One-hundred million years ago the earth was very different. The landmasses were in very different places. Largely covered by dense sweaty rain forests and vast deserts.
A map would have looked different as well. The majority of land masses were gathered around the equator. South America and Africa was still linked as one land mass, and because of the hotter planet, large parts of Europe and North America were submerged.
This led to substantial differences, for instance Greenland which is now in cased in a mile thick layer of ice would have had a climate more like Florida and happily supported animals such as alligators. Ocean to a thought to be about 20 degrees warmer, and there is no evidence there was any Ice caps.
Also with many of the mountain range that is not yet formed the average world temperature was around 2 degrees warmer merely because of this, and in total the average surface temperature is thought to have been around 7 degrees warmer.
The carbon dioxide levels in the atmosphere was thought to be anything from 2 to 15 times higher than they are today.
The idea that microbes can survive 100 million years at the bottom of the ocean with barely any oxygen and incredible pressure is astounding, but it says he gives more credence to the idea that microbial life could have once arrived on earth via meteors (while not the subject of this article it should be noticed that this does not remove the need to understand how life initially formed it nearly moves it elsewhere-nor does it go into what caused life to form) as if it can can survive largely without oxygen under incredible pressure with very little light for millions of years it should likely also be able to to stay alive through millions of years on a meteor flying through space.
Interestingly it is thought these seabed microbes can survive on millions of times less oxygen than similar microbes on the surface require.
This new discovery demonstrates the incredible power of Life to hold on it will be interesting to see what these discoveries lead to.