Our demand to believe in a linear and progressive evolution has always presented us with a brain that has gradually added valuable pieces and new components. But this would mean piling up patches, and it is often better – or even necessary – to go back to the foundations, if we want to innovate radically without the old shelter collapsing on top of us.
Probably to give or seek meaning to our life, we want to think that we are the result of a great process, whether divine or natural. In the case of religion, well, the principle comes by default, being part of its very structure.
However, in the case of the natural sciences, the attitude clashes a bit, because we assume that the human being is only a part of this complex story, and not its tragic end. But, over a long time, we have seen evolution as a linear, gradual and progressive process that, curiously analogous to many religious doctrines, culminates with our species.
It has not been enough for paleontologists, anthropologists, geneticists and ecologists to have explained with all sorts of details why this linear vision is highly improbable, both in its logic and in the backing of scientific evidence since the middle of the last century.
The press and the media have continued to cling to the old myth of the path of evolution, the “march of progress,” as it was baptized almost a century ago, using an iconography full of prejudices, lost links, false myths, and hopes difficult to abandon.
In spite of being a perspective scientifically discredited and totally lackluster for decades, it is still there, today, in newspapers and museums around the world, with its tired effigy of a bent monkey that little by little gains the rectitude of its back, and of its destiny.
It works well, in particular for marketing, because it sells a simple and desired version, which transforms a difficult knowledge process into an easy – and above all profitable – walk towards entertainment. It is not surprising that our most vain organ, the brain, could not escape these novelistic temptations that are embedded in the deep structure of evolutionary anthropology and its dissemination.
The most usual thing, for example, has been to take brains from independent lineages (many species of hominids have had a process of encephalization, probably for different reasons and with different mechanisms) and put them all in a single row, giving the idea of a progression. Progression that, in all probability, never existed.
The evolution of the brain, like evolution in general, follows many parallel lines, sometimes it is gradual and sometimes it is sudden (such as, for example, when it touches the genes of the regulation of development) and, above all, it does not follow a pre-established path, but rather the demands of ecology and the environment, which, in general, zigzag along millions of years without direction.