Gary sent in this link – www.dailymail.co.uk/sciencetech/article-10070379/ … a mass extinction in Africa and Arabia – 30 million years ago. According to the Daily Mail, it was due to climate change. Swampy conditions became icy. Yes, as in ice. A bit of journalistic imagination here it would seem as the earth became cooler, we are told, ice sheets expanded and sea levels dropped, etc. Seems like something big happened and affected the climate – shutting out the lovely sunshine and causing the globe to cool. How that made Africa and Arabia icy is the mystery – unless they are talking about the bottom of Africa only.
In addition, forests disappeared, and the environment switched to savannah grassland. Where have we heard this before? Could it have something to do with a movement at the axis of rotation as new cooler weather animals replaced the swamp dwelling varieties? There is plenty of evidence from Kenya that climate switched repeatedly from a watery one to a dry one – and not just at 30 million years ago. That is probably related to shfts in the monsoon track, but a sweeping change like a swamp to cool conditions is a good deal more drastic. Actually, this appears to represent further evidence that catastrophic events mark geological boundaries as it occurs at the Eocene-Oligocene transition. For the full article go to https://www.nature.com/articles/s42003-021-02707-9