1.7
24
34
Cainozoic Era
8
55
65
Marsupials
Placentals
Cretaceous
100
Amphibians
141
Mesozoic Era
Mammals
Jurassic
Birds
200 207
Reptiles
Triassic
251
Permian
300-298
Fish
Carboniferous
354
Devonian
400
Palaeozoic Era
420
Silurian
459
Ordovician
500
Vertebrates
(backbones)
490
545
600
Invertebrates
(no backbones)
Precambrian
700
millions of years
3.5 billion years
Life first
recorded
Plants