To fly, or not to fly?

Two articles talk about taking flight today:
First, yet another theory on how dinosaurs might have evolved wings and ended up at our birdfeeders. This one involves trying to go uphill a bit faster.
And challanging the idea that something as complex as flight doesn't 're-evolve' after a creature evolved away from its use is a story of the indecisive stick insect. DNA testing implies that it can't decide if it wants wings or not, evolving them, then evolving them away, 4 or 5 times, over the millions of years of the insect's evolution.
Both were recently published in Science.