As defined in ecology, an invasive alien species is one that has been transported by the human hand beyond its native region, crossing barriers that it could not cross naturally – this is what we call exotic ecology -. Later, this species has been released into new ecosystems, where it successfully survives and reproduces , and after forming stable populations —what we call naturalization— , it quickly and massively disperses beyond where it has been introduced , frequently generating negative impacts. wherever it is installed. We call this invasion . When talking about invasive species, some examples automatically come to mind: the American mink, the red crayfish, the pike, the Florida slider, the eucalyptus … but the question often arises: Is it the human being? an invasive alien species?
When we talk about invasions referring to the human species, Christopher Columbus, Genghis Khan or Napoleon are invoked by our memory. But in this case we are referring to the ecological aspect of biological invasions , and we leave aside other definitions of the term invasion, warlike, economic or sociopolitical. Referring to this ecological definition of invasion, some ecologists reach the most visceral misanthropy, and affirm emphatically that yes, without going into nuances or possible exceptions. There are also people who categorically deny this idea, as do many others. But, regardless of ideologies, the question of whether or not the human being is an invasive species can be answered from the study of our own ecology and natural history , as we could do with the raccoon or the water hyacinth.
No species is invasive everywhere, nor is it always . Biological invasions are events that are framed in a specific place and time. A human population residing in sub-Saharan Africa, with a way of life linked to natural environments, such as the Himba, the Surma or the Maasai , cannot be said to be exotic in ecological terms, much less invasive. In fact, for the first tens of millennia of our existence as a species, we never made it out of Africa.
Any human population residing outside the African continent, the native region of humanity, would therefore be an exotic population in the ecological sense. After all, the first species that humans transported out of their natural habitat was humans themselves . However, being exotic does not make them invasive. For several millennia more, human movements were slow and gradual, more similar to the colonization process that species carry out naturally, than to a true biological invasion, rapid and massive. Many human populations still extant today, such as the Mentawai of Indonesia or the Awá of Brazil, are ecologically exotic but not invasive .
But yes, there have been invasive human populations. The ability to transport large numbers of people in a short time through great barriers such as mountain ranges, seas or oceans, to settle and conquer new lands in a few decades is something that has been accentuated in recent centuries, and recently in a much more massive. The human being has invaded large extensions of territory and has extinguished a large number of species . We tend to transform the ecosystems in which we settle to adapt them to our needs, generating impacts far beyond the places we occupy . Those behaviors are defining of some invasive species. And in our case, we have caused such massive damage that it has repercussions on a planetary scale.
When we find an invasive species that is causing impacts, one course of action is to try to mitigate those impacts. In general, the protocol goes through trying to control the invasive species. It is also true that, when studying invasive species, the human being is excluded from that category . Perhaps it is because of that feeling that human beings have of being above the rest of the species, as if they were an entity outside the ecosystems. Although it seems that this trend is beginning to change and there are beginning to be studies that include Homo sapiens as a variable in ecological studies .
Perhaps the human being, as an animal aware of its actions and knowing what its consequences are, should take responsibility for the impacts it causes and try to mitigate them in some way.
Perhaps we should consider as a species to stop causing more and more damage in order to accumulate benefits , which are not always necessary, and which are generally only for a few.
Perhaps we should look up , and assume that infinite economic growth is not feasible .
REFERENCIAS
Blackburn, T.M. et al. (2011) ‘A proposed unified framework for biological invasions.’, Trends in ecology & evolution, 26(7), pp. 333–9. doi:10.1016/j.tree.2011.03.023.
Dhara, C. and Singh, V. (2021) The Delusion of Infinite Economic Growth, Scientific American. Available at: https://www.scientificamerican.com/article/the-delusion-of-infinite-economic-growth/ (Accessed: 23 January 2022).
Garrido-Pérez, E.I. and Tella Ruiz, D. (2016) ‘Homo sapiens (Primates: Hominidae): an invasive species or even worse? A challenge for strengthening ecology and conservation biology. (Translated from Spanish).’, Puente Biologico, 8, pp. 43–55.
Long, A. and Tyson, R.C. (2014) ‘Integrating Homo sapiens into ecological models: Imperatives of climate change’, Ecological Complexity, 20, pp. 325–334. doi:10.1016/j.ecocom.2014.05.008.
