What kind of animal is the water behind of?
The water is behind the elephants.
    src        edge_attr  dst
0     0    standing near   15
1     0             near   15
2     0      in front of   15
3     0               by   15
4     1   to the left of   13
5     1   to the left of    3
6     2   to the left of    5
7     3  to the right of    1
8     5   to the left of    7
9     5  to the right of    2
10    7  to the right of    5
11    7  to the right of   11
12   10               on    5
13   11   to the left of    7
14   13  to the right of    1
15   13             near   15
16   15           behind    0
17   15             near    0
18   15             near   13