Extinction

Earth Began

1 CE

4.5 Billion Years Ago

Ordovician

2

444 million years ago
The graptolite extinction. These sea creatures extinction was over about a million years was probably caused by a short, severe ice age that lowered sea levels, possibly triggered by the uplift of the Appalachians. 86% of species lost. 2-3 cm in length. The environment was ice, snow, and many other elements with an ice age.

Devonian

3

375 million years ago
The trilobite extinction. New plants were rising up and the roots likely sucked the oxygen out of the water which in turn killed the bottom dwellers like the Trilobite. 75% species loss. Mostly bottom dwellers died off. It was dark at the bottom of the ocean.

Permian

4

251 Million Years Ago
The tabulate coral extinction. A cataclysmic eruption near Siberia blasted CO2 into the atmosphere. Methanogenic bacteria responded by belching out methane, a potent greenhouse gas. Global temperatures surged while oceans acidified and stagnated, belching poisonous hydrogen sulfide. 96% species lost. Almost ended all life as a whole. Gases were floating around and temperatures rose in the atmosphere.

Triassic

5

200 Million Years Ago
The conodont teeth. No clear cause has been found. 80% species loss. Not sure what the environment was like since there is no cause.

Cretaceous

6

66 Million Years Ago
The ammonite extinction. volcanic activity and climate change already placed the ammonites under stress. The asteroid impact that ended the dinosaurs’ reign provided the final blow. Only a few dwindling species of ammonites survived. 76% species loss.