Does it actually have any useful purposes or is it some innocuously quirky evolutionary trait?
Speaking Spanish?
WAG. It’s just one of those things. There are a number of such quirks. For example, at a course on “presentation giving” the instructor ask us to fold our hands with interlaced fingers. Then he asked how many had the right thumb on top and how many had the left on top. Most had the right on top but there were a few lefties and it didn’t seem to be related to handedness because he asked about that.
Just one of those things.
It allows you to make a little container for the clitoris without actually touching it during oral/genital stimulation. This is an evolutionary advantage.
Well, it can always get me quite a few invitations if I do it around males. They’re always very disappointed to learn that I have a pronounced gag reflex, though.
Generally I don’t perform my tonguetwirling in public, it tends to give people entirely the wrong idea. However, for the record, I can flip my tongue over to either side. Of the people who can do this, most can only flip it to one side or the other. I can also form a tube with my tongue.
And, guys, I’m married. So don’t bother with the smart remarks.
Having a mobile tongue lets you eat and talk more easily. The toungue has evolved in certain species to do certain tasks (butterflies and hummingbirds have long tongues to drink nectar from flowers; anteaters have long, sticky tongues to trap ants; cows have prehensile tongues to rip up grass) so it’s likely that our tongues are just randomly mutating to keep the gene pool as diverse as possible. Remember also that measurements of human ability always follow the bell curve so there are some people how have “trick” tongues and others with no special skills at all.