Mass Extinction

Ordovician

444 BCE

444 milion Years ago
86% of species lost
Grapotlite 2-3 cm length
Graptolites were sea creatures that filter feed and build colonies. Their diminishment was possibly caused by a short ice age that caused the sea levels to lower. This exposed silicate rock which sucks CO2 out of the air, chilling the planet.

Trilobites

375 BCE

375 Million years ago
Trilobites had spikey armor. They survived the first major exctinction but were mainly wiped out in the second due to land plant's roots possibly stirring up the earths nutriients up into the ocean cuasing algal blooms, which suck up oxygen out of water, causing teh trilobites to suffocate.

Permian

251 BCE

During this extinction life on earth was almost ended. The tabulate where coral that were lost during this peiriod. What happened, well the authors at cosmos magazine say "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"

Conodont

200 BCE

200 million years ago
this species was a jawless eel, that has teeth lining its mouth and throat which were the first of these structures that were built from hydroxyapatit which is a calcium rich mineral, there is no clear cause for the extinction of these creatures.

Ammonites

66 BCE

66 Million Years ago
These were killed by Volcanic activity and climate change along with the asteroid that killed the dinoursaurs. Not all were killed though and a species still is alive today.