Biology — Trophic Cascade

{
  "elements":[
    {"data":{"id":"wolf","label":"Wolves"}},
    {"data":{"id":"deer","label":"Deer"}},
    {"data":{"id":"plant","label":"Vegetation"}},
    {"data":{"id":"bird","label":"Songbirds"}},
    {"data":{"source":"wolf","target":"deer","label":"prey on"}},
    {"data":{"source":"deer","target":"plant","label":"graze"}},
    {"data":{"source":"plant","target":"bird","label":"habitat"}},
    {"data":{"source":"wolf","target":"plant","label":"indirect +"}}
  ],
  "layout":{"name":"breadthfirst","directed":true}
}