▁working ▁in ▁over ▁ 5 0 ▁countries ▁around ▁the ▁world ▁to ▁protect ▁wild life ▁and ▁e cos ystem s . ▁ ▁References ▁▁ ▁Category : American ▁business ▁execut ives ▁Category : American ▁billion aires ▁Category : L iving ▁people ▁Category : 1 9 7 5 ▁birth s <0x0A> </s> ▁In ▁mathematics , ▁the ▁Vol terra ▁lattice , ▁also ▁known ▁as ▁the ▁discrete ▁K d V ▁equation , ▁ ▁the ▁K ac – van ▁Mo er be ke ▁lattice , ▁and ▁the ▁Lang mu ir ▁lattice , ▁is ▁a ▁system ▁of ▁ordinary ▁differential ▁equations ▁with ▁variables ▁indexed ▁by ▁some ▁of ▁the ▁points ▁of ▁a ▁ 1 - dimensional ▁lattice . ▁It ▁was ▁introduced ▁by ▁ ▁and ▁ ▁and ▁is ▁named ▁after ▁V ito ▁Vol terra . ▁The ▁Vol terra ▁lattice ▁is ▁a ▁special ▁case ▁of ▁the ▁generalized ▁Lot ka – Vol terra ▁equation ▁describing ▁pred ator – pre y ▁interactions , ▁for ▁a ▁sequence ▁of ▁species ▁with ▁each ▁species ▁pre ying ▁on ▁the ▁next ▁in ▁the ▁sequence . ▁ ▁The ▁Vol terra ▁lattice ▁also ▁behav es ▁like ▁a ▁discrete ▁version ▁of ▁the ▁K d V ▁equation . ▁ ▁The ▁Vol terra ▁lattice ▁is ▁an ▁integra ble ▁system , ▁and ▁is ▁related ▁to ▁the ▁Tod a ▁lattice . ▁It ▁is ▁also ▁used ▁as ▁a ▁model ▁for ▁Lang mu ir ▁waves ▁in ▁pl as mas . ▁ ▁Definition ▁ ▁The ▁Vol terra ▁lattice ▁is ▁the ▁set ▁of ▁ordinary ▁differential ▁equations ▁for ▁functions ▁an : ▁ ▁an ' ▁= ▁an ( an + 1 ▁– ▁an –