A few thoughts on evolution as a whole:
It is sometimes thought that evolution by way of natural selection happens due to happenstance mutations in genes that happen to offer some adaptive advantage, and are therefore more likely to be passed on to the next generation, thus preserving them through the generations. While this passive collection of traits is part of the evolutionary change process, natural selection is a much larger umbrella of influences, both passive and active, that have the capacity to shape the traits that contribute to an organism’s or ecosystem’s adaptive profile. The various behaviors and structures that ultimately remain coherent within an organism or ecosystem over time are those that enable the local biological field to negotiate the dynamic demands of the environment that they are continuously baptized in while also satisfying the structural hungers that must also be attended to in order to remain coherent. The relational environment contains both nourishing and antagonistic agents and is composed of both organic and inorganic influences that must be dynamically negotiated. This is no small task.
Biology is not just a relationship between organism and environment, it is also a relationship between and among organisms. It is also not solely a passive capture of traits by way of happenstance alone. Once an adaptive trait is “discovered” and embodied by various means, biology also develops various active means to pass the trait along. Biology also arguably searches out these traits and passing them along as well. Our human trait of being explorers in search of opportunity might be one of the ways this active search is facilitated. One illustration of this non genetic kind of trait is the way an animal can develop what are called “Fixed Action Patterns. A squirrel does not have to be told how to store nuts to negotiate the winter. That behavioral repertoire is embodied within the species and passed along through the generations. It was captured and stored at some level which may involve genes, but probably also entails other factors such as epigenetics as well.
Another important distinction to remember in order to see the larger landscape of biological evolution is that evolution is not a process that happens in the context of a species alone. Ecosystems also evolve as a whole body of life and there is a dynamic connection between the organisms within a species in that context. This relationship between organisms also means that organisms convey adaptive traits one to another through various means, both by way of the meaningful structured transmission of information and by way of happenstantial relational communications that confer adaptive traits. These information sources get captured at an organism or ecosystem level and actively spread the same way that the environmental trigger of a mutation in a sperm or egg that confers an advantage is more likely to get passed on.
Organisms exist in the context of many other organisms and this relational environment between organisms adds to the influential factors that shape the evolutionary process as a whole. It is this crucible that includes the deliberate transmission of traits as well as the acquisition of accidental occurrences that leads to the acquisition of adaptive traits that collectively drive the evolutionary process – this process that builds a hedge of coherency against the chaotic forces that would otherwise consume and disintegrate the body of relationships we call an organism, or ecosystem.
There are a number of ways that biological systems communicate adaptive traits one to another. This communication process that enables the passing along of adaptive traits can take the form of cooperative behaviors for instance. When we think about the wealth of adaptive capacities within our species we must consider the debt of gratitude we owe to our ability to share and cooperate. Not one of the words that are being used to communicate this idea for instance, would be understood if it were not for their structure and meaning having been shared with us at some point in time. This cooperative sharing platform has enabled humans to form our civilization.
Words are not the only way traits are transmitted between organisms. Our ability to capture and accumulate knowledge in a verbal net and transmit that knowledge one to another is synonymous with the way nature passes along of meaningful structural traits such as DNA and epigenetic information as well. Among these meaningful structural traits are sounds and behaviors such as postures or ritual sequences of behavior that convey meaning, as well as the passing of influential structures that serve as information one to another. This meaningful structural type of communication can take the form of molecules that we produce and perceive as scents, some of which, like hormones can meaningfully trigger massive behavioral shifts within and between organisms that serve various purposes like reproduction, establishment of adaptive hierarchies of social status, or the avoidance of danger etc. Still other forms of structural communication include the transmission of genetic information within and between organisms. This can happen by way of sexual reproduction, but in some cases can also occur through such methods as viruses, which can stitch genetic segments into already established DNA strands that can subsequently alter the organism in significant ways, some of which offer adaptive advantage.
Here is an article that takes a look at how viruses swap genes with a variety of cellular organisms and become part of that dynamic relational community that produced the fruit of adaptation in some cases.. In other words, viruses are also “agents of [adaptive] diversity” in certain cases: