Recent content by ErikDPhillips

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    An astronomer calculated that Earth's intelligent life is probably 'rare.' Here's what that means.

    John, I found a source to back you up... "The amount of CO2 in the atmosphere was reduced by about 90% during the last 150 million years. If this trend continues CO2 will inevitably fall to levels that threaten the survival of plants, which require a minimum of 150 ppm to survive" -...