Grazer

It seems likely that parents are free to respond in these different ways because they have no fear of their child growing into a chronic, adult knee-grazer.

There were large hippolike grazers (Teleoceras, Brachypotherium, and Peraceras superciliosum)[…]

For instance, the little bush moa fed nearly exclusively on forest vegetation, whereas the heavy-footed moa was a grazer in open vegetation habitats.

Grazers have a lower level of involvement and view only when "something is happening."