Utku Perktaş

Dr. Utku Perktaş is a professor of biogeography in the Biology Department at Hacettepe University.

There have been five major extinctions in the history of the Earth. The first one occurred 2.45 billion years ago: almost 70 percent of the species that existed at that time disappeared. The latest one occurred 66 million years ago; the giant dinosaurs disappeared as a result. But during these extinctions, Man was not yet on Earth. Everything was happening in its natural course of action. When human beings evolved and started to live on Earth, things began to change. The world’s biodiversity experienced a bottleneck. The climate deviated from its normal course. Microbes, diseases, and outbreaks began to manifest themselves. In the meantime, increasing human population, altering the climate accordingly, is the biggest threat to the Earth’s biodiversity. Thus, the Earth, having experienced five major extinctions in the past, is now going through the sixth extinction today. We have seen the steps towards the sixth extinction in different ways, and we continue to see them. The outbreaks we experienced in our recent history are the best examples that illustrate these steps.

 A new step towards this sixth extinction, nowadays, shook the globalizing world on a very large scale once again. The social and economic dimensions of the outbreak negatively affect people from different societies. The World Health Organization (WHO) must be aware of these steps, since its list of diseases included one which may occur around this time – it would be called “DiseaseX“. WHO, like in the previous outbreaks, seemed to point out that a new outbreak could cause trouble and a new step towards another extinction.”. WHO, like the previous outbreaks, seemed to point out that a new outbreak could cause trouble and a new step towards another extinction.
I wonder if we learned our lessons from the outbreaks we experienced in our recent history; would we be spending the quarantine days we live today much more easily? Wouldn’t we have experienced the biodiversity crisis? Would the economies be better? It looks as though we haven’t learned our lesson well enough to answer these questions, as of today; due to the new type of coronavirus, the number of cases has exceeded 200,000 worldwide and the number of deaths has reached 8,400. For this reason, I wanted to draw attention to past outbreaks by looking at our recent past; because we have a lot to learn from history…

The ebola lessons we should have taken

Ebola was reported almost 40 years ago in 1976 near the Ebola river of Congo. It was caused by the illness of the people in contact with the tropical forests. After exiting, it affected many people in Africa; deaths exceeding tens of thousands were recorded. About 20 years ago, the people of Gabon, who hunted in the tropical rain forests in January 1996, were fed with monkeys, the main sources of protein. The result was fatal, the locals began to die with high fever, diarrhea, bleeding and severe pain. Ebola, believed to have disappeared in 1976, was revived twenty years later. This time the disease killed 254 people in a short time; advances in medical treatment made the fight more effective. But Ebola is still not over, it remains a risk to Africa.
These people were, as always, connected with their natural habitat where they lived because of their nutritional needs. These people who lived close to the tropical forests of Africa always had a culture that was at peace with the forests. Forests had been to some extent a food supply for these people. The forest fed them, and they protected these forests. However, the forests obviously could not carry this burden anymore. Because people were going down to the depths of the tropical forests in order to find food and create a place to live for themselves. This deadly disease, transmitted from person to person, was like a reaction of the nature against the human being connected with natural life and irresponsibly using natural resources to feed their growing population. With increased deaths, the situation has changed for people. Now the forests have lost their attractiveness for them, forest destruction has thus accelerated. These widespread destructions that we see today have caused people to experience lethal affairs with viruses. Although the virus was identified for the first time in 1976, it has existed for more than 10,000 years.

The destruction of nature is backfiring

For nearly a decade or two, tropical forests and natural habitats full of exotic wildlife have been thought to threaten people by harboring viruses that cause new diseases in humans such as Ebola and HIV. But people are still doing their best to make unlimited use of these environments. The situation now evolves unconsciously into the irreversible destruction of places that are the source of these terrible viruses. Of course, this increased destruction certainly causes the climate change. This situation provides a positive feedback for these fatal diseases. In other words, the probability of occurrence of diseases increases and diseases spread to broad geographies on Earth. A study published in the Nature Communications announced that the climate crisis will expand the distribution of Ebola and will rapidly increase the risk of areas previously unaffected by the virus. The study showed that the climate crisis would increase the spread of the deadly virus from animals to humans by 1.75 to 3.2 times by 2070.
Increasing world population means a rise in nutritional and sheltering needs; this means that human and wildlife interactions are much higher than expected, and therefore this means the loss of biodiversity. Increasing world population means an increase in nutritional and sheltering needs; this means that human and wildlife interactions are much higher than expected, and therefore loss of biodiversity. Ebola has been one of the most important examples of how the pressures on biodiversity can have devastating effects on people. That’s why I define Ebola as a step towards the sixth extinction. Contact with living creatures in areas with the highest biodiversity in the Earth, such as tropical rain forests, is essentially related to microorganisms, pathogens that we never know or see. The cost of this relationship should not be underestimated due to the deaths we have seen so far. But have we learned enough lessons from this example? When we consider these days we passed through, my answer is “NO”. There is no doubt we are not talking about Ebola today. We are talking about a completely different pandemic disease with high mortality rates. But the reason is again a virus with natural origin, nCoV-2019. So, a new step towards the sixth extinction…

Increasing threats

When the most important topic of these days is coronavirus, I was interested in David Quammen’s book “Spillover: Animal Infections and the Next Human Pandemic”. Quammen wrote, “We are rapidly invading tropical forests and natural geographies that house many animal and plant species, and the creatures living in these geographies host many unknown viruses”. And then he continued, “We cut down the trees; we kill or cage animals and ship them to the markets, we trade animals. We disrupt ecosystems and separate viruses from their natural hosts. But viruses have to need a new host. We are usually those hosts ”. The United States Center for Disease Control and Prevention estimates that three quarters of the diseases that infect people today are from animals. Examples like Ebola may increase when we examine our recent history. SARS, for example, is a viral disease from the coronavirus family that killed more than 700 people in 30 countries in 2002 and 2003. Other disease viruses, such as the Zika and West Nile virus, which appeared in Africa, have also mutated and spread to other continents and pose a serious threat to public health. The common feature of these viruses is that they originate from living things in nature that we rarely contact.
The invoices for the pressures on biodiversity are increasing threats to human health. The fact that animal-borne diseases that we see today are related to environmental changes due to human behavior is also shown in different studies. Depending on these results, it is said that the transmission of diseases from wildlife to humans is “a hidden cost of the economic development of societies”. We are blinded by economic development and create habitats where viruses can be easily transmitted. Then we spread viruses to the world with our own hands. Viruses without borders are beginning to serve as a source of threats in many areas. For this reason, the world’s leading biodiversity specialists underline that it is a very important danger for global health, global security and global economy due to the extraordinary properties of pathogens that cause animal-borne infections. Nature can threaten human health in terms of what they have, but what we have to keep in mind is that the real threat comes after the human affect on nature. The coronavirus, COVID-19 or nCoV-2019, is the most current example of this situation.