Family-level diversity of four major, ordinal-level, holometabolous lineages. Symbols for ordinal-level lineages: Trichoptera, purple; Coleoptera, blue; Diptera, brown; and Hymenoptera, green. All data were sourced from Labandeira , with updates. The range-through method was used, with data plotted at interval midpoints . The age of Baltic Amber is taken as middle Eocene, discussed in Labandeira ; the geochronology at bottom is after Gradstein et al. . The scale bar designates geologic time, in millions of years. Abbreviations: 1, Pliocene; and 2, Pleistocene + Holocene.