What clues suggest that the river acts as a "freight train" carrying rock out through the Grand Canyon?

today, in the deepest part of the Grand Canyon, the Colorado River flows past rocks that are 1.7 billion years old,flows, caused the widening of the canyon. Gathering speed and volume, piles of loose rock and soil that originate in a river's tributaries merge to form powerfully erosive debris flows, which are capable of dramatically affecting the surrounding terrain.

Explanation:

his research revealed two genetically different groups of prokaryotes, which justified splitting kingdom monera into two kingdoms. the genetic and cellular differences were so great, that these two kingdoms were eventually placed into different domains in the current three-domain system.

we would need to see the picture to answer it