<
https://theconversation.com/giant-sea-lizards-fossils-in-morocco-reveal-the-astounding-diversity-of-marine-life-66-million-years-ago-just-before-the-asteroid-hit-210085>
"Sixty-six million years ago, the Cretaceous period ended. Dinosaurs
disappeared, along with around 90% of all species on Earth. The patterns and
causes of this extinction have been debated since palaeontology began. Was it a
slow, inevitable decline, or did the end come quickly, driven by a sudden,
unpredictable disaster?
Georges Cuvier, working in the early 19th century, was one of the first
palaeontologists. He believed that geological catastrophes, or “revolutions”,
drove waves of sudden extinction. In part, his ideas were formed by study of a
giant sea lizard, Mosasaurus, that lived and went extinct at the end of the
Cretaceous.
Charles Darwin saw the end of the Cretaceous rather differently. He thought
extinctions happened gradually, driven by everyday processes working over many
millions of years, just as sedimentation and erosion slowly reshaped the land.
The debate continued for over a century, but the idea of catastrophic
extinction gained ground as palaeontologists collected more fossil species,
timing species’ appearances and disappearances. Massive numbers of species
disappeared near the end of the Cretaceous, rapidly, around the world, both on
land and in the sea. These severe, rapid, worldwide extinctions implied a
severe, worldwide, rapid cause – a catastrophe."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics