hubb wrote:Is actually still considered just a theory?
because what is empirical evidence then?
A theory is a framework of knowledge supported by evidence that accounts for known facts. To say things evolve is to say things change over time. This is a fact. Natural selection is the theory that explains how this change occurs. When people say "just a theory" they are typically have the definition of hypothesis in mind. Gravity and germs are also theories. We actually understand a lot more about natural selection than we do about gravity. The empirical evidence comes in a variety of forms from genetic and biochemical to anatomical (including vestigial structures and atavisms) and the geographical distribution of species. The applications of understanding this process has also allowed us to Vaccinate against a variety of diseases which, without knowledge of natural selection, would not be possible. Whats really cool is the laboratory experiments that have demonstrated selection processes in action. My two favorites being Richard Lenski's experiments on bacterial strains and John Endler's experiments on the phenotypic balance between natural and sexual selection achieved by guppies when placed in environments with or without predators present.
As far as the original question goes, I wouldn't say there is an overarching meaning that applies to everyone. Its down to the person to find/construct their own meaning. Passing on genes is all well and good but your genetic contribution is halved for each generation that passes so, while the individual gene is potentially immortal, it doesn't take long for the collection of genes that currently make up who you are to be filtered to a negligible level (the gene is the unit of selection not the individual organism). Compared to just passing on genes, contributing things like ideas, music, literature and the like offer much greater longevity as these things pass through countless generations mostly still in tact and still influence people. I would, for example, see a piece of music that was written hundreds of years ago and still has the ability to move people today as the extended phenotype of that musician that has long outlived their genotype.
