Did Life on Earth Start 3.7 BYA?

In summary, some researchers have found rocks in Greenland dating back 3.7 billion years ago that contain hematite tubes, which they believe may be evidence of early life forms. However, the idea is still debated as some believe the structures may have formed through a natural process rather than being created by living organisms. The presence of oxygen in the atmosphere during that time is also a point of contention.
  • #1
BillTre
Science Advisor
Gold Member
2,486
9,720
Since the planet is only 4.55 BY old, that might be considered a fast start.

Some people have found some rocks (3.7 BYA) in Greenland with what they think are indications of life (short article, a bit longer article). The indicators are primarily microscopic hematite tubes (some say, similar to tubes of biological origin found in more modern vents).

This is of course controversial.

Hematite is an oxidized form of iron (Fe2O3). The atmosphere at that time had little or no oxygen. They hypothesize that there were microbes living at the equivalent of mid-ocean vents, where hot water extracts minerals from the rocks that could provide an initial energy source for the first life forms (generally a popular explanation now for the first life forms).

I'm not clear on how the hematite becomes oxidized in these conditions.
Due to actions of the living bacteria (or whatever), or from a fossilization process after they die?
Is the oxygen coming from the dissolved minerals from the vents?
 
  • Like
Likes Buzz Bloom
Biology news on Phys.org
  • #2
BillTre said:
This is of course controversial.
Hematite is an oxidized form of iron (Fe2O3). The atmosphere at that time had little or no oxygen.
"Controversial?"
 
  • #3
Bystander said:
"Controversial?"
Not everyone believes the rock structures are the result of living things.
 

1. When did life on Earth begin?

Life on Earth is estimated to have begun around 3.7 billion years ago (BYA).

2. How do scientists know that life started 3.7 BYA?

Scientists have used various methods to determine the age of the oldest known fossils, as well as the age of the Earth itself. These methods include radiometric dating, which measures the decay of radioactive elements, and examining the geological record for evidence of ancient life forms.

3. What was the first form of life on Earth?

The exact first form of life on Earth is still a topic of debate among scientists. However, the oldest known fossils are of single-celled organisms called stromatolites, which lived around 3.7 BYA.

4. How did life start on Earth?

The exact process by which life began on Earth is still unknown. However, scientists have proposed various theories, such as the primordial soup theory, which suggests that the early Earth's atmosphere and conditions were conducive to the formation of organic molecules that eventually led to the formation of simple life forms.

5. Has life always existed on Earth?

It is currently believed that life on Earth began around 3.7 BYA. However, some scientists theorize that life may have existed on Earth even earlier, but it has not been discovered yet due to the lack of evidence. Additionally, some scientists believe that life may have originated elsewhere in the universe and was brought to Earth through meteorites or other means.

Similar threads

Replies
3
Views
3K
  • Biology and Medical
Replies
4
Views
2K
  • Biology and Medical
Replies
1
Views
818
  • Biology and Medical
Replies
1
Views
857
Replies
6
Views
3K
Replies
6
Views
2K
  • Biology and Medical
Replies
5
Views
3K
  • Biology and Medical
Replies
1
Views
875
Replies
6
Views
5K
Replies
2
Views
1K
Back
Top