What kind of animal is the bird sitting on?
The bird is sitting on the horse.
    src        edge_attr  dst
0     0               of   12
1     0   to the left of    6
2     0   to the left of    1
3     0   to the left of   10
4     0   to the left of   11
5     1               of   12
6     1  to the right of    0
7     1  to the right of    4
8     2           behind   12
9     3   to the left of    4
10    4   to the left of    1
11    4  to the right of    3
12    4   to the left of   11
13    4   to the left of    6
14    5   to the left of   10
15    6   on the back of   12
16    6        riding on   12
17    6  to the right of    0
18    6  to the right of    4
19    6       sitting on   12
20    9   to the left of   10
21   10  to the right of    0
22   10  to the right of    9
23   10  to the right of    5
24   11               of    6
25   11  to the right of    4
26   11  to the right of    0
27   12      in front of    2