Question

A 2024 Monash University team proposed that Earth developed rings due to this geologic period’s namesake meteor event, (10[1])which deposited a huge amount of L chondrite fragments. (10[1]-5[1])The largest known cephalopod in the fossil record, Endoceras, lived during this geologic period. Limestones from this period comprise the top of Mount Everest and contain fossils from its namesake Great Biodiversification (-5[1])Event. (10[2])The appearance of the first terrestrial plants during this period (-5[1])triggered its (-5[1])Hirnantian (-5[1])glaciation, (-5[1])ultimately resulting in a mass extinction of 85% (-5[1])of marine species. (-5[2])At the end (-5[1])of this period, a gamma ray burst (10[1])may have caused (10[1])a mass extinction, the second-largest in Earth’s history and the earliest of the “Big Five” extinctions. For 10 points, what second period of the Paleozoic (-5[1])preceded the Silurian and followed (10[1])the Cambrian? (10[2])■END■ (10[6]0[7])

ANSWER: Ordovician Period [accept Ordovician meteor event or Great Ordovician Biodiversification Event; prompt on GOBE; reject epochs “Early/Middle/Late Ordovician” or “Lower/Upper Ordovician”]
<Other Science>
= Average correct buzz position

Summary

2025 ACF Nationals04/19/2025Y2268%0%50%101.13

Buzzes

PlayerTeamOpponentBuzz PositionValue
Albert Yingzhi NyangLSEWaterloo A1710
Joseph ChambersVirginiaNYU26-5
Shardul RaoMinnesotaChicago A2610
Rasheeq AzadNorth Carolina AVanderbilt58-5
Vikshar AthreyaRutgersChicago B5910
Orion KellerVirginia TechUCF5910
Roxanne TangOhio StateStanford69-5
Justin WytmarIllinois AToronto C71-5
Yashwanth BajjiMichiganColumbia A72-5
Amogh KulkarniGeorgia StateUC Berkeley B73-5
Maude-Sophie LockmanOttawaMaryland81-5
Tiffany ZhouFloridaCornell B84-5
Gareth ThorlaksonToronto ANorth Carolina B84-5
Teigue KellyPenn StateRIT87-5
Bryan UgazArizona StateUC Berkeley A9410
June YinWUSTL BToronto B9710
Nathan SheffieldMITYale122-5
Alex AkridgeIndianaIllinois B12710
Henry BonWinona StateBritish Columbia12910
Allan LeeStanfordOhio State12910
Yared TadesseCornell BFlorida1300
Charles HangWUSTL AIowa State13010
Athena ShaddenTexasColumbia B13010
Owen MimnoNYUVirginia1300
Vinu HariharUC Berkeley BGeorgia State13010
Andy YuMarylandOttawa13010
Moses KitakuleColumbia AMichigan1300
Conor ThompsonIowa StateWUSTL A1300
Jacky XuCornell AHarvard1300
Marcus Forbes-GreenToronto CIllinois A13010
Alan XieYaleMIT13010
Nitin RaoHarvardCornell A1300
Cade ReinbergerRITPenn State1300