Letters to the editor
From the issue of March 23, 2013
By Science News
Grand Canyon rising
If the geology of the Grand Canyon dates back to 70 million years ago “Grand Canyon’s age pushed back,” (SN: 1/12/13, p. 15), that would be around the same time the Rocky Mountains were being pushed up by the subduction process originating off the western continental coast. Could the lifting of the Colorado Plateau be related to the lifting of the Colorado Rockies?
Joe Flynn, Spanaway, Wash.
The timing of the Colorado Plateau’s uplift remains fairly controversial, including whether it occurred all at once or in several discrete stages. But many geologists think it may have been at least partially related to the same event (known as the Laramide orogeny) that raised the Rocky Mountains between about 70 million and 40 million years ago. — Alexandra Witze
Seeing clearly
Regarding your article on the surge of nearsightedness “Urban Eyes,” (SN: 2/9/13, p. 22): When my mother taught third grade in the early 1930s, teachers were instructed to have their students stop their work on a regular basis and look out the large bank of windows on the north to the distant mountains. She often said that there is nothing new in education; the experts just rediscover the old.
Carolyn Conner, Chula Vista, Calif.
As a teenager in the ’60s, I saw an article on submarines mentioning that men on sub duty become nearsighted (irreversibly, it was thought). The thinking was that living weeks at a time with nothing more than six feet away was to blame.
Simon G. LePorte, Hanson, Mass.