THE CONVERSATION
When an asteroid struck Earth about 66 million years ago, it ended the age of dinosaurs and transformed life across the planet. The effects of that catastrophe are visible in the fossil record on land, but scientists know far less about what happened to fishes in the seas during the first

few million years after the extinction.
Like many people during the pandemic, I suddenly found myself living through long stretches of isolation and uncertainty. In 2020, while alone in my apartment in Ann Arbor, Michigan, I was finishing a study on fossil fishes from Egypt. This question of what happened to fishes immediately after the age of the dinosaurs kept troubling me.
That missing chapter represented a major gap in scientific understanding of how modern marine ecosystems emerged.
A unique opportunity
At the time, I was studying younger fossil fishes, but I kept wondering whether older rocks in Egypt might preserve clues to this critical period. During those long pandemic months, I spent countless hours reading geological reports and searching for mentions of formations with fish fossils of the right age.
Then, Hesham Sallam, my adviser, introduced me to earlier work by paleontologist and geologist Robert Speijer and colleagues who had documented rocks at Qreiya in Egypt that were deposited only about 4 million years after the asteroid impact.
That single detail changed the entirety of my Ph.D. research.