According to the cladogram for the six-kingdom system the Archaebacteria gave rise to the eukaryotes. Theoretically, all six kingdoms have a common ancestor. The first divergence gave rise to the Eubacteria and Archaebacteria. The next major branching gave rise to the ancestors of the four eukaryotic kingdoms.
Because there is insufficient evidence to support the idea that all chimpanzees use tools. the scientist would need lots of hard evidence supporting this conclusion (lots of chimpanzees using tools)
