195 54 Triassic Diversific- ation of conifers and ferns 225 30 Paleozoic Permian Rise of
Coniferales 280 55 Car- Expansion of boniferous ferns, (Pennsyl- lycopods and vanian) calamites 325 45 Car- 345 20 boniferous (Missi- ssippian) Devonian Major vascular plant groups (including protogymnosp- erms) except angiosperms present 395 50 Silurian Simple vascular plants appear 435 40 Ordovician First Vertebrates 500 Cambrian Algae 590 Precambrian Unicellular eukayotic algae at end of era 4600 65 Table 2.