What does the "90" on the figure above indicate?
A)There is 90% certainty that species A₁, A₂, and A3 are a monophyletic clade.
B)The monophyletic clade of species A₁, A₂, and A3 appears as a monophyletic clade in 90% of all bootstrap replicates.
C)Both of the above
D)None of the above

Question

What does the "90" on the figure above indicate?
A)There is 90% certainty that species A₁, A₂, and A3 are a monophyletic clade. 
B)The monophyletic clade of species A₁, A₂, and A3 appears as a monophyletic clade in 90% of all bootstrap replicates. 
C)Both of the above 
D)None of the above

Quizplus · Accepted Answer

The "90" on the figure indicates that the monophyletic clade of species A₁, A₂, and A3 appears as a monophyletic clade in 90% of all bootstrap replicates. This is determined using a statistical method called bootstrapping, which provides a measure of the support for a particular clade based on how frequently it is observed in multiple replicates of the original dataset. Option A is incorrect because the bootstrap analysis only provides an estimate of support for a clade, not a measure of certainty. Option C is partially correct but not the best choice because it implies that both explanations are equally important, when in fact the observation about bootstrap support is the more relevant explanation for the "90." Option D is incorrect because the "90" would not be included on the figure if it had no meaning.

What Does the "90" on the Figure Above Indicate