Re:Not convinced (Score 3, Informative)

There's a book mostly intended as a resource for sf writers, What if the Moon didn't Exist? , which details many of the poor consequences for creatures like us given the absence of a large moon for earth. Its been years, but I remember two of the big ones.

First, without tidal interaction with a large moon, the earth would spin a great deal faster on its axis, resulting in much stronger and consistent winds. It would be hard for anything to be more than a few inches tall except in the windshadow of tall mountains, which themselves would erode much faster.

Second, without the tides, the transition from ocean life to land life would have been much more difficult, since there would be nothing like tidal pools to serve as temporary havens and opportunities for the creatures making that transition.