This is the food chain in Terraformer as March 30, 2015.
There are 4 trophic levels. Predators can eat animals in the trophic level immediately inferior if their attack points are greater than defense points of the prey. Attack and defense points can be found in each animal adn. At present, Apex predators can not attack herbivores.
Trophic level in Wikipedia:
The trophic level of an organism is the position it occupies in a food chain. The word trophic derives from the Greek τροφή (trophē) referring to food or feeding. A food chain represents a succession of organisms that eat another organism and are, in turn, eaten themselves. The number of steps an organism is from the start of the chain is a measure of its trophic level. Food chains start at trophic level 1 with primary producers such as plants, move to herbivores at level 2, predators at level 3 and typically finish with carnivores or apex predators at level 4 or 5. The path along the chain can form either a one-way flow or a food “web”.