Double stranded safer from UV

I'm reading a biochemistry book and they mention that UV
absorption by single stranded DNA is about 40% higher
than by double stranded DNA at 260nm.
(Hyperchromic effect that results from the unstacking of the base pairs).

Wouldn't that suggest that double stranded RNA or
DNA would be safer from UV under the sun,
than single stranded, due to the
fact that single stranded absorbs 40% more UV?

Thus double stranded would have a chemical selection advantage
over single stranded in a high UV environment. And all this long
before any coding happened.

It also suggests something else.
IF my idea of a denaturing and annealing cycle - set up by the
sun-heat cycle is correct.
And IF this acts as a first, forced, replication process
- strands denatured then in other parts of the heat cycle annealed to
produce new hybrids of bases.
And IF we consider the UV absorption of single vs double,

THEN
It would suggest that the process of annealing and denaturing
was such that

When the UV was shining (dry heat day) the RNA was double stranded.
This would best protect it from UV.
When the UV was not shinning (wet cool night) the RNA was
single stranded. Thus it would not need UV protection in the night time.

So we have a heat cycle where when the sun comes up it is dry
and RNA or DNA is in double stranded form. Somewhere near the
end of this period (at the hottest) these doulbe stranded bases
denature, then in the night the single strands of bases anneal
in new variations - with those most W-C complementary, being
the most stable in the next day's heat.

Comment?

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Relevant Pages

  • What IF there was a heat cycle such that...
    ... strands will have G-C at both ends. ... will be protected enough not to denature while those on the ends had. ... It would set up similar coding - all based on the heat cycle and nothing more. ...
    (sci.bio.evolution)
  • Single Strand at the Start
    ... RNA is seldom found in paired strands like DNA. ... The heat cycle would produce single loose strands ... still no need for watson crick base pairing, ...
    (sci.bio.evolution)
  • Re: Double stranded safer from UV
    ... than by double stranded DNA at 260nm. ... (Hyperchromic effect that results from the unstacking of the base pairs). ... if you are looking for a chemical selection advantage to ... strands undergo hydrolysis much, much more readily than double strands. ...
    (sci.bio.evolution)