Credit: A zircon crystal under the microscope. Hugo Olierook/Curtin University
Life’s origins on a planet require two essential elements: dry land and water. Specifically, fresh water is crucial, as it can only exist on dry land.
Only when these two prerequisites are present can the basic components of life, such as amino acids and nucleic acids, transform into living bacteria, marking the beginning of the evolutionary process.
The earliest evidence of life on Earth, found in our fragmented rock records, dates back 3.5 billion years, with some indications suggesting it could be as old as 3.8 billion years. While scientists speculate that life may be even older, there is no concrete evidence to support this claim.
A recent study published in Nature Geoscience reveals that fresh water and dry land existed on Earth as early as 4 billion years ago. Understanding the emergence of the cradle of life—water and land—provides valuable insights into our own existence.
Imagine traveling back in time 4 billion years. As you arrive, you are surrounded by a vast ocean, tinted brown due to iron and other minerals. The sky above you appears dark orange, filled with carbon dioxide and occasional meteor flashes. It seems like an inhospitable environment for life.
This is the depiction of Earth as scientists believe it looked like 4 billion years ago. But is this truly accurate?
2024-06-08 14:00:02
Original source: phys.org
