As a result, most ecosystems have herbivore food chains that consist of only three or four tropic levels.
(most ecosystems; have; herbivore food chains that consist of only three or four tropic levels) (herbivore food chains; consist; of only three or four tropic levels)
most ecosystems herbivore food chains
have consist
herbivore food chains that consist of only three or four tropic levels
of only three or four tropic levels