An ecological network contains biotic and abiotic nodes and links between these nodes, an ecological node may represent an individual plant or animal, a whole population or species. Interactions between them can take many forms, but are generally divided into antagonistic trophic interactions, what are called food webs with interactions such as that between predator and prey, or mutualistic symbiotic interactions such as that between pollinator insect and flowering plant. Network structure describes patterns and structures within the overall ecological network.