species_1 + species_25 -> species_0
species_0 -> species_1 + species_25
species_3 -> species_2
species_2 -> species_3
species_5 -> species_4
species_4 -> species_5
species_7 -> species_6
species_6 -> species_7
species_9 -> species_8
species_8 -> species_9
species_11 -> species_10
species_10 -> species_11
species_13 -> species_12
species_12 -> species_13
species_2 -> species_3
species_15 -> species_14
species_15 -> species_14
species_14 -> species_15
species_17 -> species_16
species_16 -> species_17
species_6 -> species_7
species_0 -> species_18
species_20 -> species_19
species_19 -> species_20
species_22 -> species_21
species_21 -> species_22
species_24 -> species_23
species_23 -> species_24
species_9 -> species_8
species_30 -> species_1
species_1 -> species_18
species_24 -> species_23