Printer-friendly version THE AGE OF MAMMALS
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Birth To
put things in perspective – age of mammals is in
red (i.e. almost zero on this scale)--------------↓ Of planet 4 (kMy) 3 2 1 now
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Y’rs ago (millions) |
Events |
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‘Epoch’ |
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65+ |
flood
basalts (Deccan Traps) |
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Cretaceous |
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65 |
EXTINCTION (K-T). End of dinosaurs & flying reptiles
Birds |
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period |
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63 |
warm phase starts |
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(throughout period) Mammals and birds take over |
hot |
Paleocene |
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(
“ “ )Plants don’t change much. |
medium |
period |
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60 |
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(65-56
My) |
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56 |
methane outpourings. Surge of global warming |
v. hot |
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55 |
Mammals
take off. Serious primates appear |
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≈54 |
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53 |
Period
of volcanism & high CO2 (soon calms down) |
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50 |
bats
appear |
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(throughout
period) Northern
continents drifting slowly northwards (?) |
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Eocene |
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warm |
Period |
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45 |
(or
earlier)
monkeys (anthropoids) appear |
wet |
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(56-35
My) |
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40 |
Oxygen level falls Planet
starts to cool |
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(gradual |
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Cooling) |
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35 |
Eocene extinction, start of Antarctic ice sheet |
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33 |
Apes
(hominoids) appear (DNA evidence only) |
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30 |
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cool |
Oligocene |
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Period |
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period |
(35-23
My) |
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24 |
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23 |
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20 |
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warmer |
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15 |
further cooling, Antarctic ice sheet
reaches full size |
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Miocene |
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Period |
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gradual |
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(23-5
My) |
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descent |
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10 |
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Into full |
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8 |
grass becomes widespread.
African Rift Valley created |
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7? |
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Ice age |
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6 |
eastern
Med dries up, ‘salinity crisis’, extinctions |
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5? |
HOMINIDS
(early humans) appear |
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4.2 |
BIPEDALS
(A. anamensis) 4.0: Med refills (suddenly) |
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rapid |
Age |
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2.5? |
First
‘Homo’s (getting closer!) |
glacial |
of |
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cycles |
Hominids |
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0 0.2 |
WE
APPEAR (Homo sapiens) |
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©
C B Pease, October 06