I have been asked by the moderator of this forum to answer this question.
The ability to play darbuka (or as I call it, derbakki) has absolutely NOTHING to do with X or Y chromosomes. It has to do with passion and talent. There are many exceptional darbuka players that are women and the fact that you don't know of any is only evidence that you haven't been around that long or haven't really looked.
I am from America and here there are many. At the very top of my list is West Coast dynamo, Susu Pampenin who is regarded as a scholar of Middle Eastern percussion and belly dance music and has been an inspiration for many (myself included.)You can get a flavor of her playing in the following video. Give it some time. She starts out slow and builds:
Susu Pampenin
A relative newcomer to the darbuka (only last couple of decades) is New York musician, Raquy Danziger (who currently lives in Istanbul) and has gained the admiration and respect of Middle-Eastern musicians worldwide. You can get a flavor of her playing in this video from about 10 or more years ago. She is joined by her friend, Egyptian darbuka master, Osama Farouk as well as the rest of her Raquy and the Cavemen members:
Raquy Danziger with Osama Farouk
Here is a live video from a loud nightclub performance by Sarit Hadad:
Sarit Hadad
These are by no means the extent of great darbuka players that just happen to also be women. There are many and their skills are often exceptional.
As for your comment about small fingers.....I am friendly with the great Arabic musician, Issam Houshan and I call him "The Doumbek Genie" because of his extraordinary ability and skill. His hands are quite small (in fact almost half the size of mine) but his ability and sound that he gets from his derbakki is unsurpassed.
I think that when you wander into the area of associating musical proficiency with gender you are entering unstable ground. You will find that there are more exceptions than there will be "stereotypes." I believe that study, skill and passion is what makes greatness. The only time I ever think about gender is when I am looking for a mate.

Respectfully,
Jeff Webb