488.3 MA
ORDOVICIAN488.3 PERIOD (45.3
M) (488.3-443 MA) Ice Age in
Africa Chordates
appear Graptolites Corals LOWER ORDOVICIAN 488 EPOCH (16.5
M)(488.3-471.8 MA) TREMADOCIAN488
STAGE (9.7
M)
(488.3-478.6 MA) 478.6 MA
FLOIAN478.6
STAGE (6.8
M)
(478.6-471.8
MA)
471.8 MA
MIDDLE ORDOVICIAN471.8 EPOCH
(10.9 M) (471.8-460.9 MA) STAGE
I - MID ORDIVICIAN (3.7
M)
(471.8-468.1 MA)
STAGE 2 - MID
ORDIVICIAN
(7.20)
(468.1-460.9 MA) 460.9 MA UPPER
ORDOVICIAN460.9 EPOCH (17.20) (460.9-443.7 MA) SANDBIAN460.9
STAGE (5.10
M)
(460.9-455.8
MA) 455.8 MA KATIAN455.8
STAGE (10.2
M)
(455.8-445.6
MA) 450 MA Sharks appear? (450-420
MA) 445.6 MA HIMANTIAN445.6
(1.9
M)
(445.6-443.7 MA)