What is the missing link, and why is it a myth?

When will the missing link be found? What if they have already found it? How many could there be?

The idea, or rather, the myth of the missing link has had a great impact both in the scientific community and in popular culture., although in itself it is an idea that arises from a somewhat simplistic interpretation of what evolution is as a process.

There are many who have gone in search of it, but each time they have "found" it, they have ended up discovering that there were more. Next we will take a closer look at the missing link controversy, its origins and its repercussions at the popular level.

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The missing link: what exactly is it?

Colloquially, the expression "missing link" refers to fossils of intermediate forms between two species of which there are remains and that it is known that one could descend from the other. In other words, a missing link, understood in popular culture, the media and sectors with a knowledge non-expert on evolutionary theses, is that intermediate stage in the fossil record that is still to come. be discovered.

This expression is highly controversial in the scientific field because it is not appropriate at all based on what is known today about evolution. The idea of ​​the missing link implies thinking that species develop in a linear fashion, and that they going from stage to stage, all of them more or less defined, abruptly and clearly bounded. That is to say, implies thinking that one species evolves to another and then to another but suddenly, being able to establish a very clearly visible before and after.

Although it is clear that within an evolutionary lineage there will be organisms very different from the previous ones, it should not be understood that evolution has occurred suddenly. Evolution is a gradual process which takes place over thousands of years in which subtle modifications are introduced into a set of individuals, which will pass on to the following generations depending on how adaptive they are with respect to the demands of the environment in which they live that species.

Taking this into account, if the fossil remains of two individuals are taken that are believed to have a direct evolutionary relationship, suspecting that one descends from the other, among them there will not be one or two "missing links", but as many as generations have passed since one lived until the other lived. The descendants of one and the ancestors of the other would all be "missing links", individuals who staged the evolutionary process that gave rise to the most modern individual.

It is for this reason that, from a scientific point of view, it makes no sense to talk about missing links, since there would be a practically endless number of them. Own Charles Darwin He already spoke that between two forms there could be an endless number of intermediate forms, of which many of them will never find their fossil since of all the forms of life that have ever inhabited the planet, very few are "lucky" to leave remains.

Despite this scientific fact, there are not a few media outlets that tend to call any fossil recently found as the "missing link", especially if it has to do with the evolutionary history of beings humans. As soon as a form is found between one hominid and another, the newscasts, newspapers and others have no qualms about using the "missing link" crutch to sell headlines. It is, without a doubt, a concept that had its origins in science and that has transcended popular culture.

Origins of the idea

Although Charles Darwin sensed that, once his work was popularized, many would be desperately searching for the link that connected primates with humans, We owe the idea of ​​the missing link to the German naturalist Ernst Haeckel. Without wanting to or drinking it, this scientist gave the world a concept that would become a widespread myth both in the scientific community of the 19th century and in popular culture and the media.

Haeckel was highly influenced by evolutionary theses and considered that evolution was a process of progress, in which all the forms range from simpler to more complex structures and functions, with the human species being at the top of the evolutionary line. Based on these ideas, Haeckel dared to make a diagram in which he described an evolutionary sequence for the human being.. In it he drew 24 figures ranging from the simplest of microorganisms to the human species.

Number 23 called attention, since it was an ape-like being, drawn from behind and that was between number 22, the primates, and number 24, the humans themselves. This figure 23 was his interpretation of the intermediate stage between monkeys and men, the “missing link” that supposedly connected the world of human beings with that of animals. He even gave it a name: it is the Pithecanthropus alalus or speechless ape-man.

For Haeckel, the human trait that most differentiated us from animals was language., an idea that today is still quite valid both in scientific and not so academic circles. He speculated that bipedalism and the humanoid form came first and, later, mental abilities developed which gave rise to spoken communication. Thus, the missing link of him was a being similar to humans but did not have the ability to speak.

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From the scientific circle to the world

The idea of ​​the missing link and, also, the ideas of evolution themselves aroused conflicting opinions within the scientific community. Due to different social and cultural factors, even among the most meticulous and rigorous scientists there were some who did not quite believe that species were evolving over time. passage of time and, much less, did they want to accept that human beings descended from monkeys, although it is true that we do not descend from them directly, but we are related.

The less evolutionary scientists insisted that if Darwinian ideas were true, then What were the defenders waiting for to show the world that ape-man that Haeckel had commented on? And as a consequence of this, many evolutionists embarked on a true paleontological fever in search of the missing link, the connection between primates and humans.

The list of people who embarked on the hunt for the missing link is very long, and many of them found remains of both possible hominids and other mammals, but The case of a Dutch doctor named Eugène Dubois is especially striking.. This researcher moved to Java in 1890 to carry out some excavations in the place and had a lot of Good luck because he found the remains of a hominid, a fossil that we know today corresponds to the of a erectus.

This finding did not go unnoticed and, in fact, the media at the time gave it media coverage, naming it Java Man. They had no qualms about calling it the missing link and Haeckel himself even went so far as to say that these were the remains of the Pithecanthropus alalus that he had predicted would one day be found. Apparently, what confirmed the theses of Darwin and other evolutionists had been found.

However, this was not convincing enough proof for many critics of evolution. In fact, that these remains had been found did not quite demonstrate the relationship between primates and humans. Yes, he was apparently an intermediate form but he could also be some kind of ape that had nothing to do with humans. If related to our species, there should be other intermediate forms that look a little more like humans.

This, which apparently could be a criticism of the creationists, became the best argument for the evolutionists. The search for new links went further and, in fact, It is thanks to this obsession with finding intermediate forms between what had already been found that has contributed to the anthropology of the 20th century.. However, he has also contributed to very misconceptions about the notion of evolution and has given strength to the myth that it occurs in a linear rather than a tree-like fashion with different lineages.

Repercussion in popular culture

At the beginning of the 20th century, there were very racist and supremacist ideas about “savages”. Even within the scientific community it was thought that the tribes of Africa, Asia and the Amazon were a clear example of what the ancestors of modern human beings were like. The white man was seen as the most evolved example within the human species., while the rest were intermediate or little evolved forms.

But within popular culture things went even further. Many circus companies wanted to take advantage of the "boom" of the idea of ​​the missing link to do business, and one of them succeeded in spades. Antonio the Great Farini, aka William Leonard Hunt, struck gold by introducing the world to what was called a living missing link: Krao. It was about a Laotian girl with hypertrichosis, that is, more hair on the body than normal. The Great Farini introduced her as the member of a simian tribe, all of them hairy and tree-dwelling, taking advantage of a girl's sad medical condition.

Today the missing link continues to have a great impact in our popular culture. It doesn't take a very deep investigation to see that, as soon as a hominid bone is discovered, the media can't resist making headlines like “Is this the missing link?” since the idea of ​​where we come from and from whom we could descend calls much the attention. In fact, if we put “missing link” in our search engine and specify that we want to search for news, we will get some 43,000 entries that show how alive this myth is still.

Bibliographic references:

• Gregory, T.R. (2009) Understanding Natural Selection: essential concepts and common misconceptions. Evolution: Education and Outreach 2:156–175
• Kjærgaard, P. c. (2010) The Darwin Enterprise: From Scientific Icon to Global Product. History of Science 48:105–22
• Kjærgaard, P. c. (2011) Ida and Ardi: the fossil cover girls of 2009. The Evolutionary Review 2:1–9
• Kjærgaard, P. c. (2011) Hurrah for the Missing Link!': A History of Apes, Ancestors and a Crucial Piece of Evidence. Notes and Records of the Royal Society 65: 83–98
• Kjærgaard, P. c. (2018) The missing link and human origins: understanding an evolutionary icon. In Perspectives on Science and Culture. ISBN: 978-1-61249-521-7
• Richter-Boix, A (2018). The missing link: the construction of a myth. EvOikos. Taken from https://andaresdelaciencia.com/2018/06/17/el-eslabon-perdido-la-construccion-de-un-mito/