Why do some scientists propose the Anthropocene Epoch should begin with the widespread adoption of Watt's engine?

Answer

Massive-scale exploitation of fossil fuels.

Many scientists argue that the changes unleashed by Watt, specifically the massive-scale exploitation of fossil fuels made viable by his efficient engine, have begun to alter the physical makeup of the planet.

Why do some scientists propose the Anthropocene Epoch should begin with the widespread adoption of Watt's engine?
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