A new study identifies nearly 500 minuscule finger and toe bones as belonging to 45-million-year-old tiny primates. Many of the fossils are so small they rival the diminutive size of a mustard seed. Representing nine different taxonomic families of primates and as many as 25 species, the specimens from China include numerous fossils attributed to Eosimias, the very first anthropoid known to date, and three fossils attributed to a new and more advanced anthropoid.