Figure 3. Same as Fig. 1 but we have removed the three lineages (dolphins, birds and ungulates/carnivores) with increasing E.Q. after diverging from our lineage. The lineage that leads to us provides no evidence of a generic trend towards increasing E.Q. because it has been selected to have that property. Notice that all of the increase in E.Q. is on the lineage that leads to humans. After diverging from us, all lineages shown here (lower vertebrates, archaic mammals, insectivores, prosimians, monkeys and apes) stayed at approximately the same E.Q. The lineages that remain flat represent the vast majority of all the species that evolved from the low E.Q. group shown in the lower left at 200 million years ago. The stasis of the E.Q. of the vast majority of species is evidence for an absence of selection pressure towards higher E.Q. The lineages whose E.Q. did increase after diverging from our lineage (dolphins, birds and ungulates/carnivores) are discussed in "Interpretational Problem #3."
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