In this food web an arrow points from food to its consumer, showing a direction of energy transfer. Grass is a producer using light energy. Grasshoppers, rabbits, frogs and hawks are consumers. A web is a simplified model; it does not include every feeding relationship in nature.
Worked example
Grass -> grasshopper -> frog means the grasshopper eats grass and the frog eats the grasshopper. The arrow does not mean that grass chases a grasshopper around the field.
A Model Meadow
Our model has these four feeding links: grass -> grasshopper; grasshopper -> frog; grass -> rabbit; rabbit -> hawk. Sunlight supplies energy to the grass but is not a feeding link in our count. Fungi and bacteria can break down dead material, returning nutrients to the environment. Energy flows through a web; it does not cycle in the same way nutrients can.