Does the human species continue to evolve ?

© Image generated by DALL-E AI for Presse-Citron

The assertion of some eminent figures, such as David Attenborough (British writer and naturalist), that human evolution has reached its end, encounters marked skepticism within the specialized scientific community. Despite the colossal transformations that man has imposed on his habitat, the subtle mechanisms of evolution and natural selection continue to exert their influence on our species. Nevertheless, the question remains: in what proportions and in what forms do these processes manifest themselves??

The hypothesis of an evolutionary stagnation of humanity is strongly refuted by experts in the field. Jason Hodgson, an anthropologist and evolutionary geneticist at Anglia Ruskin University, argues convincingly that “all living organisms that are part of a population are constantly evolving.” 60~/em>”. This perspective is supported by John Hawks, a paleoanthropologist at the University of Wisconsin-Madison, as well as Stephen Stearns, professor emeritus of ecology and evolutionary biology at Yale. These eminent researchers agree that human evolution continues inexorably on its course, although its manifestations may sometimes escape our immediate perception.

The mechanisms of human evolution

To understand the sustainability of human evolution, it is fundamental to grasp the subtleties of the mechanisms behind ;#8217;work behind this one. Each newborn baby carries within him an average of 70 new genetic mutations, spontaneous variations which do not come from his parents. These alterations can be transmitted to subsequent generations, thus gradually modifying the genetic landscape of our species.

In addition to these mutations, other processes shape our evolution. Genetic drift, a random phenomenon that is particularly significant in small populations, alters the frequency of alleles. Gene flow, for its part, results from migratory movements, instilling new genetic diversity within existing populations.

Sexual selection also plays a major role, preferences in terms of partners influencing the transmission of certain traits. At the same time, natural selection, often confused with evolution itself, modulates the survival and reproduction of individuals according to environmental constraints. Hodgson emphasizes that this mechanism is particularly effective in large populations, thus providing a breeding ground for the emergence and diffusion of advantageous alleles.

These complex processes have shaped our lineage dating back to our common ancestor with chimpanzees and bonobos, our closest living relatives. It is important to note that we did not evolve from these current great apes, but from a now extinct lineage of primates< /strong>, which distinguished itself from the common precursor of chimpanzees and bonobos at some point in our evolutionary history.

Concrete evidence of recent evolution

Recent studies offer tangible illustrations of human evolution in progress. In 2014, the work of Jason Hodgson highlighted a rapid adaptation of local populations to malaria in Madagascar, revealing the rapid spread of a protective genetic variant over the last two millennia. This discovery demonstrates the considerable influence that selective pressure, such as an endemic disease, can exert on the genetic heritage of a population.

Another edifying example of our recent evolution is the appearance of the lactase allele, allowing the digestion of lactose in adulthood. This trait has spread to some populations in the Middle East, Europe, and Africa in response to animal domestication and milk consumption. Hawks also points out that the frequency of this allele continues to increase.

These compelling examples demonstrate that human evolution is an ongoing process, shaped by myriad environmental, cultural, and biological factors. The latter also emphasize that evolutionary mutations can occur over relatively short time scales, sometimes within a few centuries or millennia, a pace considered rapid in the context of evolution.< /p>

Evolutionary mechanisms therefore continue to shape our species. Undoubtedly, environmental changes and advances in modern medicine influence these processes, but we, Homos sapiens, are always evolving. Even if these modifications are not easily perceptible to the naked eye.

• Human evolution, despite the transformations in our environment, is following its course.
• Genetic mutations and certain processes such as natural selection still impact our species and continue to modify it.
• Recent examples, such as resistance to malaria in Madagascar and the digestion of lactose, clearly prove the veracity of this theory.

📍 So you don't miss any news from Presse-citron, follow us on Google News and WhatsApp.

[ ]