What is the Hyperdisease Hypothesis?

The hyperdisease hypothesis was developed by Ross MacPhee (American Museum of Natural History) and Preston Marx (Aaron Diamond AIDS Research Center and Tulane University). They argue that highly infectious, contagious diseases caused by microbes played the leading role in causing megafaunal extinctions in North America and probably on many islands. As will be explained in succeeding paragraphs, "hyperdiseases" are not a different class of diseases but, instead, ones that have managed to jump across a species boundary, with highly lethal effect.


What is the Hyperdisease Hypothesis?
How did Hyperdisease cause extinctions?
What is the evidence for the Hyperdisease Hypothesis?
Can the Hyperdisease Hypothesis be falsified?