jar writes:
Yup, both parent species and child species often coexit, at least for awhile.
To use TD's nomenclature: that would be an example of A and B existing.
I think TD is after a parent species, child species and a grandchild species (i.e. A, B and C).
Since parent/child examples are easily found, I expect parent/child/grandchild examples to also exist - but be probably be fewer in number.
But an example currently eludes me.
Edited by Panda, : No reason given.
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