Or search: biology, evolution, phylogeny, speciation, anamorphism, anamorphosis, anthropogeny, macroevolution, microevolution, anthropogenesis
3 Syllables: SUU
Baroness, benefice, benefits, emphasis, Federalists, feminist, menaces, Methodist, Nemesis, prejudice, separates, specialist, terrorist, therapist
4 Syllables: USUU
apprentices, parenthesis, unprejudiced

Found 17 words across 2 groupings. Skipped 2 excess words of a similar stem.