SYSTEMATIC BIOLOGY RETURN TO THE KINGDOM VIRIDIPLANTAE
HOME SYLLABUS WEEKLY ASSIGNMENTS J. SYSTEMATIC BIOLOGY TAXA OF LIFE

THE GEOLOGICAL TIME SCALE

EON

ERA

PERIOD

MARGULIS & SCHWARTZ (1998)

BOLD, ET AL. (1987)

PHANEROZOIC

CENOZOIC

QUATERNARY

0-2.5

0-2.5

TERTIARY

2.5-66

2.5-65

MESOZOIC

CRETACEOUS

66-144

65-136

JURASSIC

144-213

136-190

TRIASSIC

213-238

190-225

PALEOZOIC

PERMIAN

248-286

225-280

PENNSYLVANIAN

286-360

280-325

MISSISSIPPIAN

325-345

DEVONIAN

360-408

345-395

SILURIAN

408-438

395-430

ORDOVICIAN

438-505

430-500

CAMBRIAN

505-590

500-570

PROTEROZOIC

VENDIAN

520-700

570-3100

RIPHEAN

700-1800

APHEBIAN

1800-2600

ARCHEAN

2600-3900

HADEAN

3900-5000

3100-4700

Geologic time scale and approximate dates for the respective time intervals as given in Margulis & Schwartz (1998) and Bold, et al. (1987). Dates are in millions of years.