EVOLUTION
THE ORIGIN OF LIFE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
3.5 million years
|
|
|
5.0 million years
|
|
|
3.5 billion years
|
|
|
5.0 billion years
|
Detailed explanation-1: -Radiometric dating indicates that Earth was formed about 4.5 billion years ago. The earliest fossils resemble microorganisms such as bacteria and cyanobacteria (blue-green algae); the oldest of these fossils appear in rocks 3.5 billion years old (see Precambrian time).
Detailed explanation-2: -Specimens are usually considered to be fossils if they are over 10, 000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old.
Detailed explanation-3: -It was early in the Archean that life first appeared on Earth. Our oldest fossils date to roughly 3.5 billion years ago, and consist of bacteria microfossils. In fact, all life during the more than one billion years of the Archean was bacterial.
Detailed explanation-4: -The oldest known fossils, in fact, are cyanobacteria from Archaean rocks of western Australia, dated 3.5 billion years old.
Detailed explanation-5: -The oldest fossils on Earth show that 3.5 billion years ago there was life on our planet.