PBA 1: Environmental Change Timeline

By davinamagofna

  • The Industrial Revolution

    The Industrial Revolution
    In the middle of the 1700s
    1. Energy sources shifted from animal muscle and running water to fossil fuels, such as coal and oil.
    2. The light bulb was invented and greatly improved the quality of life.
    3. In the 1900s, modern societies began to use artificial substances in place of raw animal and plant products.

  • The Hunter-Gatherers Period

    The Hunter-Gatherers Period
    8,000 - 7,000 B.C.
    1. Humans migrated from place to place as different types of food became available at different times of the year.
    2. Some 80,000 to 70,000 years ago, some hunter-gatherers groups began to specialize, concentrating on hunting a smaller selection of game and gathering a smaller selection of food.
    3. This specialization of work also involved creating specialized tools, such as fishing nets and hooks and bone harpoons which set the stage for agriculture.

  • The Agricultural Revolution

    The Agricultural Revolution
    5,000 - 4,000 B.C.
    1. The agricultural revolution allowed human populations to grow at an unprecedented rate. As populations grew, they began to concentrate in smaller areas which increased pressure on local environments.
    2. The agricultural revolution also changed the food we eat.
    3. Agriculture brought deep social divisions and inequality between the sexes.

  • The 21st Century

    The 21st Century
    Now
    1. We are producing wastes faser than they can be disposed of.
    2. Resources are being depleted.
    3. We are losing species.