What modern organisms are thought to be most like the first life-forms on Earth?

Answer 1

Probably either cyanobacteria or archaea, both of which flourish today in all kinds of wet environments.

The question makes the assumption that the first life forms on Earth were what we would now refer to as organisms. Various authorities define "life-form" differently; pre-cellular arrangements of molecules may or may not be considered life.

Cyanobacteria and Archaea are the oldest known unicellular organisms still in existence. There is some debate regarding the proper taxonomy of archaea, at least when it comes to its grouping into phyla.

It is difficult to distinguish whether the earliest evidence of life is from cyanobacteria or from archaea, but evidence has been found dating from between #3.48# and #4.1# billion years old.

The "RNA world" hypothesis suggests that, before cellular life-forms, there might have been even more primitive self-replicating molecules. This is similar to the idea that life evolved from a primitive form based on self-replicating RNA strands.

Sign up to view the whole answer

By signing up, you agree to our Terms of Service and Privacy Policy

Sign up with email
Answer 2

Simple prokaryotic organisms, like some bacteria and archaea, are thought to be the closest modern organisms to the first life forms on Earth.

Sign up to view the whole answer

By signing up, you agree to our Terms of Service and Privacy Policy

Sign up with email
Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

Not the question you need?

Drag image here or click to upload

Or press Ctrl + V to paste
Answer Background
HIX Tutor
Solve ANY homework problem with a smart AI
  • 98% accuracy study help
  • Covers math, physics, chemistry, biology, and more
  • Step-by-step, in-depth guides
  • Readily available 24/7