<u>Answer:</u>
4. It can decrease dependence on fossil fuels and increase farmers' incomes. Agricultural production of mixed perennial biofuel crops may increase pollinator and avian richness. Most types of agricultural crop-based liquid biofuel production, however, have a negative effect on natural ecosystems and biodiversity.
5. Although agriculture is essential in sustaining human life, the practices associated with it have been known to have certain impacts on the environment. The most notable of these effects includes climate change, deforestation, pollution, and general environmental degradation.
6. Eurasia has more "tropical" animals such as snakes and certain types of birds. Eurasia was blessed with much more mammals that the Americas were in early times and many of the animals in America originated in Asia.
7. People had started growing plants and cattle-herding when they grow tired of moving from one place to another. Hunters and gatherers are nomads. They tend to move when they think that the resources are scarce in their location.They believed that if they could grow these foods instead, they would be able to feed their families and community.
8. What historians say are drawbacks to complex civilizations and agriculture is war, inequality, patriarchy and famine.
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