There is a reason that most couples today do not have a significant age difference. Consider that over the last one hundred years, the average age difference between married couples is 3.5 years.
The Colorado River flows from the Continental Divide in Colorado's Rocky Mountain National Park into the Gulf of California between the Baja California peninsula and mainland Mexico. Here, Snowmass Mountain looms above the Roaring Fork River, a tributary of the Colorado. Peter McBride.
This species formerly occurred throughout much of the Colorado River basin, from western Colorado and southwestern Wyoming to northern Arizona (and perhaps California), including not only the Colorado River, but also major tributary systems such as the Green River, lower Yampa River, and White River (Utah).