mass extinction monday

END-PERMIAN (250 Ma) - “The Great Dying”

Severity: 1st worst

Cause: Eruption of Siberian Traps

Climate: Cold to extremely warm; ocean acidification and anoxia, ozone destruction

Aftermath: Permanent ecosystem reorganization; low O2 for >106 years

There’s good reason why the End-Permian extinction is referred to as “The Great Dying”; 95% of all marine families, 53% of all marine families, 84% of marine genera, and 70% of known land species went extinct,

The extinction likely occurred in three stages:
1. Land extinctions over ~40,000 yrs
2. Very abrupt marine extinctions
3. Second phase of land extinctions

Calcifying marine organisms such as brachiopods and bryozoa were the hardest hit, representative of ocean acidification. The last of the Cambrian fauna also died off, and this was the only known mass extinction of insects

So what exactly made the End-Permian extinction so severe? There truly was a perfect storm to make this the deadliest million years in Earth’s history.

Earth had been emerging from a moderate ice age when the largest flood basalt event in history (the Siberian Traps) occurred, which released vast amounts of CO2. The oceans then became increasingly warm, acidic, stratified, and euxinic from decaying organic matter. The atmosphere also became flooded with light (biogenically fixed) C, possibly from seafloor methane hydrates or from coal gas released as a result of heating from the Siberian Traps. Greenhouse gases soon caused global temperatures to spike, leading to massive extinction. Global euxinia in the oceans then became a severe problem, with sulfate reducing bacteria releasing large amounts of H2S, poisoning the oceans and atmosphere and thinning the ozone layer. These systems then created a cycle of positive feedbacks:
more die-offs → more euxinia → more H2S → more die-offs.

Marine ecosystems were forever changed after the extinction. Land ecosystems didn’t recover for ~5 My, and O2 levels remained low throughout much of Triassic time.

Click HERE to see all Mass Extinction Monday posts

So if you’re really wondering what my favorite part of working at The Field is, I’ve got to say it’s our 16" softball teams. 

We reenacted the Cretaceous Mass Extinction Event on Monday, a game 65 million years in the making, and history was forever altered when the Dinosaurs not only survived but beat the meteor that was meant to send them into extinction. At least we’ve got next season. 

For those of you unfamiliar, most softball games are played with a ball that is 12" in circumference - in Chicago we play with a ball that is 16", and we play mostly without gloves. It’s like hitting a melon with a bat. 

the following is taken out of our Science and Education weekly email newsletter that gets sent around to Museum staff. 


Dinosaur extinction averted!   In a stunning upset, the Field Museum Dinosaurs beat out the heavily favored Field Museum Meteors 5-1 in this season’s 16 inch softball tournament. The Dinos started strong, skunking the Meteors 5 runs in the first inning, but the gallant Meteors held fast. Aided by the courageous and sassy Karen Bean on home plate, the Meteors were able to prevent the Dinos from scoring any further runs. The best hit of the game was an RBI by the powerhouse Jennifer Edginton sending the Meteor’s Karen Bean home. These two goliaths have a long and bitter rivalry (eight weeks), but to quote FM volunteer Jan Lariviere who came to the game sporting a Meteors shirt, “I hope the better team wins.” Unfortunately this game proved that sometimes the better team does not win. Rumors recently surfaced of a rematch later this summer, so stay tuned.

Totally unbiased report submitted by James Holstein (Meteors Coach)

Standing Left to Right: Jim Holstein (S&E), Tim Bratley (IA), Megan Bradley (Education), Matthew Norwood (Guest Relations), Mireya Becker (Education), Chad Taylor (HR), Richard Lariviere (Pres), Kyla Cook (Education), Josh Engel (S&E), Eric Knowles (IT), Tom McNamara (BrainScoop), Roger Reichard (FP&O), Elena Garcia (Guest Relations) , Hector Gonzalez (Exhibits), Anne Marie Fayen (Education), Ryan Bruxvoort (Exhibits), Tom Skwerski (Exhibits), Greg Mercer (Exhibits), Cesar Rosales (FP&O)

Kneeling Left to Right: Carlin Geremias (IA), Kasey Mennie (S&E), Orion (dog), Lora Nickels (IA), Jackson (dog), Melissa Anderson (S&E), Emily Graslie (BrainScoop), Karen Bean (S&E), Beto Rosales (FP&O), Jan Lariviere (Volunteer)

S&E = Science and Education
IA = Institutional Advancement 
HR = Human Resources
IT = Information Technology 
FP&O = Facilities Planning and Operations