What are the earliest known life forms found on Earth?
Q: What are the earliest known life forms found on Earth?
A: The earliest known life forms found on Earth are fossils of microorganisms in 3.46 billion year old rocks in Western Australia.
Q: When did oceans form on Earth?
A: Oceans formed on Earth 4.41 billion years ago.
Q: How long after the formation of the Earth did life forms first appear?
A: Life forms may have first appeared as early as 4.28 billion years after the formation of the Earth, which occurred 4.54 billion years ago.
Q: What is a life form?
A: A life form, or lifeform, is an organism that is living.
Q: How many species of life forms are thought to exist on Earth?
A: Estimates of the number of species of life forms on Earth range from 14 million, to as many as 1 trillion species.
Q: How many species of life forms that have ever lived on Earth are thought to be extinct?
A: More than 99% of all species of life forms that have ever lived on Earth are thought to be extinct.
Q: Where can we find evidence for existing and past-existing organisms?
A: Life forms may be found everywhere on Earth, including underground, possibly at least 12 miles deep underground; in the deepest parts of the oceans; at least 47 miles high in the atmosphere; and under test conditions it survives even in outer space vacuum conditions.
