Survival of the fittest

Consider the dandelion.  It puts up a bright yellow flower to attract pollinating bees.  Without pollination, the species would die out in a season. It's an annual plant after all.
  On the other hand, that bright yellow blossom attracts implacable dandelion pluckers like myself.  I like a green lawn, no bare patches.  Each dandelion spreads out and kills a six inch circle of grass around its root.  I have kept a reasonably dandelion free lawn for many years by merely hand plucking every blossom that shows.  With luck I get the root to come up too, so I know that dandelion is really dead.  I don't use weed n feed, 2-4-D, Agent Orange, or other weed killers, fearing they will kill more than weeds.  So that bright yellow blossom can be a liability as well.