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| Geologic Periods |
 Title text: Geologists claim it's because the earlier Cenozoic used to be called the Tertiary, but that's just a ruse to hide the secret third geologic period, between the Neogene and the Quaternary, that they won't tell us about. |
Explanation
| Period | Dates (millions of years ago) | My Favorite Part | My Biggest Complaint | Explanation |
|---|---|---|---|---|
| Precambrian | 4500-539 | Life develops | Snowball Earth episodes | The Precambrian (italicized in the comic since it's not a geologic period) is the first 88% of Earth's history, including the time 4.1 to 3.4 billion years ago when life on Earth began. The Snowball Earth hypothesis says that during some time spans in the past, Earth became nearly or entirely frozen, with no liquid water on the surface. It's related to the idea of the icehouse Earth, times when the planet fluctuates between glacial and interglacial periods (such as now). |
| Cambrian | 539-487 | Trilobites! | Evolution could stand to calm down a little | The Cambrian explosion was a sudden radiation of complex life forms when nearly all important animal phyla, or precursors to them, appeared. |
| Ordovician | 487-443 | Earth might have had rings | Scary volcanic eruption in North America | |
| Silurian | 443-420 | First land animals | Earth's newfound mold problem | |
| Devonian | 420-359 | Big mountains in Boston | Yeah, sure, what those giant killer fish needed was armor | |
| Carboniferous | 359-299 | Cool forests | Bugs too big | The 'bugs' in this period included the largest-ever known land invertebrate, a 2.6-m (8.5-ft) millipede-like animal; the largest-ever known flying insect, resembling a dragonfly with a wingspan of ~75 cm (30 in); and a 70 cm (2 ft 4 in) scorpion. |
| Permian | 299-252 | Pangea | Google "The Great Dying" | Pangaea was the most recent supercontinent containing nearly all of Earth's landmass. The Great Dying, more formally known as the Permian-Triassic extinction event, occurred at the end of the Permian and is the most severe of Earth's 'Big Five' mass extinction events. In it, 81% of marine species and 70% of terrestrial vertebrate species were wiped out. |
| Triassic | 252-201 | Tanystropheus | Damage to Canada still visible from space at Manicouagan | Tanystropheus was a verrrry long-necked dinosaur. Manicouagan Reservoir is a ring-shaped lake, the remains of the crater caused by a 5-km (3-mi) asteroid hitting Quebec. |
| Jurassic | 201-143 | Birds | Parasitoid wasps | |
| Cretaceous | 143-66 | Raptors | Raptors | Raptors |
| Paleogene | 66-23 | Pretty horseys!!! | Paleocene-eocene thermal maximum | The Paleocene–Eocene Thermal Maximum was a time where the global average temperature rose by around 5-8 °C is a relatively short period of time. |
| Neogene | 23-2.6 | Forests of Dracaena dragonblood trees | Zanclean flood | The Zanclean flood is theorized to be the flood that refilled the Mediterranean Sea. |
| Quaternary | 2.6-present | Burrito invented | Whoever picked the name for the third period of the Cenozoic |
Transcript
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