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Most of us hear the word "evolution" and think of the process by which species change and
adapt and maybe turn into other species or go extinct - but that's specifically the evolution
of life forms by means of natural selection. The word "evolution" in general just means
"change or development", and there are plenty of other things that can evolve, or change,
and in plenty of other ways.
For example, the universe can evolve, that is, change, according to the laws of physics
- galaxies form, planets and moons orbit, stars explode, etc. This doesn't mean there's
any sort of cosmic "survival of the fittest" going on - that would be natural selection,
not evolution. Similarly, the demographic makeup of the United States can evolve as
children are born, young people move to cities, immigrants arrive in the country, etc. In
this sense, evolution just means change, and no one can deny that these these changes are
happening - the evidence is overwhelming!
Similarly, around the time Charles Darwin was doing his research, scientists (including
Darwin himself) had begun amassing piles - literally - of evidence that showed that the nature
of life on earth had changed quite significantly over time: our oldest rocks show no signs
of life, while newer and newer rocks reveal fossilized plankton, seaweed, snails, fish,
trees, insects, dinosaurs, mammals, and so on. There absolutely was and is no denying
the fact that life on earth changes - and change over time is what "evolution" means.
What Darwin proposed with his theory of natural selection was an explanation for HOW this
change (which is stupidly well supported by evidence) could have occurred naturally.
You can think of it like the Challenger disaster of 1986: all the evidence showed that the
collection of molecules named "Challenger" had tragically changed/evolved from a space
shuttle and its rocket boosters into a cloud of gas and debris shortly after launch (though
we normally call this kind of evolution "exploding"). The question for scientists at the time was
to understand and explain HOW the explosion had happened so they could prevent it in the
future. Ultimately, it was the Theory of Frozen O-rings in the Rocket Boosters, popularized
by Richard Feynman, that provided a satisfactory explanation for the cause of the disaster.
Now, you're welcome to disagree with Feynman's explanation for the explosion, or Darwin's
explanation for how life on earth changes, but they're pretty darn good explanations
for these incredibly well documented examples of change in the universe.
In the end, the universe will go on evolving regardless of whether you and I believe in
it or understand it, and perhaps the best thing to do is to remember that it's ok for
our beliefs and opinions and understandings to evolve, too. That's part of life, and it's
the way
of science.