Evolution isn't the only scientific theory out there. And if it is ever successfully refuted (in the courts of science, not popular opinion) it won't have been the first theory to fall from grace. Nowadays, scientific theories don't generally crash and burn, but that wasn't always so. One of my favorite examples of a theory that completely died was the Greek "4 elements theory," which hypothesized that everything they could see was constructed of 4 elements and that like attracted like (e.g. drop a stone and it will be attracted to the Earth, which is composed of the same element, more or less).
As my astrophysics professor said in class, this was a legitimate Scientific Theory. It explained past observations and made testable hypotheses.
Which generally proved false.
Hence crashing and burning.
Flash forward and Theories generally get better treatment. Instead of being discarded, they are given a handshake for their notable service to mankind and are allowed to retire to the green pastures of textbooks. For example, when observational evidence demonstrated that Einstein's theories could explain phenomena that Newtonian Physics could not, the New York Times devoted its entire front page to trumpeting the news. But every high school Junior studies Newton all the same. After all, Newton can explain about 99.9% of what a typical High School Student can see (physics-wise).
In my totally uneducated opinion, the difference between the Greeks' 4-elements and Newtonian Physics was the incredible improvement in observations. Newton had far more to explain and therefore his Theory came closer to what any successor was going to have to produce. The Greeks had far less to explain, so wildly different theories could explain the same observations. Evolution has a lot of observations to, by now. So whatever theory eventually replaces it will look a lot like it.
Of course, there are exceptions. For quite some time, our theory of light always involved this concept of the "photon," a little particle that carried light with it. This was a useful model.
You could imagine the sun pumping tons of these little balls of light.
You could imagine them bouncing off of trees.
You could imagine how the process of bouncing off of trees and into your eyes allowed you to see trees.
It explained why you couldn't see the trees
when a blimp passed in front of them,
or when the sun set,
or when you closed your eyes.
Then came the 2 slit experiment and suddenly light wasn't just another particle. It was a wave. After some discussion, we came to realize that light exhibits qualities of particles and waves. It must have been like someone announced that dogs had roots and photosynthesized.
(I am resisting the urge to mention that their bark was still worse than their bite. Whew! That was close.)
Pluto is not earth shattering on that scale. As James Lilek points out (http://www.newhousenews.com/archive/lileks083006.html) Pluto is still Pluto, even as it was before we discovered it. This isn't at all like coming to grips with phloem filled dogs. It's more like deciding that it makes more sense to refer to dogs as aardvarks. Whatever you want to call them, they're still what they were.
So why am I having so much trouble with this?
8,500 soul searching steps today. Cheers,