Not only that--different species have used different parts for the thumb. A Jurassic pterodactyl ("wing-finger") had the earliest known opposable thumb. Pandas have their choice. Primates are late to the party, but might have a claim to most use. Some cats have joined.

The most important key-chord is space, followed by backspace.

Can't forget bats. There's a reason why their order is Chiroptera.

>The name "Chiroptera" derives from Ancient Greek: χείρ – cheir, "hand"[4] and πτερόν – pteron, "wing".[1][5]