Which of the major mass extinction events most profoundly affected ammonites?

Question

BlackTom AI · Accepted Answer

To approach this question, let's review how ammonites fared across major extinction events and which event left the strongest imprint on their lineage.
Option a: End Permian. This was the most severe global extinction in Earth's history, wiping out a huge fraction of species across many groups. However, ammonoids did not disappear entirely at this boundary; they endured into the Early Triassic, albeit with evidence of significant turnover and reduced diversity. Thus, while impactful, the End Permian event did not eradicate ammonites nor leave as profound a selective stamp on them as the later event.
Option b: End Cretaceous. The End Cretaceous (K-Pg) boundary marks the mass extinction associated with the asteroid impact that killed the non-avian dinosaurs. Ammonites were driven to global extinction at this boundary, vanishing from the fossil record at the K-Pg event. This represents a major, decisive wipeout of their lineage, more so than in other mass extinctions, making it the event that most profoundly affected ammonites.
Option c: End Triassic. The End Triassic extinction opened ecological space and caused faunal turnover across many groups, but ammonoids persisted into the Early Jurassic and show a pattern of diversification after this boundary. Therefore, while it caused changes, it did not have the deepest and most lasting impact on ammonites overall.
Option d: End Ordovician. The End Ordovician extinction primarily affected marine invertebrates like graptolites and many shelled organisms in Ordovician seas. Ammonoids were not a dominant or defining group at this time (they are more characteristic of the Mesozoic), so this event is not the primary driver of ammonite history and would not be described as the most profound impact on them.
In summary, while multiple mass extinctions reshaped marine life, ammonites experienced a catastrophic, near-total extinction at the End Cretaceous boundary, whereas they persisted through or recovered from the others to varying degrees. This makes the End Cretaceous the event that most profoundly affected ammonites.

Which of the major mass extinction events most profoundly affected ammonites?单项选择题

类似问题

Which of the following statements concerning past or present mass extinctions is TRUE?

Extinctions have occurred throughout Earth’s history. What is accurate about the history of extinctions?

Which of the major mass extinction events most profoundly affected ammonites?

Which of the major mass extinction events most profoundly affected ammonites?

Which factors contributed to the great extinctions at the end of the Permian, Triassic, and Cretaceous era? Select 3 correct answers.

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单