We Live in a Hyperconnected World
We live in a hyperconnected and fragile world. A world that allowed us to come together from all corners of the globe at the World Biodiversity Forum, organized by the University of Zurich Research Priority Programme ‘Global Change and Biodiversity’ and the international research network bioDISCOVERY, held in early February 2020. The meeting, described as eclectic, set out to explore the driving factors behind the biodiversity crisis, and to forge a path forward to safeguard all life on earth. We shared knowledge of the many different ways in which humans impact biodiversity. We discussed transformations required to reduce these impacts. We talked of how the conservation and protection of biodiversity could be brought to the forefront of decision-making. The participants left the meeting inspired, enthusiastic and energized to tackle the manifold challenges that lay ahead.
It is also possible, despite adherence to all precautions advised at the time, that some of the participants shared something else, and by doing so left with a little more biodiversity than they arrived with. And little did most know how much the world would change over the next few months, with our impacts on biodiversity as well as the hyperconnectedness of societies conspiring against us.
Biodiversity loss is now recognized as a major global risk for societal and human wellbeing in reports by the World Economic Forum and Future Earth. Both reports also include infectious diseases among the top ten risks, but with a low likelihood of occurrence. A few months later, societies across the globe are dealing with COVID-19, a disease caused by the virus SARS-CoV-2. This is a previously unknown virus and disease, but as the name suggests, is a coronavirus closely related to SARS, which broke-out in 2003. This new-to-us virus, like two-thirds of pathogens that infect humans (viruses, bacteria, fungi and parasites) is zoonotic: of animal (non-Human) origin. It is very likely that there are many of more of such pathogens “out there”.
NOT KNOWING WHAT IS “OUT THERE”
A large proportion of biodiversity to date is unknown – and estimated 86% of species on land, and over 90% of marine species. New species are brought to light with every expedition, every survey (see here for some newly described species in 2019), but most “unknowns” are among the inconspicuous and small organisms that nevertheless have pivotal functions in ecosystems. For example, small arthropods and microbes that are important for nutrient cycling in soils. Some of these unknown species might even occur in our back yard. Many of these species are harmless for humans, but others, such as the corona virus, can have considerable impacts on our health and wellbeing – including wide-ranging consequences for society. But pathogens do not have to impact human health directly to have wide-ranging consequences for human well-being. For example, the spread of a single strain of potato blight to Europe in the mid-1800s not only caused the Great Irish Famine, but also contributed to unrests and revolutions across Europe.
Having knowledge of “what is out there” – in particular microbial and viral diversity – gaining knowledge where species occur, and understanding their functions in various ecosystems as well as the way they may (negatively or positively) impact human wellbeing, is crucial to preventing surprises, e.g. outbreaks of diseases. This requires much more extensive and intensive sampling of biodiversity than is currently performed, including microbiomes of wild plants and animals.
The cost of extensive and intensive biodiversity assessment – a 5-year inventory across different taxa in Ugandan forest reserves (3 000 km2) cost US$ 1 million, but also see here for cost-benefit analyses of biodiversity surveys in tropical forests – are dwarfed by the economic costs of the SARS-CoV-2 outbreak. The GEO Biodiversity Observation Network (GEO BON) aims to improve biodiversity observation across different scales and levels of organisation to aid decision making.
HUMAN AND ENVIRONMENTAL HEALTH ARE CONNECTED
The current pandemic is a symptom of how humans have changed the earth system; and illustrates the role of ecological and social drivers in disease transmission. Human impacts on the environment increase the likelihood of humans coming contact with pathogens that are “stored” in the wild. Changes in climate and loss of biodiversity make the emergence of diseases and disease outbreaks more likely. With increasing temperatures, species distributions change – bringing pathogens to new regions. Changes in temperatures also affect survival rates of disease vectors and pathogens. Many, like plant rust, are usually suppressed in cold winters, milder winters lead to an earlier outbreak of the disease. Others, often viruses such as the common cold or flu, spread more readily in colder temperatures, and are suppressed during hotter periods.
Habitat transformation and the resulting loss of biodiversity, for example a change in predator-prey relationships and host occurrence can also lead to a disease outbreak. A prime example for this is the increase in Lyme disease in the north-east of the US, where white-footed mice thrive in the fragmented forests, but their predators do not do as well.
Transformation and fragmentation of natural habitats, as well as the hunt for bushmeat and exploitation of other (forest) resources also increase the likelihood of humans coming in contact with pathogens. Ebola has been linked to deforestation in the Congo Basin, with transmissions occurring through contact with infected bushmeat (mainly primates or rodents). Other viruses are transferred through the faeces or saliva of infected animals.
Humans are not the only ones to contract zoonotic diseases, these are also transmitted to domestic animals. Avian influenza, for example, is transferred from wild birds to poultry, and then quickly spreads through bird farms. The disease spreads across continents by human trade rather than bird migration. The extreme connectedness of our world also facilitated the rapid spread of COVID-19 across the globe. We now “need to contain the processes that drive pandemics, not just the disease”.
PROTECTING NATURE, PROTECTING HUMAN WELLBEING
Land use change, climate change, wildlife trade, intensive livestock production as well as antimicrobial resistance all contribute to increased emergence of zoonotic diseases. The Global Heath Security Index aims to measure the readiness of a country to manage events such as a pandemic. One element of the Index is Prevention. This element should include activities such as protection of natural habitats, for example, preventing domestic (animal) species from mixing with wild species, thus reducing potential disease transmission; nature-based solutions, such as the restoration of forests, not only contribute to the mitigation of climate change, but can provide a number of social and environmental benefits; restoration of wetlands and riparian zones can reduce the risk of exposure to waterborne infectious diseases.
In our hyperconnected world, we move one lever and many cogs turn, often in different and unexpected directions. The prevention of future outbreaks requires solutions that create synergies across health, biodiversity climate policy, as championed by the OneHealth approach, which sees human, animal and ecosystem health as interrelated. International collaborations across disciplines, between science and management are required to address the socio-ecological drivers of emerging diseases, and to find international solutions. To this effect, the Health Knowledge Action Network of Future Earth proposes a system-based approach to prevent future pandemics. Gatherings such as the World Biodiversity Forum 2020, can spark the collaborations necessary to address the challenges of today’s human-influenced planet.
Co-written by Owen Petchey, Full Professor, Department of Evolutionary Biology and Environmental Studies, University of Zurich, Switzerland and Dr. Cornelia Krug, Science-Policy Liaison, URPP Global Change and Biodiversity, Department of Geography, University of Zurich, Switzerland.
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