Sexual Reproduction

[ck1]

What are the earliest organisms known to exhibit this and why was it so successful? There must have been a transitional period where single-sex organisms had no idea what to do with themselves and were losing out to their asexual counterparts, making the advantage of variation meaningless in comparison?

[Mamyalynne]

There may be info here or in the referenced links within.

https://en.wikipedia.org/wiki/Evolution_of_sexual_reproduction

[fiction-factory]

It just comes naturally. Animals manage it despite never reading a book or being taught

[webbo3]

diatoms i think

[Old_Geezer]

I believe that bacteria exchange genes all the time. Must just have formalised the process as evolution produced more complex 'higher level' creatures. So back in prehistory anyways.

[beso]

Although bacteria exchange genes it is not a form of sexual reproduction. Sexual reproduction involves meiosis in which the cell undergoes a haploid phase where it has only a single copy of each chromosome then combines with another to return to being diploid.

Sexual reproduction far predates the emergence of multi-cellular organisms.

The genes for the core processes of sexual reproduction are widespread among Eucaryotes (organisms with a well defined cellular nucleus), even those that reproduce asexually, indicating that it was likely present in the earliest of them, going back at least 1.5 billion years.

[Canary42]

Sexual intercourse began
In nineteen sixty-three
(which was rather late for me) -
Between the end of the "Chatterley" ban
And the Beatles' first LP.

Up to then there'd only been
A sort of bargaining,
A wrangle for the ring,
A shame that started at sixteen
And spread to everything.

Then all at once the quarrel sank:
Everyone felt the same,
And every life became
A brilliant breaking of the bank,
A quite unlosable game.

So life was never better than
In nineteen sixty-three
(Though just too late for me) -
Between the end of the "Chatterley" ban
And the Beatles' first LP.

Annus Mirabilis Philip Larkin (1922-1985)

[Mozz71]

Larkin really was a late starter.

[AZardoz]

That Canary sure can sing !

[ck1]

So it was 1963 then, must have coincided with the reduction in global stork numbers!

[Old_Geezer]

http://www.smbc-comics.com/comic/ew-2