Sample 4
deer → 1
elk → 1
blackbuck → 1
pony → 2
mule → 2
male-horse → 2
warhorse → 3
goat → 4
sheep → 5
bison → 6
zebra → 7
2 → 3
3 → 4
4 → 5
5 → 6
6 → 7
1 → 2
1
2
3
4
5
6
7
deer
elk
blackbuck
pony
mule
male-horse
warhorse
goat
sheep
bison
zebra