[Ninian Dryhope]

"Uh, yes...but not all at once."

Then why do even very simple forms of life such as viruses and bacteria use the same complex code? Shouldn't there be some earlier, simpler forms of the code still extant?

[snarks_when_bored]

"Uh, yes...but not all at once."

Then why do even very simple forms of life such as viruses and bacteria use the same complex code? Shouldn't there be some earlier, simpler forms of the code still extant?

Those forms have disappeared, victims of adverse circumstances to which they could not stand up. What we see now (and in the fossil record, such as it is) are the winners (at least for a time). It seems that a certain degree of complexity in their molecular structure is required for types of organisms to persist over long periods of time.

[b_sharp]

"Then why do even very simple forms of life such as viruses and bacteria use the same complex code? Shouldn't there be some earlier, simpler forms of the code still extant?"

After 3.5 billion years? Why would they?