For most people who live in big cities (an ever-increasing proportion of the world's population) the issue of species loss seems an irrelevance.
What does it matter if one more species is irretrievably lost for ever, when I have my house and car and my job in the city? Their lack of connection with the living world, other than with other humans in their urbanised world, does not mean that they are not inextricably linked to the other species who live on this planet-- they just can't see it. Their food is bought at the supermarket in vinyl halls plastic packaged and often pre-prepared. They do not see, nor do they care, about where those former living things came from: what lives they had, how they interconnected, how they communicated, their thoughts and feelings. The food they gather at the supermarket is simply a dead product-- sublimely and most ridiculously illustrated by the little plastic stickers on the fruit we buy there--the ultimate commodification of nature.
But the reality is that all that food, animal and vegetable, arriving at the supermarket storehouse was once living, was in fact directly connected to the rest of the living world in subtle and often invisible ways to humans. That interconnection between species is the net that keeps us all alive--a net that is steadily being undone by humans through ignorance and greed.
As recent research over the past decade has noted, all species on the planet not only possess their own unique DNA, but also multiple strands (often in much larger volume) of DNA and micro-biomes from multiple other species, mainly microbes. Anything and everything, from the bacteria that inhabit our guts and allow us to digest food that would be otherwise indigestible to us, to the bacteria and microbes that come into contact with our skin and that we inhale. As Bordenstein noted in 2015: Animals and plants are no longer heralded as autonomous entities but rather as biomolecular networks composed of the host plus its associated microbes, i.e., "holobionts."--from ' Host Biology in Light of the Microbiome: Ten Principles of Holobionts and Hologenomes':)
The microbiome concept, that is, the collective communities of microorganisms, their genomes and interactions, was first used in the context of microorganisms that inhabit the human body. Since then, numerous studies have adopted this term to describe microbial communities associated with other mammals, insects, fish or plants. For humans, the microbiome significantly contributes to metabolism and provides functions that humans did not need to evolve on their own (Gill et al., 2006). Hence, the genes present in the human microbiome are considered the secondary genome". In the human microbiome, the highest density of microbes is found in the gastrointestinal tract, where 'they synthesize essential amino acids and vitamins, and process components of otherwise indigestible contributions to our diet"..- Cross-kingdom similarities in microbiome functions, Rodrigo Mendes & Jos M Raaijmakers (2015).
Thus, (the) nature-relatedness (a person's level of connectedness with the natural world ), biodiversity of ecosystems in which humans reside or to which they are exposed, access to greenspace and/or habitation in rural environments can have beneficial effects on physical and mental wellbeing ... (However the) erosion of environmental ecosystems is affecting biodiversity and microbial ecology. Together with declining nature-relatedness this is reducing human contact with immunomodulatory organisms found in natural environments reflected in differences in skin microbes. This is increasingly being recognised as a risk factor for chronic inflammatory diseases"...There is now consistent evidence that environmental degradation, whether by climate change, invasive species or industrial activity, is linked to diminished human physical and mental health [110, 111].
The very existence of this skin-environment interface raises important questions about how erosion of global biodiversity, and declining contact with the natural environments is affecting skin ecosystems and human health . Examining this question in the context of the epidemic rise of allergy and other inflammatory diseases is informative because allergy is one of the earliest manifestations of inflammation often first observed in the skin as disruptions in barrier function and atopic eczema. Furthermore, the declining microbial diversity that has been long linked to the rise in allergic disease also has important implications for other organ systems across the life course. The skin microbiome: impact of modern environments on skin ecology, barrier integrity, and systemic immune programming: Susan L. Prescott et al (2017).
Or again. It is increasingly evident that inflammation is an important determinant of cognitive function and emotional behaviors that are dysregulated in stress-related psychiatric disorders, such as anxiety and affective disorders. Inflammatory responses to physical or psychological stressors are dependent on immunoregulation, which is indicated by a balanced expansion of effector T-cell populations and regulatory T cells. This balance is in part driven by microbial signals... With the global trend toward urbanization, humans are progressively spending more time in built environments, thereby, experiencing limited exposures to these immunoregulatory "old friends." Here, we evaluate the implications of the global trend toward urbanization, and how this transition may affect human microbial exposures and human behavior.-- The Microbiome of the Built Environment and Human Behavior: Implications for Emotional Health and Well-Being in Postmodern Western Societies. Stamper CE1 et al (2016).
- All organisms are capable of genetic change in their own lifetimes through external microbiome absorption and adaptation (an adaptation of the old Lamarckian evolution theory, with a Darwinian perspective)
- The importance of being in regular physical contact with the rest of the living world has been vastly under-rated in its effect on health and mental wellbeing. An organism's health and wellbeing depends on having a wide variety of external microbiomes to incorporate into its body and genetic structures on an ongoing basis.
- Modern human society is dramatically reducing not only human's interchange with microbiomes, but also, through poisonous agribusiness practice and destruction of habitats, is irretrievably destroying all species' capacity to genetically adapt and change and to have optimum wellbeing.
- The steadily decreasing number of species in the world (largely by human ecocide) markedly increases all species' capacity for survivability.
- Human beings' obsession with creating cities, with 'clean' environments and the sealing over of the living world with concrete and tar, are rapidly reducing microbiome diversity on the planet.
- For the human species to survive for further millennia it has to acknowledge its interdependence with the rest of the living world, and stop creating dead spaces on the planet. Celebrate all life!