Final answer:
A mountain range that separates the driest and wettest places is an illustration of the rain shadow effect, such as with the Cascade Range in the western U.S. and highlands of Ethiopia that create distinct climates on their respective leeward sides.
Step-by-step explanation:
When considering the mountain range that separates the driest and wettest places, we are addressing the concept known as the rain shadow effect. This occurs when moist air from the ocean rises over a mountain range, leading to rainfall on the windward side while the leeward side receives little to no precipitation due to the drying of air. One prominent example of this is the Cascade Range, which influences the climate of the western United States by creating wet conditions on the windward side and arid conditions in regions like the Great Plains.
The highlands of Ethiopia also produce a similar effect, where high elevations restrict precipitation to the east, transforming the environment from tropical to savanna-like with conditions of sparse forests and open grasslands. In general, depending on the geographic location of mountain ranges, there can be significant differences in the amount of precipitation on either side, leading to variance in climate and vegetation.