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Re: the tonight show
In a message dated 1/10/01 3:05:40 AM Eastern Standard Time, firstname.lastname@example.org
> > All modern birds are equally closely related to Velociraptor, since they
> > share the same most recent common ancestor. That is, the common ancestor
> > any modern bird and Velociraptor is the same species as the common
> > of any other modern bird and Velociraptor.
> Is this correct? Consider four creatures, A, B, C, and D.
> A --> B --> C
> A --> D
> Both C and D have A as their most recent common ancestor, but because B
> interceded, C may, or may not, be more closely related to A than D.
But George was referring to this situation:
A --> B --> C, E
A --> D
C and E represent modern birds in George's statement, and D represents
_Velociraptor_. C and E are equally closely related to D, since the most
recent common ancestor of C and D is A and the most recent common ancestor of
E and D is also A.