when was life thought to have started?

Question

like 3000b.c. also is that calender the only one that we know and use or is there astronomy dating back to the big bang or something like that. im talking evolution here folks so 2007 years ago wont be correct here. please feel free to go into any other interesting thoughts on this

Answer 1

Life is thought to have started on earth between 4 to 4.5 billion years ago. The organism was a bacteria-like cell living in an enviroment lacking oxygen gas. It might have used geothermal energy and hydrogen sulfide (H2S) to make carbohydrates from CO2 the way plants would eventually do with water (H2O) and solar energy. There is a good chance life evolved underground in hydrothermal springs. There would have an abundance of heat, water, carbon dioxide and hydrogen sulfide. More importantly, because the earth's atmosphere lacked oxygen, it also had no ozone layer. This let enromous amounts of ultraviolet radiation strike the earth's surface. Commets and meteors were also much more common, and living miles undergound would have protected early life from the harsh environmental conditions on earth's surface. The descendants of these early forms of life are known as archeobacteria. They are not closely related to any other form of life, and their biochemistry allows them to live in boiling water, and/or supersaturated brine. Life might have evolved even earlier on earth, but soon after the formation of this planet, another planet the size of Mars collided with it. This melted the earth's surface and the material thrown into orbit condenced to form the moon.

Answer 2

My, my...your question leaves out so many needed details that one is left with an empty basket to fill with words.

What do you refer to as "Life?" Is, or are Bacteria = Life?

The Earth is between 4 and 5 Billion Years Old.

Dinosaurs became extinct 65 Million Years ago. So when did they live? Maybe from the period 98 Million to 65 Million years ago.

Cambrian Age 630 to 570 Million Years ago = earliest fossil records of life on Earth. This period is represented by many small bacterium like creatures.

Refer to the book: A Guide To Rocks and Fossils, Authors: Busbey, Coenraads, Willis and Roots, Published by For City Press, 1996, Printed in Singapore.

Answer 3

Life on Earth began between 4 to 3.5 billion years ago. The Universe began with the Big Band which wasn't a bang, more like a very rapid unfolding 14 to 13.5 billion years ago. What else would you like to know. Visit my 360 page.

Answer 4

when abortionists and anti-abortionists finally agree. that's when life starts.