Sex …

“The question of how sexual reproduction, and specifically the two distinct sexes (anisogamy—small motile sperm and large sessile eggs), evolved from asexual ancestors is considered a major topic of research in evolutionary biology, sometimes referred to as the “queen of problems”. While Charles Darwin himself acknowledged he did not know the final cause of sexuality, modern evolutionary biology has developed several, though not definitively proven, hypotheses to explain it. “

As we can see, as usual, the Darwinians are clueless.
However the Vedas explains fully the origins of sex attraction and how the original sex attraction has been interlinked within the external energies of Divinity for specific purposes and not just sex pleasure,  which is something else the Darwinian can’t explain , the orgasm , and its not only restricted to humans .  The Vedas explains in detail how living beings who feel no immediate attraction for the Supreme Personality of Godhead and His families and activities are injected into the material energies , from the Brahman regions or the Tatastha regions where living beings are expanded from the first expansion of Krishna,  Balarama. So , via a transformation of the Supreme Lord and the Supreme Goddess of fortune , who are addressed as Sambhu or Sadasiva and Ramadevi or Durga Devi .
These transformations or expansions of Radha Krishna who appear curiously in touch with the material energies, but very much like yoghurt and milk  that are one but different .These expansions  provide the material bodies for the beings to be injected into matter . They are generated with male and female sexual organs . The whole idea is that in order to receive a machine made of the material energy that the soul to temporarily inhabit , one requires a consistent and constant supply of machine like bodies because the time factor is added to matter , due to harmful karma , which means death and rebirth and a reevaluation which is healthy . This is so because the living beings need to  continually experience and learn and live out their Karmic synchronicities of their independent meanderings within the universe.
Thus, the perfect arrangement of an entangled and responsive universe has arisen to facilitate free will and determinism with the machines of the bodies producing many more machines ad infinitum by sex desire , thus the whole material world is working under sex desire in every species of life

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