Evolution
“Nothing in biology makes sense except in the light of evolution.” ~ Ukrainian evolutionary biologist Theodosius Dobzhansky in 1973
Biological evolution is descent with modification. Descent is derivation from an ancestor. Descent necessarily refers to a population of organisms, not individuals, for which there can be considerable variance within a population.
The genesis of a new species occurs when a population has a new identity that is somehow distinct from the population from which it came. In the instance of species which practice sexual reproduction, speciation does not necessarily mean that interbreeding with related species terminates. As the wont of sex can be overwhelmingly compelling to creatures, especially males, interspecies randiness is common.
In evolving, the past is not lost. The genetic knowledge that single-celled organisms had acquired were genetically conserved (kept) as multicellular organisms evolved. For many millions of years, gene conservation provides a ready database of consultation for adaptation or other evolutionary impulses of creative design.
“Evolution behaves like a tinkerer.” ~ French biologist François Jacob
The organic nature of biotic evolution means that successful mechanisms are reused and adapted to circumstance. Seemingly new mechanisms always have a heritage.
Sometimes the old ways are the best. Evolution may adaptively revert if that may bring advantage. When considering all the changes involved, what appears as reversion is often instead a transformation.
It may seem self-evident that evolutionary developments are constrained by the energy economics of physics and chemistry, but as life defies entropy, the assumption is unfounded. The most that may be said is that energy economics are often instructive.
As structure facilitates behavior, form fits function in an entangled way. Genetic coding encompasses blueprints that create structures and pathways adapted to intended function.
“Cause and effect are inextricably intertwined in evolution. Feedbacks causally interconnect all factors.” ~ Dutch evolutionary biologist Geerat Vermeij
That environmental circumstance is somehow captured is undeniable. How that transpires will ever be a mystery empirically.
Ultimately, morphology and biological processes are the handmaidens of vital intent. Evolution affords capability, however achieved.
“It is at the level of systems that the guiding hand of evolution is most likely to be evident.” ~ American biomechanist Steven Vogel
Studying evolution invariably involves looking at biological snapshots: comparing one species to another that shares some degree of similarity. The technical ability to examine the molecules that characterize genomes has advanced evolutionary biology in the past few decades. Still, any resultant portrayal is necessarily a sketch.
“Genome evolution, like other evolutionary changes, is opportunistic. Genome evolution is far more complex than straightforward adaptive evolution. Many features may have had a long history in genomes before any benefits to the organism evolved.” ~ English evolutionary biologists Deborah Charlesworth & Brian Charlesworth
However impressive the recent technological progress in studying molecular evidence of evolution’s outcomes, an essential ingredient is left out: the purely energetic aspect. Genetics only evidences evolution: it does not explain it. Evolution amply illustrates that the phenomenal world is deceptive.
Traits are both physical and mental. Just as consciousness cannot be explained by the presence of a brain (and even less so in its absence), DNA cannot adequately account for mental traits. The observable chronicle provided by chemicals is woefully incomplete.
How could a mind be generated from molecules? Hand-waving stories by matterists are laughable. With all the facts known it is easier to prove that what we take for materiality is a mirage than it is to concoct consciousness and mentation from the configurations of atoms – what is, essentially, molecular astrology.
Precocious knowledge is well-documented. There is no reasonable explanation for how complex innate knowledge could be incorporated into certain molecules (nuclei acids) which have been shown to merely relate to manufacturing other chemical compounds (amino acids). Most actions attributed to DNA are conjecture: filling in the gaps between seen molecular substrates and outcomes with stories of cogent energetic processes. For those processes to come about there must be some intelligence behind the molecules. Geneticists do not even understand how genes could possibly produce the morphologies of proteins: the folded shapes which are so crucial to proteinaceous functioning.
“Organisms are the architects of their own selective environments, meaning that behavior and evolution are locked together in a delicate dance. This pas de deux tells us something important about how diversity arises in Nature.” ~ American evolutionary biologist Martha Muñoz
Evolution is adaptation: altering traits in response to environmental conditions. Those conditions include challenges to survival and the aesthetics of living. Some adaptations, notably those related to sexual selection, are sheer statements of beauty, not utility. The art of living is both skill and allure.
“Animals are agents in their own evolution. Birds are beautiful because they are beautiful to themselves.” ~ American ornithologist Richard Prum
No physical substrate shows how adaptation initiates or proceeds. All we can see are some of the results: the physical ones; and observe a smattering of the behaviors which suggest mentation patterns.
Because the coherence which shapes Nature leaves evidence only by its impact on matter (which itself is composed of energy), all we have for historical records are artifacts which can only hint at an obviously intelligent natural force. This leaves our portrait of the elements of evolution tantalizingly incomplete.
“The simple things you see are all complicated.” ~ English musician Pete Townshend in the song “Substitute” (1966)
Analogues and Homologues
“It seems that Nature has taken pleasure in varying the same mechanism in an infinity of different ways.” ~ French philosopher Denis Diderot in 1753
Evolutionary developments that can be traced in lineage are homologues. Similar traits that arise independently are analogues.
Homologues illustrate the incremental nature of evolution. Analogues demonstrate how purpose-driven evolution results in similar adaptations for unrelated organisms. Convergent evolution is the umbrella term for analogues.
Eyes are exemplary of both. As a homologue, monkey and human eyes share a long lineage, with human eyes a modest refinement. By comparison, compound insect eyes are analogues: the same function is achieved, albeit quite differently.
The wings of pterosaurs, birds, and bats differ considerably, yet each is of a forelimb shared by all tetrapods, and so are homologues. Wasp wings are analogues to these.
