Answer:
1) Europe during the late middle ages, the reason was the Black Plague, a disease that came from the fleas of rats, and that was very contagious. It killed about one third of the european population of the time. Some cities like Genoa in Italy lost about 70% of their population.
2) Physiological needs such as food, shelter, water
3) Population growth, poverty and the need for economic growth, pollution, overexploitation and depletion of natural resources, erosion, desertification.
4) Is the maximum amount of species, including humans, that an econsystem can sustain. For example, the carrying capacity of a desert is much lower than the carrying capacity of the Amazon.
5) Ecological deficit occurs when the footprint of a population is higher than the carrying capacity of the ecosystem. For example, according to the footprintnetwork, a science organization that measures the ecological deficit, in the United States, the carrying capacity way lower than the footprint of the average american, therefore, in the United States there is a big ecological deficit.
6) Eat less meat, cows emit methane which is very harmful to the enviroment and contributes to climate change. Eat food that is produced locally, this in order to avoid emissions from transportation of resources. Save water. Do not take hour-long showers or baths. Do not powerwash your house everyweek.
7) The Green Revolution, which started in the mid XX century, has saved billions of people from starvation. It consists on a series of improvements in crop irrigiation, seed selection, and use of fertilizers and pesticides. It also promotes the use of GMO foods. Many people oppose the green revolution for these reasons, but the facts show that while it's not perfect, it has reduced world hunger by a great margin.
