaimed that it was a "really fun opportunity" to see what Mark's clone would be like, calling him an "Agro-Mark".
He said that Matt Oberg, the voice of Mark, voiced the clone as a "much more gruff individual".
Clark elaborated, "It's really funny.
It's like seeing Mark, since we kind of play him so neutered most of the time, it's like seeing him as like this jerk, it's hilarious, it's a very funny story."
Executive producer Daniel Powell said that Clone Mark "glove slaps everyone smokes a cigarette instead of putting it out before the office".
"Attack of Mark's Clone" was the eighth episode to be produced for the second season.
In addition to the regular cast, the episode features appearances by recurring guest voice actors Pete Holmes and Mike O'Gorman.
Comedians Kate McKinnon and Jay Oakerson guest starred in the episode. 
The clarification of the distinction between simple and complex scientific models became in later years a major goal of Rosen's published reports.
Rosen maintained that modeling is at the very essence of science and thought.
His book "Anticipatory Systems" describes, in detail, what he termed the "modeling relation".
He showed the deep differences between a true modeling relation and a simulation, the latter not based on such a modeling relation.
In mathematical biology he is known as the originator of a class of relational models of living organisms, called formula_1-systems that he devised to capture the minimal capabilities that a material system would need in order to be one of the simplest "functional organisms" that are commonly said to be "alive".
In this kind of system, formula_3 stands for the metabolic and formula_4 stands for the 'repair' subsystems of a simple organism, for example active 'repair' RNA molecules.
Thus, his mode for determining or "defining" life in any given system is a functional, not material, mode; although he did consider in his 1970s published reports specific "dynamic realizations" of the simplest formula_1-systems in terms of enzymes (formula_3), RNA (formula_4), and functional, duplicating DNA (his formula_8-mapping).
He went, however, even farther in this direction by claiming that when studying a complex system, one ""can throw away the matter and study the organization order"" to learn those things that are essential to defining in general an entire class of systems.
This has been, however, taken too literally by a few of his former students who have not completely assimilated Robert Rosen's injunction of the need for a theory of "dynamic realizations" of such abstract components in specific molecular form in order to close the modeling loop for the simplest functional organisms (such as, for example, single-cell algae or microorganisms).
He supported this claim (that he actually attributed to Nicolas Rashevsky) based on the fact that living organisms are a class of systems with an extremely wide range of material "ingredients", different structures, different habitats, different modes of living and reproduction, and yet we are somehow able to recognize them all as "living", or functional organisms, without being however "vitalists".
His approach, just like Rashevsky's latest theories of organismic sets, emphasizes biological organization over molecular structure in an attempt to bypass the "structure-functionality relationships" that are important to all experimental biologists, including physiologists.
In contrast, a study of the specific material details of any given organism, or even of a type of organisms, will only tell us about how that type of organism "does it".
Such a study doesn't approach what is common to all functional organisms, i.e.
"life".
Relational approaches to theoretical biology would therefore allow us to study organisms in ways that preserve those essential qualities that we are trying to learn about, and that are common only to "functional" organisms.
Robert Rosen's approach belongs conceptually to what is now known as Functional Biology, as well as Complex Systems Biology, "albeit" in a highly abstract, mathematical form.