What does 'every dog has its day' mean?

Reread paragraph 4. what direct impact did the efforts individuals like ava deer have?

Unit testactivelike sparkling stars strewn across the night sky.their brilliance catching the corner of my eye,making me slow down, just to look at them a little longer.in my awe of the sheer beauty of merely broken glass,i couldn't but thinkhow someone else's tragedycould be so beautiful to me.source: t., jennifer. "irony." teen ink. teen ink, n.d. web. cjuly 2011.the poem is an example ofexternal conflictinternal conflictdramatic ironysituational ironymark this and returnsave and exitsubmit

The difference between the present reservoir, with its silent sterile shores and debris-choked side canyons, and the original glen canyon, is the difference between death and life. glen canyon was alive. lake powell is a graveyard. which word best contributes to the author’s sad tone?