“Actually the mechanics of both answers are basically the same: because that is the most efficient design for a wide variety of front limbs.”
Bats are have more efficient ‘wings’ than birds. Why did birds get feathers and bats not?
“Bats are have more efficient ‘wings’ than birds.”
Umm, bats are gliders and birds are true fliers, so you can’t make a direct comparison of the efficiency of design, as the wings are designed for different purposes.
I’ll have to ask the Designer about that. Might take a few eons for me to get around to it, though. If you’re really interested, you might try to figure out how to make sure you’re on friendly terms before you meet Him, and thus afford yourself the opportunity to pose the question on your own behalf.
Besides which, if you’re not on friendly terms with Him, I won’t be able to communicate His answer to you once I get it.
So for that and other reasons, please get to know Him yourself. He’s really a nice Person and wants to be your friend, but he won’t force Himself on you.