Before flowers, the earth was covered with green plants whose reproduction (via pollination) was dependent on the wind. One of the biggest mysteries still today, is when and how (cross pollinating) flowering plants came to dominate the globe.
This means that the flower not only invented sex (by attracting mobile pollinators) but it also developed the first advertising campaign and packaging for its reproductive parts.
Just like the birds and the bees, early humans must have been irresistibly attracted to flowers.
