I saw this animation posted to Imgur by user Waffurur, showing the five biggest mass extinction events in Earth’s history (as far as we know, really):
Most people are familiar with the Cretacious-Tertiary mass extinction about 65 million years ago, which killed off the last of the dinosaurs. Well, except for birds, which are totally still dinosaurs.
Some people know about the Permian mass extinction, which left only about four percent of species alive. That’s also the one that finished off the trilobites, which is a bummer because they seem pretty cool.
!["Kainops invius lateral and ventral" by Moussa Direct Ltd. (Moussa Direct Ltd. image archive) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons](http://crypticphilosopher.com/wp-content/uploads/2016/01/688px-Kainops_invius_lateral_and_ventral.jpg "\"Kainops invius lateral and ventral\" by Moussa Direct Ltd. (Moussa Direct Ltd. image archive) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons")
On the other hand, it also brought an end to the eurypterids—a/k/a sea scorpions that reached eight feet or more in length (but were generally harmless)… Continue reading
![Horseshoe crabs mating in the Delaware Bay of Southern New Jersey, by Asturnut (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0/), GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikipedia](http://crypticphilosopher.com/wp-content/uploads/2013/07/800px-Horseshoe_crab_mating.jpg "Horseshoe crabs mating in the Delaware Bay of Southern New Jersey, by Asturnut (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0/), GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikipedia")