Biological Evolution in a Changing Environment – Towards an Engineering Hypothesis
Many people in the scientific community are questioning Darwin’s theory of evolution by natural selection. No one can dispute Darwin’s contributions to our knowledge of evolution as a phenomenon, but there is increasing skepticism about the theory or process – natural selection – by which evolution is said to take place. The theory of natural selection involves two separate processes, i.e. the mutation process (by which a genetic or, more broadly, a biological mutation takes place) and the selection process (which takes place later, and determines whether the mutated organism survives the challenges of a changing environment). In this case the environment plays a role in the selection process and not the mutation process. Alternative theories of evolution posit that the environment plays a role directly in the process of biological mutation, and as such the selection process is not significant. This would suggest that evolution may be much more rapid than previously thought, particularly in the context of a changing environment.
There is overwhelming evidence that the environment is not simply a limiting factor in the survival of mutated organisms, but rather is a source of extraneous material and energy in the processes that result in mutations in the first place. I will briefly review two such processes before I propose an engineering hypothesis. Horizontal gene transfer, e.g. by means of viruses, is one example of environmental interference in the genomes of organisms. Interestingly, this would entail that all organisms within a species who were infected by a particular virus may mutate at the same time. This is in contradiction with the tree-of-life hypothesis underpinning the theory of natural selection [1]. Secondly, the groundbreaking work of Moshe Szyf and co-workers in the field of epigenetics has shown that environmental contaminants can turn genes ‘on’ or ‘off’ in the mammalian embryo. This study indicates that particular environmental pressures on the systems biology of the embryo can lead to particular hereditary traits [2].
The purpose of this article is to advance an engineering hypothesis of a relationship between environmental conditions and biological mutations. I speculated earlier that the fertilised ovum prior to zygote formation is a possible system for genetic or biological mutations [3]. Within the fertilised ovum the biochemical ‘fusion’ of the male and female pronuclei takes place by means of a biological spindle and energy transfer to/from the environment, leading to the production of the zygote genome. Assuming that the biochemical reactions involved in the fusion process are far-from-equilibrium in relation to the environment, we may be able to apply the chaos theory of the renowned thermodynamicist Ilya Prigogine, as follows.
In engineering terms we can define a biological system as a closed system that interacts with the environment (surroundings) by means of mass transfer (e.g. through a cell membrane) and/or energy transfer (e.g. work done by or on the environment). Prigogine and co-workers proved that in some cases a closed system can exhibit chaotic behaviour when it exists in a far-from-equilibrium state relative to environmental conditions (i.e. when there is a large thermodynamic driving force for mass and/or energy transfer between the system and the environment). Theoretical developments in the field of non-equilibrium thermodynamics reveal that complex, ordered chemical structures can be produced within such systems [4]. It follows that the chemical structure of the zygote genome formed in the fertilised ovum may be dependent upon environmental conditions. Any difference in the environmental conditions would result in altered complexity or composition of the zygote genome.
In summary, it is proposed that the fusion of the male and female pronuclei in the fertilised ovum is a chaotic process in accordance with Ilya Prigogine’s theory. The reordering of parental genes into the zygote genome is sensitive to environmental conditions; any difference in environmental conditions results in altered chemical complexity or composition. This is a natural process of biological mutation in which the environment plays a direct role, unlike Darwin’s theory of natural selection.
