Evolution: driven by extinctions: Chixculub in the Spring (Evolution)

by David Turell , Saturday, December 11, 2021, 20:02 (866 days ago) @ David Turell

Timed by new research, still 66 mya:

https://phys.org/news/2021-12-chicxulub-asteroid-impact.html

"A groundbreaking study led by researchers at Florida Atlantic University and an international team of scientists conclusively confirms the time year of the catastrophic Chicxulub asteroid, responsible for the extinction of dinosaurs and 75 percent of life on Earth 66 million years ago. Springtime, the season of new beginnings, ended the 165-million-year reign of dinosaurs and changed the course of evolution on Earth.

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"'Time of year plays an important role in many biological functions such as reproduction, feeding strategies, host-parasite interactions, seasonal dormancy, and breeding patterns," said DePalma. "Hence, it is no surprise that the time of year for a global-scale hazard can play a big role in how harshly it impacts life. The seasonal timing of the Chicxulub impact has therefore been a critical question for the story of the end-Cretaceous extinction. Until now, the answer to that question has remained unclear."

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"The unique structure and pattern of the growth lines in fossil fish bones from the site, similar to a barcode, showed that all of the examined fish died during the spring-summer growth phase. High-tech isotopic analysis of the growth lines provided independent confirmation of this, showing a yearly oscillation that also terminated during the spring-summer growth.

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"Comparing the sizes of the youngest fish to modern growth rates enabled the team to predict how long after hatching the fish were buried. Comparing this to known modern spawning seasons enabled them to deduce what seasonal range was represented by the deposit at Tanis—spring to summer, just as indicated by the bones."

Comment: it is clear that God, if involved, picked the perfect time.