Researchers found that the combination of human encroachment with the warming contributed to the extinctions.
People had trouble trying to wrap their minds around how the Passenger Pigeon could disappear,. They came up with all kinds of theories to explain why it wasn’t human’s fault, like that the birds moved to South America and changed their appearance. There is a similar reaction now. There is a common human reaction that when confronted with an inconvenient truth to deny it, You can see it today with climate change.
A mass extinction caused by volcanic activity wiped out some of the dinosaurs' competitors, allowing them to assume ascendancy. Of course, another mass extinction, caused by a meteor impact caused their demise. Earth is not as hospitable to life as we might like to think.
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