Discuss the indicator of food production and the ability to feed the population. Elicit the 3 main grains used to supply more than 1/2 the calories consumed.
Discuss how world grain production has increased since the 1950's through the use of expanded irrigation techniques, fertilizer production, and new genetic varieties of food plants, which demonstrate genetic variation.
Discuss how even with all the technology, production is leveling off. View line graph of production and population growth.
Discuss the difference between inorganic fertilizer which is produced in chemical factories, and organic fertilizer derived from manure and composting. Relate how the particle size differs, with the smaller molecular sized inorganic fertilizers more easily seeping through the soil into ground water, causing pollution.
Review average global temperature changes, with the planet heating up.
Discuss the effects of greenhouse gas increases in the atmosphere and the anthropogenic causes.