Here I test four predictions of the coupled logistic model.
Most groups exhibit nonrandom evolutionary dynamics over long periods of time.
Nonrandom replacement is spurred by major mass extinctions because this speeds up the coupled logistic dynamics. During long periods of replacement of one EF by another, both EFs will show nonrandom dynamics. I quantify nonrandom dynamics using a simple G-test. The test compares observed and predicted counts of origination and extinction events within each group in a time slice. Curves may be computed separately for each group to test these ideas.