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Extinction as a result of human Activity At one time, a human was just another consumer somewhere in the food chain -just like other animals Human fell prey to predators Human died as a result of disease and accident As human population grew, and as their tools became more advanced, the impact that a single man could have on his surroundings increased tremendously Purposeful use of fire -to change ecosystems Wood was harvested for fuel and building materials Human displaced other kinds of organismsExtinction as a Result of Human Activity • At one time, a human was just another consumer somewhere in the food chain – just like other animals. – Human fell prey to predators. – Human died as a result of disease and accident. • As human population grew, and as their tools became more advanced, the impact that a single man could have on his surroundings increased tremendously. – Purposeful use of fire – to change ecosystems. – Wood was harvested for fuel and building materials. – Human displaced other kinds of organisms
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