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The high survival and reproduction rate characterizing the evolutionary history of the homo sapiens

Does Evolution Have a Trajectory? George Mobus One of the first insights I ever thought I had gotten about evolution is that complexity has increased over time. This was at odds with much of conventional wisdom back in the 1960s. Biologists were loathe to characterize evolution as progressive because this smacked of teleology — that evolution was being pushed or pulled in a given direction, presumably by a supernatural power.

The situation wasn't helped by the works of Teilhard de Chardin who, in spite of many valuable insights regarding evolution in general, insisted that the process was unfolding God's plan to create the noosphere.

Of course mainstream biologists gave no credence to this idea; so out with the bath water went the baby. It turns out that the noosphere is a worthwhile observation regarding organization regardless of what it may say about a supernatural power.

GeoChemBio/MetaPrimate/Unique to humans

Today many biologists accept that evolution has followed a general pattern throughout the history of life on Earth. It remains mostly a naturalistic observation about the levels of organization in a hierarchy.

This hierarchy involves increasing levels of complexity that have evolved over time.

  1. Our evolution is guided by the recursive rules of emergence.
  2. Ideas of such essentialism of haplotypes in specific people or peoples creates the same problems as did ideas that certain cranial types were associated with specific peoples in the 19th century, and represented certain behavioral qualities or abilities much to the disgrace of the anatomists who championed those theories [ 110 ].
  3. Ideas of such essentialism of haplotypes in specific people or peoples creates the same problems as did ideas that certain cranial types were associated with specific peoples in the 19th century, and represented certain behavioral qualities or abilities much to the disgrace of the anatomists who championed those theories [ 110 ].
  4. He created a coherent theory of evolution and laid the framework for today's transgenerational epigenetics [ 32 - 34 ].
  5. The Origin of Life The above description is surprisingly general. Imagine a governing body consisting of eusapient beings.

From the origin of life or possibly even before through the first simple, prokaryote cells, through the first eukaryotic cells and up to societies of humans, there is a recursive pattern of aggregating of cooperative individuals molecules to people and an eventual transformation of that aggregate into individuals that interact at a new, higher level of organization complexity. It would be hard to deny that this is a form of progression.

Nevertheless, this new vision of evolution requires explanation that does not depend on teleology. Today, the phenomena of emergence and self-organization are being studied in many different systems contexts. The Future of Evolution I have spent no small amount of time thinking about evolution. And not just the evolution of life in the past.

I also think a lot about the evolution of life in the future. In order to get to a point where thinking about evolution in the future makes sense one has to have discerned something of a pattern of evolution in the past. For much of the scientific history of the study of evolution Darwinian natural selection and chance mutations of genes so-called neo-Darwinism have dominated the generally accepted theories.

The role of chance or random mutation played a heavy part in these theories as the source of novelty and variation upon which then, natural selection could operate to drive speciation. In past blogs I have also written about the theories of Harold Morowitz regarding the flow of energy through local materially isolated systems and how that flow can drive a system toward higher organization. The origins of life on Earth are couched in just such a theoretical framework.

In the systems book I am co-authoring I have been writing about the related phenomena of emergence of organization and something called self-organization.

All of these phenomena now appear to give different perspectives on a universal process that generates increasing organization and levels of complexity so long as energy flows.

Figure 1, below, gives a sense of this progression. Starting at the bottom, under the lower dashed line, we have a materially-closed system comprised of many different kinds of components. The system can be thought of as starting in thermal equilibrium and the components are stable, non-decomposable. The components will be well mixed given a sufficient amount of time passing in this state.

The next level up shows some of the the high survival and reproduction rate characterizing the evolutionary history of the homo sapiens of energy flow, that is when an energy gradient is imposed and the system is driven from equilibrium.

In this case we are mostly interested in components that combine in characteristic ways. Some of its potential for connecting with other components, either of the same or different types, is realized by absorbing energy from the inflow. As can be seen in the figure, some combinations are more complex than others. Not easily seen is that some combinations are more readily made than others due to the connectivity potentials across various types.

Chance plays a large role in determining what combinations actually obtain initially. In the second panel we get a hint at what makes for a stronger association; the entity in the lower right side of the panel has a cyclical connectivity that helps stabilize the association. But local selection forces i.

This makes some components available in the general pool and then the more complex, stable combinations can compete to obtain those to further increase their complexity, and possibly their stability top panel. A combination can be thought to be stable when the mutual linkages between components are strong; in a sense these components are cooperating to keep the bindings stable.

This is in the face of selection pressures that might otherwise dissociate them. By chance, again, some more complex combinations are more capable when it comes to forming stable connections. Evolution toward increasing complexity under the influence of energy flow. A materially closed system consisting of many simple but different components moves upward through successive stages of increasing complexity.

  • The existence of basal tear was discovered only three centuries ago;
  • In recent years claims have been made and controversy produced by the application of DNA analysis in the production of evolutionary trees;
  • But it turns out that some complex entities molecules can actually cooperate with one another in a form of mutualism;
  • The complexity of human societies will be severely diminished in a very short period of time;
  • Here we show an increasing chain of intermediate processes;
  • What are the rules that produce this effect?

Some of these combinations are able to remain viable under the influence of a selective force or forces while others dissociate. As time goes on, with continuing energy availability, the more successful combinations, now acting as unified entities, are able to compete for remaining resources while others are not. Then, depending on the kind of selection forces encountered as a result of this new environment some of the more successful entities obtain resources at the expense of other less fit entities.

The above description of a pattern of increasing complexity can be seen most readily in the realm of chemical evolution such as occurred in the pre-biotic era on Earth.

Much of this can be replicated in laboratory settings where starting with simple molecules in a closed container, and adding various forms of energetic inputs, the system produces a mixture of much more complex molecules, including some of the precursors of life.

However, the above description is more general than just for chemical evolution. The process of individuation and subsequent group formation followed by the evolution of increasing cooperation within the group is a repeating cycle that has been seen in biological evolution at many different levels of organization.

This shows the recursive algorithm-like nature of what is represented in Figure 1. This pattern of progression, with transitions from simple to more complex, repeats itself throughout the biological complexity hierarchy see below. There is a creative tension between cooperation between components forming groups or collections, and competition between different groups.

Moreover, those groups represent new entities at the higher level of complexity. As long as these combinations remain stable under the selective conditions imposed, and under conditions of excess energy availability, they will continue to sweep up free primary components as needed.

There is a limit to this process of incorporation of more components however. As combinations like this get more complex their energy requirements for growth and maintenance also grow. Under conditions of constant energy flow, however, these needs cannot be met and the entities approach an end to growth in complexity and size.

Worse still, from the competing entities' perspectives, if energy flow diminishes over time, then the process reverses and the combinations begin to loose complexity. If the environment changes in substantial ways, this too can cause the entities to fail, their structural and functional integrities to be lost. The Origin of Life The above description is surprisingly general. At first it seems to be slanted toward something like pre-biotic chemical interactions in the primordial soup that gave rise to life.

And, indeed, it does cover that phenomenon. The necessary step to get from pre-biotic evolution to biological evolution is the need for entities to make copies of themselves rather than merely grow in size.

NeoEssentialism, Species, and Molecular Phylogenetics Regarding Hominin Evolution

Moreover, those copies must occasionally be subject to small errors that lead to slight differences in functions behaviors such that the selecting environment may bias further reproduction in the direction of one or more specific version. That biasing is because that version is better fitted to survive in that environment. The step between mere increase in entity complexities, as above, and the beginning of what we might recognize as the first biological-like processes involves the beginning of cooperation between molecular entities.

In Figure 1 I show two entities competing for a component. But it turns out that some complex entities molecules can actually cooperate with one another in a form of mutualism.

These complex entities do not merely have form, they have functions, also determined by the flow of energy.

  1. It uses this model to send adjusting signals to each of the components as needed to achieve the final optimal output. But this is no surprise.
  2. Groups of humans are headed toward the same degree of within-group cooperation as has occurred in so many previous examples. The final process produces a product that is exported to the environment and is likely a factor in the success of this aggregate group in not being selected against, i.
  3. Population of many different components individuals with multiple personalities. These components are linked by some form of attraction or binding and have established flows of material and energy between them as they cooperate.
  4. Claims that certain sequences have evolutionary significance should be considered carefully. Holloway [ 11 ] also pointed out the arbitrary nature of the size of the brain associated with species designation, especially regarding Neandertals.

Most of these entities are not inert, but take in resource components and produce product components under the right energetic conditions. The situation is even clearer in cases where the product output of one entity is a resource input to another entity.

And in cases where there is a chain of these interactions there is a possibility that the output of the final link can act as input to the first, i. This will obtain when the chain acts to funnel energy flow through a sequence of work processes that ultimately give off waste heat at the end, along with components that will be available as inputs for the start of the sequence.

These cycles need not be materially closed. They may form a stable structure due to some of the final outputs being needed as inputs to the start, but they may also operate on other inputs for example smaller entities that contain usable energy and produce usable products by other cycles.

Figure 3A shows a schematic representation of cycle formed when four entities cooperate for their mutual benefits. For an example of a real molecular cycle see: The Citric Acid Cycle in Wikipedia.

Figure 3B shows another necessary step in the emergence of life, the development of an autocatalytic cycle. Autocatalysis has been demonstrated in a number of molecular systems, including and especially in molecules of RNA.

Cycles in which entities cooperate by using resource inputs and the high survival and reproduction rate characterizing the evolutionary history of the homo sapiens usable products in a chain that closes in on itself. Such chains are not strictly materially closed in that they may take in other resources, produced elsewhere, and produce products, not directly used by this cycle. A special kind of cycle occurs when an entity is capable of catalyzing its own generation. This is called autocatalysis and is the prime suspect precursor process for reproduction in living systems.

The key aspect of these cycles is the degree of coupling or connectedness involved to maintain the cycles over long periods of time. As a rule there needs to be some kind of topological constraint on the organization of the individual entities. For example a fatty acid membrane which has a tendency to form naturally when clumps of fatty acids are immersed in water! The point is, of course, that these entities are not competing.

They are cooperating, which is the source of higher-level organization and, hence, complexity. My favorite molecule in the whole world is adenine! The reason is that it is a core molecule in many different chemical entities such as adenosine, the purine nucleoside that is in both DNA and RNA. Adinosine does a spectacular job of linking with amino acids somewhat readily.

  • A special case of modification of function comes when one of the processes in a complex aggregate such as shown, takes on an increasingly important job of helping to regulate the production rates of the various members;
  • Efforts by Hess [ 50 ] and Brothwell [ 51 ] to increase confidence in measurements of variants led to considerations of multiple measurements [ 52 - 55 ];
  • This is particularly strong in efforts to explain the evolution of the "big brain" in hominins and the appearance of language;
  • Humans are not dumb cells;
  • The origin of vasovagal syncope:

In all of the various transfer RNA molecules tRNA adenosine is at the tail end of a cytosine-cytosine-adenosine chain that binds the amino acids. Adenine and some of its derivatives. Black balls are carbon atoms, blue ones are nitrogen, green ones are oxygen, white ones are hydrogen, and orange ones are phosphorus.

Black lines are double covalent bonds, blue lines are single covalent bonds. Adenosine is found in all of the major life chemical cycles in one form or another. Chemical evolution as described here is not really that different from biological evolution in terms of the basic concepts of competition for resources among entities, versus cooperation for mutual benefit.

The former leads to the selection of the most fit entities within the constraints of the environment.