Homo neanderthalensis is currently the best-known ancient human. Since the discovery of a skull in 1829 in Engis (Belgium), the collection of fossil remains has grown to include over 500 specimens, with around 30 complete individuals.
This higher frequency of remains has allowed for numerous studies that have gradually debunked the false idea of Neanderthal man as a wild and brutal being who could not be related to our species, Homo sapiens.
However, many questions remain open today among those studying this topic. Among them, we highlight the central axis of this work: the extinction of Homo neanderthalensis, which occurred approximately 40,000 years ago (Mellars and French, 2011, p. 623). Therefore, in this study, we will take a brief look at and analyze the main theories that researchers handle.
Homo neanderthalensis
Homo neanderthalensis is situated throughout the Middle Paleolithic period, from approximately 300,000 years ago until around 28,000 years ago. We can find it in this period across a very broad geographical area that spans from the Near East and western Siberia to Western Europe. According to Rosas (2010), we can differentiate two different climates within this space: one in the north, heavily influenced by glacial-interglacial cycles; and another in the south, where the climate would be less extreme. All of this proves the great "biological and cultural versatility" that these hominins had.
Their social life is also characterized by elements known as typical of a "modern" behavior. Among them, stands out the awareness of death, since Neanderthals are the first documented humans to bury their dead intentionally. On the other hand, the complex organization of space and systematic hunting of large herbivores demonstrate important long-term coordination and foresight capabilities (Rosas, 2010, p. 85).
How did they disappear?
The disappearance of the Neandertal begins around 45,000 years ago, with the last evidence of their presence – 28,000 years ago – located in southern Iberian Peninsula (Rosas, 2010, p. 107). But what led to such a disappearance? To this day there is no clear answer, so in this section we will take a look at the main theories, which we have classified into three groups:
1) Relation with Homo sapiens
One of the most highlighted and supported hypotheses is that once both species started to share the same environment and interact, a process of hybridization would have occurred, through which Homo neanderthalensis would have gradually lost its genetic identity in favor of anatomically modern humans (Burton et al., 2011).
On the other hand, some authors like Houldcroft and Underdown (2016) defend the idea that a decisive factor in extinction would be the transmission by Homo sapiens of certain diseases for which the body of the opposing species was not prepared. Thus, they take as reference the case of the diseases brought to America during the conquest.
In contrast, other hypotheses are based on competitive exclusion. Evidence of violence in the archaeological record is scarce, but this does not imply that it can be ruled out that conflicts between sapiens and Neandertals took place (Rosas, 2010, p. 114). Another more supported theory is by Paul Mellars and Jennifer French (2011), who develop the idea that it was the dominance of better resource acquisition techniques and food processing methods that gave Homo sapiens an advantage. This superiority could also be linked to the domestication of the wolf-dog, which would have been used for hunting, providing additional food; and even as pack animals in some cases. Additionally, dogs could serve as protection and warning against dangers (Shipman, 2015). All this together would constitute a decisive factor in the superiority of this species over Neandertal.
2) Environmental causes
Among the hypotheses that have recruited more followers so far, we find one pointing to a sudden climate change at the end of the last glacial period as the cause of Neandertal extinction (Finlayson, 2010).
However, it is possible that Homo neanderthalensis was wiped out due to simultaneous volcanic eruptions occurring 40,000 years ago in the Caucasus and Italy. The eruptions would have caused a decrease in resources affecting their diet, while Homo sapiens could have survived thanks to the presence of other groups of this species in Africa and Asia (Golovanova et al., 2010).
3) Physiological causes
There are two less popular theories but equally interesting to know. First, some researchers have suggested that the consumption of infected tissues through cannibalism was the cause of the species' extinction. These tissues would be neural, and their continuous consumption could have led to adverse effects on the body that became lethal over time (Rosas, 2010, p. 113).
Lastly, thanks to the Neanderthal Genome Project, more and more data is known about this species' DNA. In their studies, close family ties between individuals of the same group have been observed, which may have encouraged the frequent appearance of mutations that negatively affected the survival of Homo neanderthalensis (Rosas et al., 2015, p. 84 – 85).
Conclusions
The main issue with all these theories is the lack of conclusive evidence in the archaeological record. This is the case, for example, of those theories developed under the idea of competition between sapiens and Neandertals, as their coexistence in the same space has not been well reflected yet, and even if it were so, this would not necessarily imply a competition. It is equally difficult to determine the actual impact that environmental variables had on these societies, and the same applies to theories related to physiological reasons.
Having made this brief overview, we could conclude that probably the causes of Neandertal extinction are multiple, although it is still not possible to define the level of involvement of each one. What is clear is that the paradigm has undergone a significant change since the beginning of studies on this species, opening up to new proposals that finally leave behind the stereotypical image of a brutish and unintelligent species.
Bibliography
Burton, C. M., Riel-Salvatore, J., Anderies, J. M., & Popescu, G. (2011). Modeling human ecodynamics and biocultural interactions in the late Pleistocene of western Eurasia. Human Ecology, 39(6), 705-725.
Finlayson, C. (2010). The Neanderthal Enigma. Critica.
Golovanova, L. V., Doronichev, V. B., Cleghorn, N. E., Koulkova, M. A., Sapelko, T. V., & Shackley, M. S. (2010). Significance of ecological factors in the Middle to Upper Paleolithic transition. Current Anthropology, 51(5), 655-691.
Houldcroft, C. J., & Underdown, S. J. (2016). Neanderthal genomics suggests a Pleistocene time frame for the first epidemiologic transition. American journal of physical anthropology, 160(3), 379-388.
Mellars, P., & French, J. C. (2011). Tenfold population increase in western Europe at the Neandertal-to-modern human transition. Science, 333(6042), 623-627.
Rosas, A. (2010). The Neanderthals. Centro Superior de Investigaciones Científicas.
Rosas, A., Estalrrich, A., García-Tabernero, A., Huguet, R., Lalueza-Fox, C., Ríos, L., & Rasilla, M. D. L. (2015). Paleoanthropological research on the Neanderthal fossils from El Sidrón (Asturias, Spain). Cuaternario y Geomorfología, 29(3-4), 77-94.
Shipman, P. (2015). The Invaders: How Humans and Their Dogs Drove Neanderthals to Extinction. Harvard University Press.
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