This is a great example of the shoddy, fallacious reasoning that underpins evolutionary science. This article relates how scientists have wondered why sex would first evolve when asexual cloning is a more efficient, safer, less resource intensive form of reproduction. By all accounts, asexual cloning as far as bacteria and “simple” organisms are concerned appears more adaptive than sex. Yet, sex first evolved in these simple organisms. How is this to be explained?

Consider this passage:

“Around 2 billion years ago in a world ruled by microbes, a bacterial species formed a close symbiotic partnership with another simple cell – an archaeon. The interaction was so tight that bacterial symbionts eventually colonised the insides of archaea and were gradually transformed into mitochondria – the organelles of our cells specialising in energy production. The chimeric cell grew and expanded, using the genetic material of both partners and the newly available mitochondrial energy source to forge a cell of unparalleled complexity, inventing countless eukaryotic features along the way – including sex.”

Did you catch that? This is all a story of what may have perhaps happened 2 billion years ago. There were no scientists observing any of this take place 2 billion years ago. There is no fossil record that can provide evidence that any of these molecular processes actually happened. It is all 100% speculation based on what these biologists believe to be the case about organisms today.

In logic, we call this the post hoc fallacy and post hoc analysis. We already know that many organisms today reproduce sexually. Given that fact, you can cook up any number of an infinite variety of explanations for why that is the case. You can then cull that infinite set of explanations according to your assumptions about what must be the case, e.g., certain ideas about cellular biology, genetics, and of course, Darwinian evolution. And then you pick whatever story accommodates your assumptions, but that story tells you more about your presuppositions and your understanding of the world rather than explaining the phenomenon in question or giving you new information about the world.

Post hoc explanations and “just so” stories plague all of evolutionary biology, but people think that science is still being done. They don’t realize that science is not supposed to be riddled with logical fallacies. At minimum, a scientific theory must be logically valid if it has any hope of being factually true. Amazingly, logical reasoning is not a degree requirement for science majors. At least not at Harvard or any of the American universities I know.