Are all the animals cows?
Yes, all the animals are cows.
    src        edge_attr  dst
0     0   to the left of    3
1     0   to the left of    4
2     1   to the left of    4
3     1   to the left of    3
4     3  to the right of    0
5     3  to the right of    1
6     3           eating    7
7     3  to the right of    6
8     4  to the right of    6
9     4  to the right of    0
10    4  to the right of    1
11    5       hanging on    8
12    6   to the left of    4
13    6   to the left of    3