Ahem, they didn't evolve at all, really, believe me.
The plural form for rabbit ears is (one) rabbit's ears; or (two) rabbits' ears.
True
It's not true that rabbits with long ears have a longer lifespan than rabbits with short ears. Ear length has no bearing on a rabbit's lifespan.
It depends on its species and size. Tiny rabbits have tiny ears.
There are many rabbits with ears sticking up. My Netherland dwarf rabbit, which is the smallest rabbit, has upright ears. Also dutch rabbits and rex rabbits do, to name some. Hope this is of some help :)
All rabbits have long ears...
No. There are breeds who have floppy ears.
Genetics.
Their ears have gotten longer to hear better.
of course silly! :)
Their big ears!
Dessert rabbits along with most dessert mammals have big ears to circulate air through there bodies.