What kind of animal are the trees in front of?
The trees are in front of the zebras.
    src        edge_attr  dst
0     0  to the right of    7
1     0  to the right of    6
2     0  to the right of    1
3     1   to the left of    0
4     1           behind    8
5     1           beside    0
6     1   to the left of   10
7     2               of    1
8     3               of    8
9     3  to the right of   12
10    3  to the right of    7
11    4  to the right of    9
12    6   to the left of    0
13    7   to the left of    0
14    7   to the left of    3
15    7   to the left of   12
16    8           behind   10
17    8      in front of    1
18    9   to the left of    4
19   10  to the right of    1
20   10      in front of    8
21   12   to the left of    3
22   12  to the right of    7