Biologists often construct a food network of species in an ecosystem. the vertices represent species, and a directed edge (u, v) means species u eats species v. an apex species is one that is not eate
Biologists frequently erect a help network of sort in an ecosystem. the vertices illustrate sort, and a directed margin (u, v) resources sort u eats sort v. an object sort is one that is not eaten by another sort. think you are confer a schedule of all potential "eating" relationships (so a schedule of "u eats v"). mention all object sort.