The theory of why sex evolved is not crystal clear. Consider the article: Why Sex? Biologists Find New Explanations (complete with frantic paramecium sex movie [1]).
Let the love of wisdom come to the rescue of scientists lost in spurious biochemical effects… They are missing the very big picture, which is actually very simple. Yes, sex enables to repair seriously damaged DNA. If one strand has a gross error, coupling it with a correct strand will erase the mistake. That was obvious ever since the double helix was discovered (and one of the motivations thereof).
But there is also a more general, more philosophical point of view., which one has to take into account.
In higher animals, sex incites individuals to interact in a fundamentally non predatory way: instead of viewing the other only as a competitor, an adversary, or prey, the other can be seen as complementary, and a friend. This way, sex, acting as social attractor and social cement is immediately profitable to the sexually minded individuals. Recent, deeper studies, have revealed that even species which used to be thought as solitary, like orangutans, are not so: the much smaller females interact with males, thanks to their booming voices, at the distance of many kilometers. All together they go one way, in a coordinated fashion.
Paramecia Having Sex. Paramecia can have sex without reproduction, and reproduction, without sex.
Considered this way, sex is not just all about future generations, but also about immediate benefit to the individual. It’s about making friends. Of course it makes the individual smarter, because making friends requires mental ingenuity, thus to exert the brain muscle (so to speak).
Having friends increases one’s longevity. One can defend oneself better when more than one, or many. Being not one, but many, leads the individual to having a lower probability of being consumed. Female orangutans are informed by the males whether the forest in the (slow) direction of travel is safe, for example.
Some will object that this mechanism sure couldn’t play a role with the most primitive animals. Actually, this is not correct. The more friends, the better, even with the most primitive. For example, bacteria is much more resistant, when in films (all together now).
The argument that, the more pressed together, the better, applies also in the case of a plausible transition from prokaryotes to eukaryotes, through multicellularity (all the friends pressed together, now).
Love of the other, is also love of the self, mirrored, or not. Loving the multitude averages as the best way to love oneself.
Patrice Ayme
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P/S 1: The hypothesis above, that sex was the evolutionary created mechanism to increase sociability in species, also explains homosexuality, and makes it a mechanism facilitating survival.
I am not the first one to get the idea that sexuality, homosexual or not, helped defense. The concept, deliberately engaged, helped bring down Sparta. The Sacred Band of Thebes (Ancient Greek: Ἱερὸς Λόχος, Hieròs Lókhos) was a troop of topmost, best soldiers, consisting of 150 pairs of male lovers which formed the elite force of the Theban army in the 4th century BC. Thebes, spearheaded by the Sacred Band, ended Spartan domination. Its dominance began with its crucial role in the Battle of Leuctra in 371 BC, when the Spartan army got broken, fair and square, thanks to a number of innovations on Thebes’part.
The Middle Age European aristocracy invented something a bit similar with the Compagnon d’Armes. For example, Richard The Lionhearted’s Compagnon d’Armes was his suzerain, Philippe Auguste: they trusted each other absolutely, with their lives. When the latter had to return to France he left the former in charge of the army, to deal with Saladin.
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P/S 2: Why was such a simple, perfectly obvious idea, that sex is the essence of sociability, avoided as an explanation of the evolutionary creation of sex before? Probably because it sounds anthropomorphic: fashioning the universe in the image of humanity. However, that sometimes works; after all, humanity evolved out of the universe, and one of the fundamental driver of why the philosophical approach works is precisely that one learns a lot about the universe by looking inside.
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P/S 3: Sartre famously said: “L’Enfer, c’est les autres!“. He got it as wrong as wrong can be. L’Enfer ce n’est pas les autres, monsieur Sartre: c’est vous et les vôtres qui le somment. Hell is not others, Sartre. Only in your social, dictator loving circle. Hell is you and your Nazi loving lover. Nazism was a failure, because at the heart of the human, and even animal, enterprise is the mechanism that paradise is the multitude.
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[1]: From the article: Sex might be biology’s most difficult enigma. The downsides of relying on sex to reproduce are undeniable: It takes two individuals, each of whom gets to pass on only part of their genome. Because these individuals generally have to get fairly intimate, they make themselves vulnerable to physical harm or infections from their partner. Asexual reproduction, or self-cloning, has none of these disadvantages. Clones can be made anywhere and anytime, and they receive the full complement of an individual’s genes.
Yet despite all its benefits, asexual reproduction is the exception, not the norm, among organisms that have compartmentalized cells (eukaryotes).
Patrice Ayme's Thoughts 