The Unseen Driver: Exploring the secrets of evolution

“All changed, changed utterly.

A terrible beauty is born”

-William Butler Yeats

Telling a good story is far from an easy task. We need authors, characters, a dazzling plot, and a considerable number of external factors. But above all, we need all these elements to interact with each other and modify their environment as they do. So, what happens when we want to tell the story of all the organisms that live or have lived in our world? Obviously, the complexity multiplies, but luckily, the beauty of the plot does too.

Today, we are going to tell the story of evolution, although in reality, its story tells itself, and we are indeed witnesses/parts of evolution. Humans, monkeys, ferns, bacteria, insects, and all living organisms present today are the literal manifestation of evolution.

But then, what does this theory of biological evolution consist of? This word is undoubtedly tied to a person, Charles Darwin. And although the idea of evolution as an intrinsic driver of events in the natural order of things has existed since ancient times, no idea has been able to revolutionize human thinking like the evolutionary theory through natural selection proposed by the wonderful Carlitos.

If we have to make it short:

Evolution= changes in organisms over time.

Natural selection= was the means Darwin used to explain how biological evolution occurs, a phenomenon that involves a differential reproduction of genotypes (genetic information of a particular organism) of a population (a group of individuals of the same species). It is worth clarifying that organisms do not evolve, as their lifespan is too short to witness it; only populations evolve.

We evolve because we change, and if these changes provide some kind of benefit or adapt better (generate differences in the survival of individuals who carry them), they will prevail and generate greater reproductive success, i.e., they will be inherited.

And here, it is imperative to talk about how these changes are inherited and talk about DNA, the most amazing molecule in the world. In nature, these changes, which we tire of discussing, generally manifest through mutations. The information contained in DNA is transmitted, from generation to generation, from parents to offspring. We can even think that all the DNA that exists in the world, somehow, comes from an incessant line of successful ancestors.

At this point, we have identified the two fundamental pillars for evolution to exist: natural selection and mutations. And its vehicle, heritage.

Richard Dawkins, in his work “Climbing Mount Improbable,” makes us dizzy and lifts us up again around the “how” of this evolution over the years, centuries, and complications that come with surviving, but surviving with fertile and competent offspring:

“The Darwinian explanation of why living things do so well at what they do is straightforward. Their fitness is the product of the accumulated wisdom of their ancestors. But it is not wisdom you have learned or acquired. It is a wisdom that was given to them through successful random mutations, wisdom that was then selectively, not randomly, recorded in the genetic database of the species.”

And how wise was little Richard, who helped us climb a somewhat complicated mountain with a bunch of converging examples and stories. While we would like these examples to be represented before our eyes, unfortunately, the fossil record tends not to be very gracious (a detail discussed by another genius like Gould), and that is when speculation about intermediate stages becomes a fundamental pillar in the search for the evolutionary history of a species or group of them.

The elephant’s trunk is a case that fits the problem of not having all the pieces for the evolution puzzle. This trunk doesn’t contain bones and therefore doesn’t fossilize, but we don’t need to be experts to be convinced that this trunk was a simple nose at some point (long ago). A simple nose that is now equipped with over fifty thousand muscles, controlled by an equally complex brain, and capable of being used with immeasurable force. The trunk also carries out the most delicate operations, such as plucking seed pods, acting as a siphon, acting as a finger, as a trumpet, or even as a loudspeaker. From here, it has social functions attributed to it, from caresses and sexual innuendos to fights when the male seeks to dominate.

But, again, evolution has no fate or purpose. A simple nose did not set out to become a multi-tasking trunk, let alone anything else. Probably, the ancestors of elephants went through a continuous series of intermediate forms between a less elongated nose towards a more elongated one, which involved a smooth and gradual succession towards thicker muscles and more intricate nerves to perform its job better.

This transition also occurred in the ancestors of tapirs, sea elephants, and trunked rats. Are these animals closely related to elephants? No. And to each other? Neither. But they all converge on the presence of a long nose, which they developed independently and for different reasons.

The story of the elephant’s trunk doesn’t end here because its evolution will never end, and if we are rigorous and astute enough to understand that we not only form part of but modify thousands of evolutionary stories every day, perhaps we can understand the miracle of change and, why not, understand a little more about the world around us.

References:

• Dawkins, R. (1996). Climbing Mount Improbable. Viking, Londres. W. W. Norton & Company