Malaria is a widespread disease in tropical Africa. A study looked at the outbreaks of malaria and annual rainfall patterns over a period of 30 years in an area of Western Kenya where many families live and work on tea estates in the highlands.

The graphs show the seasonal patterns of malaria and rainfall at a tea estate in Western Kenya. In both graphs the vertical bars correspond to one standard deviation above and below the mean.

The food conversion ratio (FCR) is the ratio between the mass of food given to a farmed animal and its corresponding increase in mass. The first bar chart shows the FCR for four farmed animals. The second bar chart shows the percentage yield of edible meat provided by each whole animal.

Three groups of human volunteers were given different amounts of almond nuts added to a controlled diet for a period of 68 days. During that period the amount of energy released in their feces was measured.

The graph is a model showing biomass and respiration levels in a field where farming stops at time zero and the abandoned land develops into forest.