The power of accumulation in evolution is common sense!

The Grand Canyon and the "Little Grand Canyon of the Toutle River" at Mt. Saint Helens are both examples of the topic of this thread, the power of successive small changes to accumulate into large effects. The river canyon at Mt. Saint Helens formed gradually over several weeks when a natural dam of the Toutle River gave way and the flow of water eroded through soft ash layers left by the eruption. The river canyon at the Grand Canyon formed over millions of years by the flow of the Colorado River gradually eroding through solid rock layers.You can create similar effects yourself using a simple river modeling technique. Prepare a large sand box with sand treated and packed down in the manner used for beach sculptures. Lift one end of the sandbox a few inches, then use a hose at the high end to introduce a flow of water. If the slope in the sandbox is small and the water flow is small then the resulting "river" will meander. If the slope of the sandbox is greater and the water flow larger then canyons will quickly be cut.Rapidly flowing water filled with debris and gravel can cut quickly through underlying rock like a buzzsaw. A flood overlying a landscape cannot do this. If there had been a global flood a mere 4500 years ago then it would be the dominant geological feature of our planet, but there are no signs of it anywhere.--PercyEdited by Percy, : Added clarification in 1st paragraph.

Hi -Sky-,You seem to be missing the point. The Grand Canyon and Mt. Saint Helens are valid topics in this thread only to the extent that they touch on this thread's topic, which is how small changes can over time create large effects. This is what happens in geology, and this is what happens in evolution.It's not really relevant to the topic that you don't believe the Grand Canyon formed gradually. If the Grand Canyon is not a good example for you of small changes accumulating over time then there are many other examples we can supply to make clear the way evolution works. But you did make a couple errors that are worth correcting just for purposes of creating an accurate record in this thread. You can't have the flood both deposit and erode the same sedimentary layers, and as mentioned earlier, a flood cannot carve canyons in the landscape it covers. That takes the focused flow of a river. Dr. Elston believes the Grand Canyon is even older, millions and millions of years older, than mainstream geology, and that it was formed by rivers even more ancient than the Colorado, not by a global flood a mere 4500 years ago. You're citing in support of your position someone who disagrees with you even more than mainstream geology.Your many short posts and frequent errors indicate that you're not taking sufficient time and care. At EvC Forum you're expected to support your position yourself, not ask those who disagree with you to do it for you. This is from the Forum Guidelines:

4. Points should be supported with evidence and/or reasoned argumentation. Address rebuttals through the introduction of additional evidence or by enlarging upon the argument. Do not repeat previous points without further elaboration. Avoid bare assertions.

--PercyEdited by Percy, : Grammar.

This topic evolved into one that could have been called The Present is the Key to the Past. The same processes we see taking place today, such as erosion and the slow accumulation of sediments in oceans, lakes and river mouths, are the same ones that shaped our planet in the past. And of course there are also rapid processes, such as hurricanes, earthquakes, volcanic eruptions, tsunamis and asteroid strikes, though these are inconstant and unpredictable.In this way evolution is analogous to geology. For the most part evolution is the accumulation over time of tiny changes, though occasional larger changes like gene or chromosome duplication can also occur. There's even the equivalent of asteroid strikes when a segment of virus DNA becomes inserted in an organism's own DNA.All these processes, both geological and evolutionary, leave evidence behind. Things that actually happened in the past leaves traces of the fact that they actually happened.--Percy