i hate to break it like this, it's not a metaphor's worth of sentence that could become a riddle: it's not exactly a - why is a raven like w riting desk? because you're hunched, sitting over it, and scribbling with a pen, like a raven might with its claw(s)?

i wish i could make the following observation into a similar
riddle, but i can't, simply because it's too obvious...
      what bird, could possibly be a far removed cousin
                          of a sparrow?
                                i have two families of sparrows building
nests just outside my window...
                       so i notice the fidget and the "anxiety" of their
little bodies...
                       but the link is in their tails...
  the tails aren't exactly like flowers blooming in spring,
opening like a peacock's tail for courtship...
               nor like the raven's tail... nor like woodland pigeons' tail...
they're sharp, pointy... never unfolding,
           simply because the sparrows are little spitfires...
they require a sharp tail that doesn't unfold, for greater speed,
  like a shark's fin...
                         the natural aerodynamic addition to their little bodies...
so who could possibly be the sparrows' cousin?
             answer?              *magpies!
and because of the longer sharp tail that doesn't unfold,
                                   like the sparrows,
i dare say, i'll call magpies the aero resemblance to the their aqua
       cousins that are, stingrays.
come on... we've differentiated far enough,
        poetry can't differentiate... the "only" thing poetry can
do is integrate... to make language, so dismembered: a whole;
doubly stressed: it's about making associations...
             not about making dissociations...
                         so yeah... sparrows... magpies... stingrays.